Sunday, April 18, 2021

#510 - Saturday, April 17, 2021 - New Off-Axis Guide Cam!

On long-focal-length telescopes like Schmidt-Cassegrains (and especially Schmidt-Cassegrains, with their floppy mirrors), off-axis guiding can provide better guiding than a guide scope.  I've been using an off-axis guider with my C8 since 2018, and despite some troubles, it has still largely been a better solution than when I was using a guide scope.

I initially paired it with my QHY5 (the original red puck), but found it to be not sensitive enough to pick up guide stars, even at f/6.3 (1280mm).  I picked up the more-sensitive QHY5L-II CMOS guide camera not long after, which typically gets just barely enough signal-to-noise ratio to hold onto a guide star on my setup.  Of course, it performs better under dark skies, but any drop in transparency, and I'm barely holding onto a star, especially in the spring when the density of stars around out-of-galactic-plane targets tends to be a lot lower.

A good night of guiding in February...just enough SNR to hold onto the star.

While the QHY5L-II worked more often than not for me, I started growing tired of losing images because of lost guide stars, and losing hours of the night while Sequence Generator Pro made attempts to recover.  So I've been kicking around the idea of getting a Lodestar, which is a tiny CCD camera made by Starlight Xpress with big juicy pixels and high sensitivity.  The current iteration of this camera is the Lodestar Pro, which was 8.6 micron pixels and 77% quantum efficiency.  Unfortunately, it costs almost $600, which is a bit hard for me to justify when my system mostly works. 

However, I recently came across a used original-model Lodestar being sold by an area astronomy club member, so I pounced on it (along with an enormous 315mm electroluminescent flat panel and a network-enabled sky-quality meter).  The older version of the Lodestar has 8.4 micron pixels and 65% quantum efficiency, so not a huge difference technically (several other specs are the same as well), although the read noise is lower in the new version.  

The first thing to do was to make sure it would talk to my laptop.  I installed the ASCOM driver for it, connected it to SharpCap, and it started taking frames right away.  Woot!  Shining light on it showed a response.

Focusing the Guide Camera

The next challenge was getting it on the off-axis guider.  This is an event.  Getting it focused is not easy.  You have the three-fold problem of not being in focus, not having a star in the field bright enough to show up when very unfocused, and it's very hard to tell where the OAG is looking to get a star placed in it.

The first night I tried it, Wednesday, didn't go well at all.  There were low clouds running across the sky, and once I got a bright star in my main camera and started slewing around to see if it would show up as a big unfocused blob in the guide camera, a cloud would inevitably cover the star.  I gave up that night and went to bed.

Saturday night was much better, and had better transparency.  Bonus points, the waxing crescent Moon was high enough above my lemon tree to see with my C8.  A super-bright object is a lot easier to land in the guide camera because you can see it coming from off the edge.  I slewed the scope over to the Moon, centered and synced it in the main camera, and then slewed above and below the main camera image to see where it would show up in my guide camera.  Pretty quickly I could start to see the guide camera image lighting up, so I adjusted the exposure time down for seeing the Moon's surface, and got the guide camera roughly focused.  I also created a field-of-view indicator element in TheSkyX where the Moon was in my guide camera compared to the main camera so that I could more easily land a star inside of it.

The center rectangle is the main camera; the smaller one above is my old guide camera; the rectangles above and below are the E and W side of the pier positions of the guide camera, respectively.

Next, I slewed the main camera to Regulus and centered it, synced the mount to it (so that it would be in the correct position with respect to my camera FOVs on the map), and then slewed the mount so that Regulus would show up inside the guide camera box.  And bang, there it was!  Now time to critically-focus.

Now, I use two different brands of filters: Astronomik CLS-CCD & RGB, and Chroma narrowband filters.  They have different thicknesses, and thus adjust the main camera's exact focus point a bit.  ("A bit" on my PrimaLuce Esatto focuser is still like 20,000 steps).  So to set the guide camera position so that it's mostly in focus for both focus points of the two sets of filters, I take the CLS-CCD filter's in-focus point and the H-alpha filter's focus point and split the difference.  I set the focuser there in the middle of the two, and then moved the camera in and out until the star was as small as it would get.  Now, since we're so far off-axis and this is a Schmidt-Cassegrain, the star shapes are pretttttyyyy yucky, so "in focus" is hard to determine.  But I got it about as small as it would appear in the camera, and called it good.  

Unfortunately, that focus point has the Lodestar just barely inside the tube!  I put on a C-mount extension tube, but it has a lip on it that won't let me insert it far enough to get the camera in focus.  So I need to hunt down an extension tube that doesn't have a lip.  We'll see if I can find one.  

Left to right: ZWO ASI1600MM Pro, ZWO electronic filter wheel, 21mm spacer, Lumicon off-axis guider + Lodestar, PrimaLuce Lab Esatto focuser

Time to Test

Next, I needed to re-calibrate guiding in PHD2 for the new camera.  I slewed the scope to somewhere roughly due East and about 50 degrees up the sky and started looping 8s exposures.  Now, I had already discovered during initial connection testing that this Lodestar has a lot of hot pixels.  And because of the way the camera is read out, some kind of interlacing to increase the speed, the hot pixels really look rather star-like.  I did try to take a dark library in PHD, but they never work for me -- they always over-subtract, and I end up with a bright gray image with black specs where the noise pixels used to be.  However, this is one place where the gross shape of the stars off-axis in a Schmidt-Cassegrain actually works out in my favor: they're way bigger than the hot pixels.  After some trial and error, I set the HFD (half-flux diameter) minimum value in the settings (brain icon) to be 3 pixels, and this did the trick.  PHD grabbed what appeared to be dim, blobby stars rather than the star-like noise pixels.  

The hot pixels really mess with PHD's auto-stretching algorithm, so I could barely even see the guide star.  However, your ability to see it isn't what matters -- only PHD's ability to see it.  This is given by the SNR (signal-to-noise ratio) reading.  The higher the value, the better (until it says "SAT" which means you're saturated, which diminishes PHD's ability to calculate the centroid of the star).  While I have been used to values between 5-20 on the QHY5L-II, the Lodestar showed values of 50-90, even in star-poor galaxy regions!

This was very exciting and very promising indeed.  So I got the main camera cooled and started running the sequence for the C8 for that night, which consisted of planetary nebula Abell 31, planetary nebula Sh2-313 (Abell 35), galaxy NGC 5248, and M16 Eagle Nebula.  Abell 31 had some initial trouble with the guide star wandering off, but it was almost behind the tree anyway, so I had SGP just advance to the next target.  Despite Sh2-313 being really low in the south for me, the PHD2 screenshot above was taken there, showing good SNR even through muddy and light-polluted skies.

The rest of the night was quite successful -- all of my targets ran and got a lot of subframes, and it looks like the night finished strong with M16, which is in an area with plentiful bright stars to choose from.

0.55 arcsec RMS guiding is pretttty good :D  And so is that SNR and star profile!

Single luminance (CLS-CCD) subframe, 300s, M16 Eagle Nebula, on the C8

Monday, March 8, 2021

How I Organize My Data

Astrophotography generates a lot of data -- what is one to do?  Between different cameras, telescopes, targets, months, how do you keep track?  I've only been doing this hobby for 5-1/2 years, and I already have over 12 TB of data!

Everyone develops their own organization scheme, but I have one that I think is particularly excellent that I'd like to share.  Maybe some parts of it will help you!

First and foremost -- keep a log book!

A logbook is an essential part of any scientist's toolkit.  Take Adam Savage's advice on it: 

Whether it's hand-written in a journal or notebook or typed up on a computer, it's important to keep track of some of the basics of every night you observe.  What gear you used, weather conditions, things that went well, things that broke, etc.  To make life easier for myself, I take notes in Google Keep's sticky-note-esque app (available both on smartphones and on any web browser), and then later dump all those notes into a Word document with more details.  I number every night in sequential order, and I've been keeping notes since my very first night of observing!  

Example note in Google Keep

I have semi-permanent setups in my backyard, so my equipment configurations don't change that often, but if yours do, then make sure to write down the gear you used.

Image Organization: In the Morning

Every morning, I bring my data acquisition laptops (DAQs) inside (I don't have a permanent computer housing built yet) and pull all of the images off of them onto a flash drive, and then over to my desktop computer.  I highly recommend copying the data off your laptop rather than cutting it; leave it on your laptop until you are sure it is safely transferred to your image processing computer.  Sometimes storage drives can have weird faults that wipe all your data, or data can be corrupted.  I check all my image files before deleting them from my DAQs.

On my "Stacks" hard drive (an 8 TB drive dedicated to deep sky images), I have a folder called "Backyard - To Process."  Within that folder are sub-folders for all of the targets on which I am currently taking data or haven't yet attempted to process.  One folder at the top is called "_to sort" (the underscore keeps it at the very top of the list).  When I copy the images off my DAQs, they go into a folder of the night's date.

The older folders have planetary & lunar data I haven't had time to deal with!

After scanning through all of last night's images using the Blink tool in PixInsight (or if you have DSLR images, you can just open them using Windows Photo Viewer or whatever other image viewer), I shuffle them out to their target folders in the "Backyard - To Process" directory.

The green tick marks are made by right-clicking the folder, clicking Properties, going to the Customize tab, and selecting "Change Icon."  It's an easy way to spot which datasets I have deemed ready to process.

Inside each of those target folders is another set of folders: lights, cal, finals, and PixInsight.  The light frames go into the "lights" folder (separated further by filter, if needed); corresponding master darks and flats go into the "cal" folder (copied over from my dark and flat libraries -- more on that in a minute); "PixInsight" is the folder in which I do my processing; and "finals" is where I keep final copies of the images.

Since I use this template for every dataset, I finally wrote myself a simple batch script to generate these folders and a copy of my metadata text file template (more on that in a bit).  They're very simple to make: create a new text file (right-click an empty place in the folder window, New->Text Document, and name it "something.bat" (no quotes).  Open it with your preferred text editor (right-click, Open With-> choose text editing program).  Mine looks like this:
mkdir lights
mkdir cal
mkdir finals
mkdir PixInsight
mkdir PixInsight\processes

copy "Q:\_Stacks\stats format.txt" finals
ren "finals\stats format.txt" stats.txt

"mkdir" means "create directory;" "copy" means, well, copy (first argument is "copy from" location, second argument is "copy to" location); and "ren" means "rename" (first argument is the file location and name that you want to rename, the second is what you want to rename it to).  

To execute the batch file, copy it into the folder you want to make the folders in and double-click it.  It will run quickly, and then you can delete the copy of the batch file.  If you want to get even fancier and move all existing images into the "lights" folder, you can add:

move *.fit lights

where the * means "all files with" and the .fit is the image extension my images files are saved as.

Don't forget, if you have a directory or filename that has spaces in its name, you need to put the whole filepath in quotes (like I did in the "copy" line above). 

Linux and Mac have different commands, but a similar idea.  (If you use Linux, I hope you already know how to do this!)

Image Organization: Each Dataset

First, I have a different hard drive for each type of data: deep sky, planetary, timelapse, and miscellaneous (this has nightscapes, images collected for competitions, solar/lunar eclipses,  other people's data that I've helped them process, pictures of my telescope setups, and whatever else doesn't have a home).  Having different hard drives is just a result of having too much data to fit on a single drive, so I broke it up my logical categories.

In general, I organize my data in this hierarchy: target, attempt.  Inside each attempt is the same setup as in "Backyard - To Process," with the cal, lights, finals, and PixInsight folders.

An "attempt" on a target can be one night, or many nights, but it's all the data I am going to combine into a single, final image.  Occasionally, I go back and combine multiple datasets; those combinations would go into the most recent attempt folder that is included in that combination.  For example, if I combine data from Lagoon #4 and Lagoon #5, the processing steps and final images would go into the Lagoon #5 folder.

Metadata File

Even if you are young with a more keen mind, once you get enough datasets rolling, it becomes easy to forget which gear you used, where you took the images, etc.  The best way to combat that is to write it down and keep it with that dataset.  In the "finals" folder, I make a simple text file called "stats.txt" that holds all that info in a standardized template I developed.  Text files are nice because they are readable on every platform, for free, and will be for a very long time.  My preferred app is Notepad++, but you can even just use the simple Notepad app that's built into Windows, or vim on Linux if you really hate yourself, or whatever text editor you prefer.

In addition to having a text file with each dataset, I also have a summary of all of these text files for easy searching in an Excel spreadsheet.  It's sortable and filterable, so I can quickly do things like find which target attempt uses compatible gear to combine datasets; find example images for creating comparisons between telescopes, cameras, techniques, etc; see when the last time I imaged a target was; see if I need to re-do a target now that I have better skills; all sorts of things.  It's also handy for when I'm at a star party or outreach event and someone asks, "How long was this exposure?" or "What telescope/camera did you use?" and I can quickly go look it up from my phone.

Green highlight means "re-process with more skill;" yellow highlight means "need more data."

Processing Files

Inside the "PixInsight" folder in the attempt folder, I have more folders that contain my processing steps.  I number them sequentially so that it's easier to go back and re-do steps if I don't like the result.

In addition, I keep notes in the metadata file with what processing steps I used and some details about them as needed (what type of pixel rejection I used in stacking, how many iterations of deconvolution I did, which subframe I used as the reference frame for registration, etc).  

Deleting Data

I never delete entire datasets, even if they seem like crap.  For one, they might actually be fine, but I don't have the skill to process them yet.  Or, if they truly are crap, they make useful teaching examples about how to spot clouds and bad tracing, or can even help diagnose problems with your gear, like frost spots or burrs on a gear.  (I do delete bad subframes in a single dataset, although sometimes I set them aside for further analysis or using as examples).  It's also fun to go back and see how bad my images used to be and how far I've come :)

To keep dataset size down, once I'm done processing, I delete all of the pre-processing data: calibrated, approved (from SubframeSelector), debayered, and registered subframes.  But I keep the original stacked data to start re-processing from (I don't often have to go back and re-stack data after I've given it a few attempts), and I keep the matching calibration files (master darks and flats) with the dataset so I can easily re-generate the pre-processing frames if needed later on.  This saves enormously on dataset size, especially now that I gather 20-30 hours of total exposure time per target these days.

File Naming Convention


I use Sequence Generator Pro to do my data acquisition, and you can program the file naming convention right in the sequencer.  They've even got a little button with what all of the reference key symbols mean, and there are a ton of bits of information you can include in the filename.  My personal preference is a filename like "," which has the important pieces of information that change from image to image for my setup: target name, exposure time, camera temperature, filter name, and then the frame number.  (I always use the same gain, offset, and binning, and I don't yet have a rotator to need the angle).  I also like to have the images for a given target be stored in a folder of that target name.  So my filename convention in SGP is this: "%tn\%tn_%el_%ct_%fe_f%04."

Other metadata, such as RA/dec, gain value, and any other SGP knows because I've programmed it into the Equipment Profile (such as pixel scale, focal length, and more) are saved in the FITS header (which can be accessed in programs like PixInsight, FitsLiberator, and more).  

Final Images

After I'm all done processing an image, it's time to save it out, in a couple of formats: XISF (PixInsight's preferred format), TIFF (for high-quality digital copies and for printing), and JPG (for posting on social media and keeping a copy of on my phone).  

The filename I give my finals files leads me straight back to where their original data are stored.  For example, Orion Nebula #17's final is named orion_15_1_5.  The convention goes: target-name_attempt_stack_process.  Each new attempt at imaging a target increments the attempt number.  Each different time I stack it (whether that's in different software, using different stacking settings, or mixing with other data) increments the stack number.  And each post-process (applying different techniques post-stacking) increments the process number.  So orion_15_1_5.jpg is the Orion Nebula, attempt #15, stack #1, process #5.

This way, when I have just the jpg on my phone, I can immediately know where to go looking for the image acquisition details (like exposure time, camera, telescope, location, etc) either in the metadata file or the Excel spreadsheet.  (This has saved me after AstroBin's massive data loss event -- I name my images on there with their attempt numbers, like 'M42 Orion Nebula #15,' so it was easy to figure out which file I needed to re-upload!)

Calibration Libraries

News flash: You don't have to take new darks and flats every night you image.  You can generate libraries of files that you can re-use, depending on the circumstances.


With cooled cameras, it's relatively easy to generate dark libraries, since you can set the camera temperature (to within what your camera can cool to depending on ambient temperature).  To build my dark library, I would set my camera out on the back porch, cover it a bin and blanket for greater darkness, run the power and USB cables inside, and then use SGP to run an all-night sequence of various exposure times at my selected temperature and gain.  I've even taken darks in my refrigerator when I needed a set I didn't have and it wasn't cold enough outside to match some recently-acquired data!

For darks, you only need new master darks under the following circumstances:
  • Different camera temperature
  • Different gain/offset
  • Different binning
  • Different exposure time
  • Different camera (even if it's the same model)
  • Periodically, as the electronics and sensor characteristics can change over time (my darks from three years ago no longer match darks I've taken more recently, so I'm having to re-do them, on my ZWO ASI1600MM Pro)
In my "Dark Archives" folder on my Stacks drive, I have my dark subframes and master darks organized by camera, then by temperature, then by gain, then by exposure time.  (If I binned, which I do for my CCD camera but not for my CMOS cameras, there would also be a 1x1 or 2x2 set of folders).  Inside of each bottom-level folder (exposure time) is the master dark, as well as the subframes (so I can re-stack if needed).

Thanks to all my effort upfront to built up my darks library, I haven't had to take new darks on my ZWO ASI1600MM Pro in over a year.  


Flats are a little more complicated -- at least, if you have a non-permanent setup.  Flats need to be re-taken under the following circumstances:
  • Different gain
  • Different filter
  • Different telescope, reducer, or other optic-train component (even non-optics components can change your flat -- like additional vignetting from a new filter wheel, adapter, or off-axis guider)
  • Different camera (even if it's the same model)
  • Every time you either rotate your camera or remove it from the telescope
The main things that flats address are vignetting and dust bunnies.  If you rotate your camera at all, you need a different set of flats because a) the dust bunnies will be in different places (unless they're on your camera sensor or window itself, of course) and b) the location of the vignetting may change since the camera is unlikely to be smack in the middle of your image circle, and because most sensors are rectangular.  

To deal with this, I organize my flats in the following hierarchy: first by camera, then by optics train (for example, "C8, focal reducer, Esatto focuser, ZWO EFW), then by date, then by filter.  

Unless your telescope is in a laboratory-grade clean room, then yes, you will need new flats every time you set up and tear down and for each different filter.  And to capture the dust bunnies, you'll need to be in focus -- so I always take my flats the next morning, after I've focused on the stars during the night.

Backups, Backups,  Backups!!

Image if your astrophotography data hard drive failed tomorrow.  How devastating would that be?  Years of data and many, many hours of hard work, gone.  Backing up your data is vitally important.  

Local Backup

For local backup, I have several external hard drives that I backup using some free software (FreeFileSync for me, but there are plenty out there) about once a month.  Each external hard drive goes with one of my internal hard drives.  They're also handy to bring to star parties for on-site processing when I only have my laptop.  The rest of the time, they live in a fireproof, waterproof safe to help ensure their survival in case of fire.  It's also important that they're not plugged in continuously so that they're protected from power surges and lightning strikes.  

I'm eventually going to set up a NAS, aka a set of hard drives in some external hardware that uses a raid array configuration to mirror data to other drives to keep it safe from hard drive failure.  All hard drives eventually fail, especially spinning-disk drives, which typically only have a lifespan of 3-5 years.

Online Backup

Local backup is still problematic; you can't keep a NAS in a fireproof safe, and you might forget to unplug your machine or NAS during a lightning storm (especially if they're frequent where you live!).  Online backup allows you to store a backup copy of your data offsite somewhere, usually distributed across many servers around the country or world.  They have better data reliability than managing a NAS or external hard drives yourself, and your data is safe if your computer or house is destroyed.  

These services come at a cost, depending on which service you go with and what type of service.  Some services allow free backup, but it costs to download your data; this is known as catastrophic backup.  Some services have different pricing tiers for the amount of data you can store and the maximum file size.  

I personally use Backblaze.  It's $6/month for unlimited file storage, and it will backup continuously if you set it to.  If you lose your data, you can either re-download it (which will take a long time if you have a lot of it, like I do) or pay to have them ship you a drive -- currently $189 for up to 8 TB (but they'll refund you if you ship it back within 30 days). 

The only issue with online backup I've run into so far is butting up against data caps.  Comcast has a data cap of 1.2 TB in most states right now (up from the usual 1 TB due to the pandemic...woo-hoo), which means I can only upload about 800 GB per month because I use about 400 GB in my daily life (video calls, Netflix, YouTube, etc).  You do get one courtesy month where they won't charge you extra ($10/50GB I think), and in that month I did manage to get about 4 TB uploaded, but with 12 TB of astro data + 1-2 TB or something of personal data and images, it's taking a long time to get backed up. I've been working on it since October (it's now March), and I have to keep an eye on my data usage and stop the backup once I get over 800 GB.  It's a pain, but once the initial upload is complete, I should be easily able to stay under the data cap -- I probably only generate about 100 GB a month or so, depending on how much processing I do, whether I do timelapses, or whether I've been to a star party.  :)

Back it up!

It's worth your while to pursue both options.  Imagine your life without your hard-won astro data!


Dealing with so much data can be a challenge, but I totally love the system I've developed and it works great for me.  I know pretty much exactly where to find everything, in short order, and I know everything about how I created that final image.  Put some thought into how you want to organize your data and try it out.  A little planning ahead can go a long way.  I'm eventually going to write more scripts to do more automation for me (like grabbing the matching master flats and darks for my datasets!).  

Best of luck!

Tuesday, December 22, 2020

#457 - Monday, December 21, 2020 - Conjunction Junction

 It was one of the most-talked-about astronomical events of the year -- the Great Conjunction of Jupiter and Saturn!  The two heavenly bodies appear close to each other from our perspective about every 20 years, but are not usually close enough to be a big deal.  The last time, in May 2000, they were 68.9 acrmins apart, or a bit more than two full Moons side-by-side.  This year, however, they would draw as near as 6 arcminutes apart -- nearly on top of each other.  The last time they were this close was back in 1623, in the days of Galileo; however, the two planets were close to the Sun, so it is likely that nobody witnessed it.  Before that, there was the Great Conjunction of 1226, in the time of Genghis Khan, which was visible at night.  Luckily for us young folk, the next close pass of Jupiter and Saturn will occur in only 2080, which some of us may live to see.  (For more info, see this article in Scientific American).

I had put the event on my calendar some time ago, probably back in 2019, and set reminders for myself so I could prep.  Of course, with all the chatter on the Internet, how could I forget?  I started working up a plan back in the fall, and in the days leading up to closest approach, I did some test runs.

About a week before the actual night of closest approach, I saw on SkySafari that the two planets were close enough to catch in my refractor, and since it's positioned in such a way that I could see the two shortly after sunset before they disappeared behind the tree, I nabbed a video on my one-shot color ZWO ASI294MC Pro camera and produced an image.

Date: 15 December 2020
UTC: 16 December 2020 01:34
Location: East Bay area backyard, CA
Object: Jupiter & Saturn, near conjunction
Camera: ZWO ASI1294MC Pro
Telescope: Takahashi FSQ-106N
Accessories: ZWO EAF focuser, Astronomik CLS-CCD 1.25-inch filter
Mount: iOptron CEM40
Exposure: 15ms (Jupiter), 150ms (Saturn)
ISO/Gain: 120
Acquisition method: SharpCap Pro
Stacking program: PIPP
Processing program: Photoshop CC 2021

I couldn't get AutoStakkert to align the frames because of the two separated targets, so I just had PIPP (Planetary Image Pre-Processor) sort them by goodness and I pulled the best frame from each of the two videos (one for Jupiter and one for Saturn, because of the two different exposure times needed) and combined them in Photoshop.  So it's a little blurry, but still cool to see them so close!


Because they were only going to be six arcminutes apart, I was going to be able to throw a lot of magnification at them and get a nice shot.  I decided to use my Celestron 8-inch Schmidt-Cassegrain, which has excellent performance on planets.  It currently is seated on my Paramount MyT, and I've been using it for deep-sky imaging all year.  Unfortunately, the Paramount was on the wrong side of my backyard to be able to see the conjunction, which was low in the western sky -- my enormous lemon tree blocks the view.  So I went old-school and pulled my Celestron NexStar SE alt-az mount out of the garage, which I primarily use for outreach (back when we could do that in-person) and for planetary imaging that I can't reach from my backyard.  The nice thing with using an alt-az mount for this transient events is that I don't have to polar align it or even have a decent alignment model -- I can just plop it down, point it at a planet, and say "track this," and it does a decent-enough job for the short exposures of planetary imaging.  

For the camera, I decided to use my monochrome CMOS camera, my ZWO ASI1600MM Pro.  I always get better results on it, and I can get higher-resolution images from it because a) the pixels are smaller and b) every pixel is used instead of interpolating 2x2 quads of pixels to produce color images the way one-shot cameras do.  The downside is that I have to be quick on the draw, changing filters and nabbing frames as fast as possible to get all three colors before Jupiter rotates appreciably, which is a timespan of about 90 seconds.  Luckily, I'm quite practiced at it.  I used my Astronomik RGB filters in my ZWO electronic filter wheel, and I removed the focal reducer for maximum resolution and magnification.  

The laptop I typically use with my primary rig is an old Lenovo from 2012, named Feynman, that I refurbed with a solid-state hard drive.  It performs quite well, but only has USB 2.0, which limits my frame rate to about 1 fps full-frame.  My other data acquisition machine is my Microsoft Surface 3 tablet, named Messier, which is also getting on in years and has been slowing down significantly, even after an operating system clean re-install.  It has USB 3.0, but I knew I wouldn't be able to livestream from it, which I was planning to do with Explore Alliance.  So I decided to spin up my performance laptop, named Cherenkov, which is an MSI I bought myself for Christmas in 2018 for grad school use and star party on-site image processing use.  I moved my table over, and brought out a light so I could be seen on camera, as well as my webcam and mic (the built-in ones on this laptop are terrible).  I got SharpCap Pro and all my camera and filter wheel drivers installed.

Test Drive

I tested out the whole setup on December 18th.  After a couple of issues with not having all the drivers I needed installed, I got everything rolling, and got my Streamlabs OBS settings set up how I wanted.  Once it finally got dark enough to spot them, I got the mount aligned on them and started imaging.  Everything went pretty smoothly -- I have a lot of experience in getting set up now!  

Jupiter and Saturn were already close enough to image at prime focus, without the focal reducer!  I had some trouble processing the images though still.  I even used PIPP to do some pre-alignment, but still couldn't quite get it to go.  I hoped that it would be easier once they were closer together.

The Great Conjunction

The night finally arrived!  I had actually delayed by travel home for Christmas when I bought my plane ticket back in October so I could be at my house for the conjunction.  Dedication :D

There were some clouds in the west before sunset, and I was getting worried.  But they were kind of patchy, so I hoped to at least manage some shots through them.  Fortunately, they cleared out after sunset!  Then it was just a waiting game for Jupiter to become visible so I could align the mount.  I had moved it around since the test drive, so I had to re-align it.  

Since I had put the C8 back on my Paramount for deep-sky imaging, it was out of focus, which would make landing on the planets more difficult and waste precious time.  So I picked up an moved the mount so that I could see the Moon and use it for focusing.  Then I moved it back over to the spot for the conjunction.

Finally, after peeling my eyes, Jupiter finally appeared a half hour after sunset.  Showtime!  I got the scope pointed at it and aligned, got them on the screen, and did some fine focusing.  I immediately started taking videos as soon as everything was ready -- I wasn't going to have much time before they sank below the fence line.  I also streamed the camera's view live on the Explore Alliance show for the conjunction.  

I had to move the mount back a few times to keep the planets in the scope's view -- one downside of such a large aperture is that even though the finderscope was still well above the fence, half the telescope aperture was below it, and the planets were dimming significantly.  After getting a good round of RGB exposures, I took a luminance exposure to get Jupiter's moons, and then removed the camera.  I had promised myself that I would look at them visually, and I am so glad I did!  I threw on the star diagonal and 25mm Plossl eyepiece, and the two planets looked awesome side-by-side. It was super cool to see them so close together.

The Result

I finally managed to get AutoStakkert to play ball by having it only worry about the planet that had the right exposure (since I had to take two different exposure times for their large difference in brightness), and I got the red, green, and blue channels stacked for both Jupiter and Saturn.  I used RegiStax to apply the wavelet deconvolution to sharpen them up, and then I used PixInsight's FFTRegistration script to align each set of RGB frames and combine them into color images.  Then I brought them over to Photoshop to manually composite the Jupiter, Saturn, and Jupiter's moons exposures into a single image, and did some color correction and adjustments.  The final result came out quite nicely, despite how low they were in the sky!

Date: 21 December 2020
UTC: 22 December 2020 02:30
Location: East Bay area backyard, CA
Object: Jupiter-Saturn Great Conjunction
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: ZWO 2-inch 7-position EFW, Astronomik CLS-CCD & RGB Type 2c 2-inch filters
Mount: Celestron NexStar SE
Frames: Best 20% of 250 each
FPS: 15
Exposure: R: Jupiter: 75ms, Saturn: 150ms
  G: Jupiter: 75ms, Saturn: 150ms
  B: Jupiter: 125ms, Saturn: 300ms
  Moons: CLS-CCD filter, 100ms
ISO/Gain: 139
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, PixInsight 1.8.8-7, Photoshop CC 2021

You can only see three of Jupiter's Galilean moons because Ganymede was in transit (but with our current angle to Jupiter, there was no shadow until after Jupiter was too low to see).  

My prep work and practice paid off!  I'm very pleased with the image I got, and I even got to livestream it.  What a night!

Other Fun

Not only was December 21st the night of the Great Conjunction, it was also the night of the first-quarter Moon, and only an hour or two after the conjunction, the Lunar X and Lunar V would both be visible!  The last time I shot the Lunar X was accidentally when I took my very first videos of the Moon using my DSLR on the very same C8 back in May 2016, and I had never imaged the Lunar V.  So I took advantage of not having the focal reducer in place and took some nice Moon shots.  I did move the telescope back over to the Paramount though, since it was going to be a clear night and I wanted to squeeze in another night of deep-sky imaging.  The seeing wasn't great, but they came out all right.

Date: 21 December 2020
UTC: 22 December 2020 02:18
Location: East Bay area backyard, CA
Object: Moon
Attempt: 67
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: ZWO 2-inch 7-position EFW, Astronomik R Type 2c 2-inch filter
Mount: Paramount MyT
Frames: Best 20% of 1,000
FPS: 33
Exposure: 20 ms
ISO/Gain: 0
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, Photoshop CC 2021

I even nabbed RGB videos of Mars before I put the focal reducer, off-axis guider, and focuser back on, although I haven't gotten around to processing it yet.

What a fun-filled night!

Monday, October 12, 2020

#403 - Sunday, October 11, 2020 - Planet-a-palooza!

 We haven't had a whole lot of clear nights here lately, so I have been trying to squeeze in some partial-nights of imaging when I can.  Unfortunately, the right ascension motor on my Celestron CGE Pro mount, the one I use for my science rig (for taking variable star and exoplanet transit data), has died.  So there will be a bit of a break in the science-data-taking while I get another rig set up.  After a talk I gave recently for the AAVSO 2020 webinar series, member Gary Walker, one of the leaders of the Instrumentation & Equipment section, offered to pass along to me a Celestron AVX mount as well as an older QSI 583 CCD camera.  I'm very excited to receive both!  The QSI camera should perform much better than the Orion Deep Space Monochrome Imager II I've been using on the science rig.  My Celestron AVX can't quite handle the 8" Newtonian I use on the science rig, but I think I got one that's on the lower end of their manufacturing tolerance -- I've seen people do better with their AVX's.  So I'm hoping perhaps his will perform better and I can use the Newt with it.  Regardless, it will be put to good use -- I've always got some kind of plan rolling around in my mind. :D

Meanwhile, the plethora of planets in the evening sky has been taunting me for weeks!  Normally I would set up my outreach rig and do some planetary imaging -- my 8" Celestron Schmidt-Cassegrain on my Celestron NexStar SE mount.  However, since I gave up on using my 11" SCT, I've been using the 8" all summer, and plan to keep it on my main imaging rig throughout the winter.  So I decided to spend a few evenings on the planets, and I swapped out my deep sky optics train for the planetary one.

For deep sky imaging, I use a 0.63x focal reducer/field flattener on the C8 to decrease the focal ratio from f/10 to f/6.3 (making the scope "faster") while widening the field of view.  The reducer puts me at an effective focal length of 1280mm, which gives me a large enough field of view to image most nebulae (except for the very largest ones), but not so large that I can't do galaxies and planetary nebulae.  However, for getting the best resolution on solar system objects, you want a looooooong focal length -- as much magnification as you can get away with given the aperture of your scope and the seeing conditions.  I previously used a Celestron 2x Barlow, but always got a bit of chromatic aberration from it, so I finally upgraded to a Baader Hyperion 2.25x earlier this year, and finally gave myself a chance to use it.  So I swapped out the focal reducer for the Barlow, and I also took off my PrimaLuce Esatto focuser because the last time I tried this, I had some trouble with it being too close to the scope and hitting the focuser knob.  

From the scope: SCT-thread to 2" adapter, 2" to 1.25" adapter, Baader Hyperion 2.25x Barlow, ZWO electronic filter wheel, ZWO ASI1600MM Pro

First up: Jupiter

After weeks of wildfire smoke, the air quality app on my phone reported an AQI (air quality index) of less than 10 -- a huge change from the 100-200 we've been having!  And on the few nights it hasn't been smoky, there's been clouds and haze.  But it was crystal clear, finally!  Now I just had to hope that the seeing was good.

The westernmost planet in the lineup is Jupiter, so I started there.  I got several videos on it using SharpCap and rotating through my red, green, and blue filters before it slipped behind my lemon tree, and the seeing was decent, and the image came out all right!  Bonus points: the Great Red Spot was prominently featured, and Europa was just to the side, about to pass behind the planet.

Date: 11 October 2020
UTC: 12 October 2020 02:14
Location: East Bay area backyard, CA
Object: Jupiter (and Europa)
Attempt: 26
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: Baader Hyperion 2.25x Barlow, ZWO 2-inch 7-position EFW, Astronomik RGB Type 2c 2-inch filters
Mount: Paramount MyT
Frames: Best 20% of 1-2,000
FPS: 13-16
Exposure: R: 60 ms
G: 60 ms
B: 75 ms
ISO/Gain: 200
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, PixInsight 1.8.8-6

I am so happy that I took the time to swap out the focal reducer for the Barlow.  Having the extra magnification is making this awesome!  

One of 79 known Jovian moons, Europa was discovered in 1610 by Galileo and is one of the four moons easily visible with binoculars and small telescopes. It's a little smaller than our own Moon, but it has a water ice crust and thin oxygen atmosphere. Due to its very smooth surface, it is thought that a water ocean exists beneath the surface, which could harbor life. Future NASA missions are planned to explore that possibility.

We also have a nice view of the Great Read Spot here. The GRS is a massive storm that has existed for at least the past 360 years, when it was first observed. Within the cyclone, windspeeds can reach 268 miles per hour -- much higher than Earth's hurricanes. The storm is 1.3 times the diameter of the Earth!


Saturn has got to be my favorite to observe visually.  In my C8, it comes in sharp and clear, and it really looks like someone is holding a picture up instead!  I've only come close to imaging it as well as I can see it visually once or twice.

Unfortunately, I spent too long on Jupiter, and Saturn didn't stick around long enough for me to get all three color channels on it, unfortunately.  However, I originally set the scope up for planetary imaging on Friday night, although I only got Saturn before clouds rolled in.  So here's the one from Friday:

Date: 9 October 2020
UTC: 10 October 2020 03:51
Location: Easy Bay area backyard, CA
Object: Saturn
Attempt: 27
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: Baader Hyperion 2.25x Barlow, ZWO 2-inch 7-position EFW, Astronomik RGB Type 2c 2-inch filters
Mount: Paramount MyT
Frames: R: Best 20% of 2,002 frames
G: Best 20% of 2,002 frames
B: Best 20% of 1,848 frames
FPS: 13
Exposure: R: 75 ms
  G: 75 ms
  B: 120 ms
ISO/Gain: 300
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, PixInsight 1.8.8-6

I'm always happy when I get the Cassini division and some detail in the cloud bands.  And I love being able to see the shadow cast by the planet on the rings.  


While I was waiting for Mars to peek out from behind my neighbor's garage, I went and nabbed a more difficult target: Neptune.  I've only imaged it a few times in the past, but it's a lot easier to get into my camera's crosshairs on the Paramount MyT than on my Celestron NexStar SE.  However, I need to make a better pointing model for the MyT; its slews are off by a decent bit, and I wound up having to sync on a nearby star to get Neptune in the image, which required me to go outside and actually look through my red-dot finder because the field-of-view was so small with the Barlow attached (only 13x10 arcsec).  But I finally did get it in my sights.

Date: 11 October 2020
UTC: 12 October 2020 06:22
Location: Easy Bay area backyard, CA
Object: Neptune
Attempt: 4
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: Baader Hyperion 2.25x Barlow, ZWO 2-inch 7-position EFW, Astronomik RGB Type 2c 2-inch filters
Mount: Paramount MyT
Frames: R: Best 20% of 100 frames
G: Best 20% of 100 frames
B: Best 20% of 100 frames
Exposure: R: 3.5s
  G: 3.5s
  B: 3.5s
ISO/Gain: 300
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, PixInsight 1.8.8-6

No gas cloud details for me -- it's just too small!  At only 2.3 arcsec across, that's only 13 pixels wide at my pixel scale.  But still, it's a bluish-green disk, woot!  (Actually the camera didn't capture the color that well for this one -- I think it was too small to do the color calibration correctly.  So I took a guess based on what I've seen in the eyepiece.  It's not really right at all).

Mighty Mars

Mars reaches opposition in October 13th, which is why it is so big and bright in the sky!  Now is the best time to image it.  Luckily for us this year, it's reaching opposition at a time of the year and time of the night when the ecliptic is also quite high in the sky -- it culminates at nearly 58 degrees high for me right now!  Higher altitude = better atmosphere, since you're looking through less of it.

I spent a good chunk of time on Mars, and waited around for times of better seeing.  Of the 5 datasets I collected, #3 came out the best for me.

Date: 11 October 2020
UTC: 12 October 2020 05:22
Location: East Bay area backyard, CA
Object: Mars
Attempt: 19
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: Baader Hyperion 2.25x Barlow, ZWO 2-inch 7-position EFW, Astronomik RGB Type 2c 2-inch filters
Mount: Paramount MyT
Frames: R: 50 ms
G: 50 ms
B: 80 ms
FPS: 20
Exposure: R: Best 20% of 2,004
  G: Best 20% of 2,001
  B: Best 20% of 2,001
ISO/Gain: 139
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax, PixInsight 1.8.8-6

The reddish hue of Mars' surface is a result of the iron oxide that resides in the dust on the surface. Mars has a thin atmosphere, which you can see at the edges of the planet as we look through it edge-wise. It is believed to have had a much more substantial atmosphere, but since the planet lost its protective magnetosphere 4 billion years ago, the solar wind has been stripping it away. The pressure on the surface is about the same as being at 22 miles above the Earth's surface, and it contains only traces of oxygen. 

Visible at the bottom of the planet is the southern polar ice cap, which is a combination of carbon dioxide ice and water ice. The darker areas have less of the red dust, which is why they appear darker.

I managed to get a fair amount of detail -- not the most I've seen from other imagers, but still cool!  I'll need to keep an eye on the seeing forecasts and give it another go here in the near future.

And finally, Uranus

Wrapping up our solar system tour for the evening (very late evening) is Uranus.  By the time I finished Mars, I figured I'd take one dataset on Uranus, and then finally get to bed.  I've also only imaged Uranus twice.

Date: 11 October 2020
UTC: 12 October 2020 06:53
Location: Easy Bay area backyard, CA
Object: Uranus
Attempt: 3
Camera: ZWO ASI1600MM Pro
Telescope: Celestron C8
Accessories: Baader Hyperion 2.25x Barlow, ZWO 2-inch 7-position EFW, Astronomik RGB Type 2c 2-inch filters
Mount: Paramount MyT
Frames: R: Best 20% of 100 frames
G: Best 20% of 100 frames
B: Best 20% of 100 frames
Exposure: R: 1s
  G: 1.5s
  B: 1.5s
ISO/Gain: R: 300
      G, B: 250
Acquisition method: SharpCap Pro
Stacking program: AutoStakkert 3.0.14
Processing program: RegiStax 6, PixInsight 1.8.8-6

Similar story here -- it came out quite gray, so I fuddled with the colors.  But with both Uranus and Neptune, they're definitely disks, not stars!  You can see this visually at the eyepiece really well, which is super cool :D


I need to update my planetary processing tutorial with my new methods, but until I finally have time to do that, here's the rundown.

  • Open the video for each filter in AutoStakkert; auto-place appropriately-sized APs, and then stack the best 20% of frames.  (I have RGB Align ticked so that it aligns the next video to the last.)
  • Open the stacked images in RegiStax and adjust the wavelets.  I prefer to do that in Linear mode -- I've gotten much better results with it.
  • Bring the wavelet-deconvolved images into PixInsight, convert to grayscale (RegiStax likes to save TIFs in RGB), and apply LinearFit to bring each color channel to about the same level (picking one of the filters as the reference).
  • Combine the three color channels using ChannelCombination
  • Correct the color using ColorCalibration, with the whole image used as white reference and a preview box of the background as the background reference.  (I have found this works very well for Mars, Jupiter, and Saturn.)
  • Tweak saturation and the brightness curve with CurveTransformation
  • Use MultiscaleLinearTransform to do a little more shaprening
  • Use MultiscaleLinearTransform again to blur the 1-pixel level, since some weird pixelated hatching tends to result from RegiStax's wavelet deconvolution that looks like debayering when it's not
  • Bring finished image into Photoshop to resize (I shoot my videos cropped to a small window size, usually 640x480, to speed up acquisition & processing and reduce file size).  I usually change the DPI from 72 to 300, and then drop the auto-upscaled size from 450% to like 200-300%, and then do some denoising in Camera Raw Filter as needed.  (This is mainly so that my watermark doesn't look super pixlated when the image gets blown up online).
Planetary processing is much quicker than deep sky.  I can crank through a dataset in about 10 minutes, including the documentation.  There are probably some more techniques I need to learn to get the most out of the wavelet deconvolution, though.

Planets are a fun diversion from deep-sky imaging, and they provide some quick satisfaction!

Friday, July 31, 2020

#379 & #380 - Saturday & Sunday, July 18-19, 2020 - Family camping, auto-guiding the Star Adventurer, and my new trailer!!

In the midst of COVID, time off has been pretty limited, mainly because all of the places one can go on vacation to are shut down in one way or another.  All of the star parties I was planning on going to this summer were cancelled, with the main event I look forward to every year being the Texas Star Party.  After a shelter-in-place spring break, with everything closed or cancelled, I haven't had any vacation time.  So I decided to create some!  I drove home to Spokane, WA to visit my family for a little over a week.

Drive home

It's about a 15-hour drive if you don't include stops, so I took it over two days.  I spent the first night in a town called Redmond, OR, which is just north of Bend.  It's a nice little town with a lot of new construction.  As soon as I pulled in, I began scouting out possible locations at which to shoot Comet NEOWISE!  It didn't take me long to find a good spot: there was a walking trail along a canal that runs through town, and a couple hundred feet down the trail, I found a spot that peaked through the trees to the right altitude & azimuth that the comet would be at later that evening.  I mentally marked the spot, then got some dinner and hung out in the hotel room until dark.

About a half hour after sunset, I took my DSLR, a couple lenses, and my tripod across the street and down the trail to the spot I'd found earlier.  It was off the road, and I hoped the people in the houses along the trail wouldn't be too freaked out by a red-lamp-wearing shadowy stranger lurking on the trail, haha.  I had to scoot down the trail a bit further to avoid disturbing a particularly loud dog.

I wasn't sure how soon after sunset it would be visible, so I got comfy sitting on a rock and waited.  And waited.  And waited.  

Finally, at about 9:45 PM (so about an hour after sunset), I thought I spotted the comet out of the corner of my eye.  I put my 18-55mm lens on and took a shot -- and there it was!

Nikon D5300, 18-55mm lens @ 40mm, 3s, ISO-800, f/5

As the sky slowly darkened, I got the lens focused, and took a series of 6-second exposures at 55mm focal length that I would stack later on.  I took 62 of them, and then swapped out to my 70-300mm lens, set it at 70mm, and took another series of 5-second exposures (adjusted to minimize star trailing).  Next, I set it to 105mm and took a bunch of 5s exposures, although the stars trailed a tiny bit.  And finally, I did a nice zoomed-in 200mm series at 1.3 seconds.

Due to the high rate of field rotation that far north, the shorter-focal-length images had steady stars near the comet nucleus, but pretty streaked stars farther away, showing obvious rotation.  But the 200mm final image has nice, steady stars -- I didn't even have to process it twice to get steady-stars and steady-comet, since the comet was moving relatively slowly against the background of stars.

Date: 15 July 2020
Location: Redmond, OR
Object: Comet C/2020 F3 NEOWISE
Attempt: 2
Camera: Nikon D5300
Telescope: Nikon 70-300mm lens
Mount: Tripod
Exposure: 49x1.3s, f/4.8, ISO-5000

I finally called it quits at about 10:30 PM, since I'd been out there for quite a while already, and needed some good sleep to finish the drive the next day!

Highway 97 through Oregon is a pretty lonely highway, and I've never seen a cop on it, so I usually speed through Oregon at a good clip.  I managed to arrive home on Thursday afternoon just before my mom headed off to work.  My sister and her husband are currently living at home as well, with one out of work due to COVID, and the other working only part-time.  So I had somebody to hang out with while my parents were at work!  They were busy doing other things though, so I just took a seat in the swinging chair on my parent's amazing front porch with a glass of lemonade and enjoyed the great weather until my dad got home early.

Camping trip

My dad took an extended weekend off of work and the five of us, plus my grandparents, took our two trailers up north to my dad's boss's property for a camping weekend.  It was spitting distance from the Canadian border, and although I brought my passport in case we headed up that way, I'm pretty sure Americans aren't allowed into Canada right now!  Crazy to think.

The family of my dad's boss have a whole house built up there in the woods along the Columbia River, as well as a giant shop.  The shop has some sleeping and living quarters, but everyone wanted to feel like we were camping, so my parents slept in their trailer, grandparents slept in their trailer, and my sister & bro-in-law slept in their tent.  My parents had told me not to bother bringing up my tent because of the sleeping area in the shop, but I didn't want to sleep there by myself!  So I cleared out the back of my grandparent's SUV, laid down the seats, and slept in there on my air mattress (which I did bring just in case).  It was a pretty tight squeeze, but I've been meaning to test out car-camping, so it was kind of fun!

We did some lounging around and some fishing in the evening, and while the fishing was going on, you can probably guess what I was doing -- setting up gear!  Since I drove up instead of flying, I could bring up whatever gear I wanted, but I decided not to bring a whole telescope rig because that far north, astronomical darkness only lasts for about three hours.  So instead, I brought my Sky-Watcher Star Adventurer, ZWO ASI294MC Pro, and 55-200mm camera lens that I had attached to my Celestron AVX mount in my backyard.  Since it was quite dark up there -- Bortle 2-ish -- I wanted to swap out the Orion SkyGlow filter for just a UV/IR cut filter.  The Orion SkyGlow filter is SCT-threaded, so I needed a different solution.  Working an M48-threaded filter into a camera lens setup is tricky, so I wound up putting my 1.25" Astronomik Luminance filter inside a manual filter wheel I haven't used in a white, which was nearly the same thickness as the SkyGlow filter for back-focus purposes.  While I did measure it with my calipers, I didn't get a chance to double-check that it would come to focus, so I brought along some extra spacers and adapters just in case.  (Different filters have different indices of refraction, which move the focal point around by a couple of millimetres).  

In addition to all this, I brought a couple extra things to do another experiment I've been wanting to do for quite some time, which was auto-guiding the Star Adventurer.  It has two camera connection points on it, and I finally had acquired all the adapters I needed to put my Orion 50mm mini-guider attached to a QHY5 guide camera on it.  The Star Adventurer uses ST-4 guiding, not USB, and only the RA axis is motorized, but my expectation was that it would at least help clean up the tracking enough to allow for longer exposures, especially if I was well-polar-aligned.  ST-4 guiding works by plugging the guide camera into your computer via USB, running PHD2, choosing "On-camera" for the mount, and then plugging the camera via ST-4 cable (the wider telephone-looking one) into the mount.  So PHD2 doesn't talk directly to the mount, but rather sends the command through the camera to go to the mount.  It's an older, and largely obsolete, method of autoguiding (pulse guiding is much better), but it still works for mounts that don't support USB guiding!  The major downside to ST-4 guiding is that because PHD isn't talking to the mount, it doesn't know what the telescope's declination is (which affects the calibration and the length of pulses it needs to send), so you have to tell it yourself, and re-calibrate every time you change targets (although I think Sequence Generator Pro can actually handle this).  But since the Star Adventurer isn't a goto mount, just a "dumb tracker," I'm only doing one target at a time anyway, so it's a non-issue.

There was power up there, but I forgot to bring the AC-DC adapter for the cooler on my ZWO camera, so I just ran that off the battery.

The back deck was pretty shaky, but there wasn't a good spot on the pavement to see the North Star from, and the sprinklers were running on the grass (yes, they had a lawn, and yes, it had sprinklers...sheesh!)  So I just told everyone to stay off the patio after dark.

Setup actually went pretty smoothly: I used the Polar Alignment app on Android (there's something like it on iPhone too I think) to plant the North Star at the right place on the "clock" in the polarscope for the time and date; did some star-hopping in the red-dot finder I had for the ZWO camera to land approximately where I wanted to image (the Elephant Trunk nebula up in Cygnus; it was dark enough that I could hop to the Garnet Star at the edge of the nebula with ease, and then guesstimate from there where to center the camera); set up PHD2 to guide in just RA and got it calibrated on the first try, and then just let it run once I saw the first 3-minute frame come down looking pretty good (after sitting very still).  I couldn't check on progress remotely because there was no cell signal up there to create a wifi network to remote into my computer from, and I didn't want to rattle the deck by walking on it over to my computer, so I just let it be and crossed my fingers.  Most of the frames turned out pretty well actually, and I imaged the same spot the next night as well.

One of the benefits of camping so far north (48N latitude) was that Comet NEOWISE was quite high in the sky, sitting at 22 degrees high at 9:45 PM, and still 12 degrees high when it was nice and dark at 11:45 PM.  My grandparents were very excited to see it through a break in the trees; it was fairly obvious naked-eye still that night, and looked great in binoculars and in the camera.  I think the rest of my family got a kick out of seeing it as well.  And I got some nice shots!

Nikon D5300, Nikkor 35mm f/1.8G lens, 20s, ISO-6400, f/2.2
We had the lights from the town of Trail across the border to the north, but overall it was quite dark!

My dad and brother-in-law managed to catch only two walleye, but we prepared them and cooked them up over the campfire for some delicious fried dessert bites.  

My sister Mary's turn with the rod

Parents & grandparents at the fire pit

The weekend came to a close all too soon on Monday, and we packed up and headed back to Spokane.  It was a really nice, relaxing weekend!  And then I had the rest of the week to process my images, since I brought my laptop with me.

Imaging Results

The Elephant Trunk Nebula image came out pretty decently given that I just used a color camera and no narrowband!  I was a little bit off-target in my aiming, but actually quite close for doing it by hand!

Date: 18, 19 July 2020
Location: North of Northport, WA
Object: IC 1396 Elephant Trunk Nebula
Attempt: 4
Camera: ZWO ASI294MC Pro
Telescope: Nikon Nikkor 55-200mm f/4-5.6 @ 200mm, f-something (toothpicks)
Accessories: Astronomik L Type 2c 1.25" filter
Mount: Sky-Watcher Star Adventurer
Guide scope: Orion 50mm mini-guider (ST-4)
Guide camera: QHY5
Subframes: 18x180s (54m)
Gain/ISO: 120
Acquisition method: Sequence Generator Pro
Stacking program: PixInsight 1.8.8-5
Post-Processing program: PixInsight 1.8.8-5
Darks: 100
Biases: 0
Flats: 0
Temperature: -10C

Now, the actual Elephant Trunk is hard to see -- if you start at the Garnet Star (the bright yellowish one on the left), and scoot directly to the right, passing over the U-shaped dark nebula, you can just see the formation of the tip of the Elephant Trunk before you hit the next streak of dark nebula to its right.  (I recommend clicking the image to blow it up to see it).  I got some red nebulosity, nice dark nebula, and pretty good-looking stars for this camera lens!

I also ran around with my DSLR and 35mm f/1.8 lens to get some nice Milky Way shots!

Nikon D5300, Nikkor 35mm f/1.8G lens at f/2, 8s exposure, ISO-6400
That's Jupiter peaking its face up from behind the hills there!

I also attempted some panoramas, which I haven't processed yet.

At long last, the AstronoMolly-Mobile!

Back when I used to camp at my astronomy club's observatory grounds when I lived in the Midwest, I was usually one of the only tent campers -- most of the rest of the gang who came out had those fancy trailers.  My grandparents lived in an RV for about 20 years after my grandpa's retirement, and my parents started trailer-camping a couple of years ago, but I am still perfectly happy tent camping.  For regular camping trips, that is -- tent camping becomes more difficult when doing astronomy.  This is largely because of getting adequate sleep; it's hard to sleep in when it gets very bright and very hot early in the morning.  (Or very cold at night too, in some places!)  And while I've been camping more times than I can count throughout my life, 7 nights tent-camping at someplace like the Okie-Tex Star Party sounds kind of not-fun.  And now with bathrooms closed at campgrounds and other public places due to COVID, it's even harder.  It is finally time to make a purchase I've been planning for a couple of years now: a trailer!

So I drive a 2017 Ford Escape, the 4-cylinder 2.0 L Ecoboost variety, which is in the compact SUV class.  Most compact SUVs can only tow 1-2,000 lbs, but the Escape was built on a truck chassis, and paired with the Ecoboost turbo, it's rated to tow 3,500 lbs.  Now, since it is only a 4-cylinder, I was pretty sure that 3,500 lbs was not going to do very well, so my plan was to stick somewhere sub-2200 lbs dry.  There are lots of soft-sided campers that fit the bill, but I didn't want soft-sided (both for protection from wildlife and holding in heat/cool).  I also wanted a toilet of some kind, and there were some hard-sided A-frame-type campers I was looking at as well that had cassette toilets and pop-up wetbath walls.  There are also plenty of small trailers out there, but most are 2500+ lbs, with probably too much frontal area to tow comfortably in my Escape (the manual says to keep it below 30 square feet).  

In my internet searches, particularly when I was looking for user experiences in towing with my car type, a brand I hadn't come across previously was mentioned quite a lot: Nucamp T@bs.  They're little trailers, but not pop-up campers that I had been looking at before.  After seeing what was available at the local RV dealerships, my parents and I went to RnR RV, which had a couple small trailers at their Liberty Lake location, and a couple more at their North Spokane location.  We went to Liberty Lake, since it was a faster drive, and my grandparents had bought from them before.

On the showroom floor was a T@b 320 S, which was little but packed with features, and only weighed 1900 lbs!  It was perfect.  The dealer took me out to the lot to look at a used version and another light trailer, but when we came back in, that T@b had been sold out from under me!!  The used one was only one model year old, 2019, and was nearly the same price as the new one (they hold their value pretty well, like Subarus).  So the dealer looked up what was available at their other location, and lo and behold, there was another T@b 320 S.  But, even better -- it was this incredible white and red color!  Super cute :D And astronomy-red!  It was pricier than the more boringly-colored one there because it had the Boondock package, but we convinced him to lower the price to nearly-match the one there.  It was terrifying and exciting, but it ticked nearly all of the boxes of both what I needed and what I wanted, so I bought it! :D  They pulled it down to the Liberty Lake location, and I came back later in the week to pick it up, do the walkthrough, and have my car modified (replaced the 4-pin electrical connector with a 7-pin and added the electronic braking system control unit).  It is perfection :D

It took me several attempts to get it backed mostly-straight into my driveway, but I did it!

The table is fully-articulating -- it moves in a circle, can be pushed and pulled to one side or another, and raises and lowers.  It also can be removed and re-attached outside on the side of the trailer.
The back of the couch-seat there folds down into a space where, if I set up slightly diagonally, I can set up a place to sleep without having to take the table out, and there's still room to sit on either side of the table!

That's a little TV there on the left, with air conditioning and heat/electricity/hot water controls above it.
The kitchenette includes a sink, two-burner gas stove, and 3-way fridge (AC, DC, and gas).
There are four windows that all open outward, and each has both a draw-down screen and draw-up privacy shade.  The door also has a little porthole window that has its own privacy screen.

Yes, it has a toilet and a shower!!  I can't quite stand in the shower, so it'll be a seated shower whenever I do take one in there.

I've already had a bunch of my neighbors come by to admire it!  It's just so darn cute!
As far as other stats go, it has a single propane tank and battery on the front, a reversible, multi-speed (and honestly pretty quiet) fan on the roof, a tankless water heater, no outside storage (but I'll be strapping a bin to the front to hold my hoses and electrical cables), a 10-gallon freshwater tank, 10-gallon graywater tank, and 5-gallon blackwater tank, AC power connection (30 amp), solar power connection (to trickle-charge the battery), racks on the back for other outdoor gear, and LED lights on the front and back for illuminating your site.  Also, the cabinets are actual wood, made by the Amish.  (The trailer included a picture and signed card from the crew that made them!).  The outside is fiberglass.  

Driving it home from Washington back to California went pretty well, actually.  I had little trouble getting it on my hitch and all hooked up by myself the morning I left (thanks largely to my backup camera!).  I don't really feel the trailer on city streets, and didn't start to feel it on the highway until about 60 mph, when the drag became great enough to feel.  (The super-off-road tires I'm sure don't help with that situation!).  Downhills were no sweat with the electronic braking system, but uphills made the motor work a little harder.  I eventually had to just go 50-55 on uphills to keep the motor below the 4-5,000 rpm range.  Engine temperature never left normal, but my gas mileage sure did suffer!  I averaged about 12.5 mpg coming over the Sierras and then through the vineyards and desert-y parts of CA on the way back to the bay on I-5.  So it took a little longer to get back, but really not too bad.  (Although I definitely won't be going 80 mph on that interstate through Texas to the Texas Star Party next year though!).  It only fishtailed a bit once when the road was a little rough and a gust of wind caught me by surprise, but it was easy enough to regain control by just letting my foot off the gas and not moving the steering wheel.  I did a little reading, and it sounds like I can also tap the braking system control to apply the trailer brakes a bit to bring it back under control.  

All in all, it's the perfect trailer for singular me and the many astro-camping trips and star parties in my future!

The new AstronoMolly Mobile Observatory!

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