Sunday, January 12, 2020

#274 - Saturday, January 11, 2020

Before making dinner and then heading out to the Eastbay Astronomical Society meeting, I got my scopes setup -- my Takahashi FSQ-106N on my Paramount MyT, with my ZWO ASI1600MM Pro camera and Astronomik H-alpha filter, as well as my recently-built astro camera rig, my ZWO ASI294MC Pro with my Nikon 70-300mm lens and the Astronomik CLS-CCD filter, all loaded onto my Celestron AVX mount.  In addition, since I had two rigs running, I thought it might be fun to do another timelapse, so I set up one of my DSLRs on a tripod to do that.

While at the meeting, I remoted into my data acquisition machine to make sure everything got started up smoothly -- and it did indeed!  So satisfying when things just work :D

Tracking on the AVX was looking good.  On the Paramount, I couldn't remember if I had re-calibrated guiding in PHD after re-building the mount after going home for Christmas.  Since I left my guide camera and guide scope attached to the main telescope the whole time, I shouldn't have to re-calibrate, but you never know when things get knocked a little off-kilter.  So I re-calibrated it anyway.

I went through the frames in the morning -- a few sets of thin clouds had rolled through periodically, but I still got quite a few frames over the course of the night.  One of my Orion constellation widefield frames through the camera lens had some satellites pass through -- one was a really bright, single streak, although I couldn't find it in SkySafari or Heavens Above.  Another was actually two side-by-side, and with one tumbling (you can tell it's tumbling because the light is brighter and dimmer across the frame).  I couldn't identify what they were either; potentially a tumbling rocket body.

Given how bright this one is, it's very possible that it's actually an airplane, but at a high enough altitude that you can only see one streak.

You'll have to ignore the fact that the streaks are red -- these are non-color-corrected screenshots from the raw image file.

And here's the timelapse!



Friday, January 10, 2020

#273 - Thursday, January 9, 2020 - An ""Astro-Modified DSLR""

A problem with DSLR cameras is that they have a spectrum filter on them to make the images look very close in color to how the human eye perceives it.  While great for daytime imaging, it inhibits the camera's performance for astrophotography, particularly because like the human eye, the spectrum filter passes very little red light.  Of course, if you've seen all of the nebula images I've taken, there is quite a lot of red-glowing gas out there in the universe.  This makes sense, considering that hydrogen is by far the most abundant element, and that red glow is from hydrogen!

There are services out there that will remove the spectrum filter from your DSLR for a couple hundred bucks, and Canon, Nikon, and Sony (and probably some others) sell astro versions of at least one of their cameras (although they are pricey!).  The thing is, after spending all that money, you still don't have a cooled camera.  So while it may be more sensitive to red, it's still going to be just as noisy.

Instead of spending $2,500 for the Canon EOS Ra, or $3,800 for the Nikon 810a, you can spend $1,000 for a cooled astrophotography-specific camera, like the ZWO ASI294MC Pro.  No spectrum filter (or UV/IR filter for that matter -- useful for imaging the planets in UV and IR), and it's cooled.  So an experiment I've been wanting to try for a while is using a color astro camera with a camera lens to do some widefield stuff.  (I also want to capture hydrogen alpha data with a monochrome camera, but that experiment will happen later).  I finally had the chance to assemble that setup this past weekend, after I bought a T-thread-to-Nikon bayonet adapter.  I couldn't use it right away last weekend because I didn't quite have the spacing correct -- I needed a little bit less separation between the lens and the camera in order to bring it to focus at infinity.  The solution was to swap out the female-threaded connector on the filter wheel with a male-threaded one so that I could attach my ZWO camera directly to the wheel without the male-to-female adapter ring that adds a couple of millimeters.  (The Starlight Xpress filter wheel has removable connectors so that you can attach the size/thread that you need).

From left to right: Nikon 70-300mm zoom lens, M42-Nikon bayonet adapter, Starlight Xpress filter wheel, ZWO ASI294MC Pro attached without the male-to-female M42 ring.  (M42 and T-thread are talking about the same thing).
The silver clamp is one that ZWO sells for their cameras.

I connected the camera to my tablet once again and pointed it out the window at a power pole across the street.  I focused the lens, and I was able to bring it into focus!!


The next step was to actually get it attached to my mount.  The clamp from ZWO has a tripod-sized connection, not a Vixen-sized one, so I needed a way to bolt it to a Vixen dovetail.  I tried just bolting it to a spare one I had, but the side with the grooves in it so that the bolt head would not interfere with actually attaching it to the mount was on the wrong side for the polarity to be right to attach the dovetail rail to the mount.  (Sorry, hard to explain without pictures...which I forgot to take).  So instead, I grabbed this short wooden dovetail I had from another scope, which has a few 1/4-inch holes in it, and attached it to that.  Got it all connected!  I attached it to my Celestron AVX mount.

 

It was getting darker as I finished putting things together, so it was time to grab the laptops and get rolling.  In addition to this novel rig, I also ran my Takahashi FSQ-106N refractor with my ZWO ASI1600MM Pro and a hydrogen-alpha filter atop my Paramount MyT.  Over on the AVX with the camera lens, I slewed to Aldeberan to focus (I left the mount aligned from when I had another telescope on it), and I added a calibration point after centering it.  To focus, I grabbed a tiny Bahtinov mask perfect for camera lenses that I had, but even with 2-second exspoures, a high gain, and a super stretch on the histogram, I couldn't quite see all three diffraction spikes with the lens at 70mm.  So I got it somewhat focused with that, and then getting the star as small as possible.  There was a little ring around the star because my lens is pretty achromatic, but it did, indeed, come to focus!  Very exciting.

The next challenge was trying to get the plate solver to work so that I could get targets accurately centered.  I messed around with the settings in PlateSolve2, which is the plate solve program by PlaneWave that I use within SequenceGenerator Pro, but couldn't get it to successfully plate solve -- I think the images were just too big of a field, at 15x10 degrees.  I also didn't see a way for it to use a subframe or a ROI (region of interest).  After some Googling, I ended up just using Astrometry.net's online blind plate  solver, which is much slower, but it worked!

The first target I queued up in SGP is one I've been wanting to do with a "spectrum-modified" camera for a while, which is an Orion constellation widefield, including Barnard's Loop.  It wouldn't be high enough until 8 PM though, so I added a widefield of the Taurus region, to get M45 (Pleaides Cluster) on one side of the frame, and the California Nebula on the other. 

After a couple of subframes came down looking at Taurus, I took a look at them and remembered that this lens has quite a lot of curvature -- I can really only use about the inner half to 2/3rds of it.  The framing at 70mm put M45 and the California Nebula both in the nasty part of either side of the lens, so I changed the target location to center M45 instead.  When it was slewing there, it took a weirdly long time (I was doing this from indoors), so I thought maybe it was meridian-flipping.  But it shouldn't have been time for that yet.  The plate solve solution was also waaaay far off in right ascension, and it wasn't getting better as SGP re-centered my mount.  So I went outside to see what was up, and yes, it did flip, but it was hitting my software slew limit for that side of the pier.  (I have it set to not go beyond 90 degrees, aka straight up, since my AVX has a loose dec axis, and the axis can slip out from the gears, causing problems).  For some reason, my AVX keeps resetting the meridian setting to "favor west," so I disabled the meridian setting (again) and went back inside.  When I re-started the sequence, it went back over to looking at the eastern sky -- perfect.  While it started imaging, I went to work figuring out what target to have it do after the Orion constellation. 

Single 5-minute subframe on the Pleiades Cluster with my 70mm lens and ZWO ASI294MC Pro (with a light pollution filter)

Back over on the Takahashi, the sequence hadn't actually started yet because the cooler on the camera hadn't reached the set temperature yet.  But it had been running for a while...it was only at 0.5C, and only 12% power!  Why?  And it wasn't increasing the power.  Ah crap.  Did I mess something up when I opened it up to clean the sensor?  I connected it to SharpCap and turned on the cooler there, and it seemed to function normally.  Phew!  So I disconnected and reconnected everything in SGP and restarted the program, and then it worked normally after that.  Weird.

Meanwhile, my first Orion constellation image came down -- I could see M42 quite well, the Flame and Horsehead Nebulae a bit, but no Barnard Nebula.  It was probably buried in the light pollution, I figured -- it's also a full Moon tonight.  So I changed the exposure time from 3 minutes to flipping back and forth between 1 minute and 5 minutes.

Single 3-minute frame on the Orion's Belt area, 70mm camera lens, ZWO ASI294MC Pro (with a light pollution filter)  

It was 8 PM then, time to go make some dinner!  Before doing that, I added a few more targets I came up with to the camera lens sequence: the Seagull Nebula (probably won't come out well, but why not try), the Beehive Cluster (I don't typically do open clusters, but I needed something), and the Coma Berenices region centered on the Needle Galaxy.

In the morning, I went to check on things; the Paramount setup aborted due to a failed meridian flip at some point, and didn't run my last target for the night, galaxy M106.  I also only get one frame on the Medusa Nebula.  I went through the log, but couldn't quite figure out what exactly made it abort.  In addition, I forgot to tick the "run" box for the 5-minute-long frames, so they didn't run.  On the other hand, the sequence for the camera lens over on the AVX ran all night and completed successfully.

We shall see how this experiment turns out!




Tuesday, January 7, 2020

#272 - Monday, January 6, 2020 - Errors, Errors Er'ywhere

Yet another clear night! :D:D Winter is shaping up to not be so bad around here...

With a fattening Moon, I imaged it in twilight before connecting the rest of my gear.


It's just so darn pretty through the refractor.  The hydrogen alpha filter also helps, since the red wavelength of light it passes is less disturbed by the atmosphere than bluer shades, so it's nice and sharp.  

Despite how well things went last night, things can't go well for too long -- that would violate Murphy's Law!  Which everyone knows is scientific fact. ;} Sequence Generator Pro would not talk to PHD, the autoguiding software.  It kept saying that it wouldn't accept pulse guide commands.  I haven't changed anything, I swear!  So I messed around with the TheSkyX driver settings some more (whoever puts "the" in their software name is slightly annoying.).  I ticked the "Enable Tracking Offsets" and "Enable PulseGuide", and unticked "Use DirectGuide."


I'm not sure what settings I had previously to make it work, but this did seem to work -- the mount connected, and guiding worked fine.  Well, about as fine as it has been the last couple of nights, which has not been stellar...like 1.8 arcsecond RMS.  At 10 minute exposures, the stars do elongate a bit with that kind of error.  It's mostly in RA; declination showed much smaller error, around 0.5 arcsec.  One of my astro-buddies on the The Astro Imaging Channel (and again...), Terry, suggested I check for any cable tug.  This could very well be the case, since I recently took everything apart and put it all back together when I went home for Christmas.  My cable bundle was a little tight from where I had it attached to the mount base up to where it's attached to the dovetail saddle when it's rolled all the way over to point south, so I unhooked it from the mount base because I couldn't find a better spot to secure it.  I'll work on that.

That little fix didn't improve the guiding, however.  I disabled PEC (periodic error correction) in TheSkyX just to see, but that didn't make a difference either.  I'm not sure why it's suddenly not great.


I checked in on the system around 9:45 PM, and it was erroring out!  The mount had disconnected from TheSkyX, which was reporting a loss of communications error, which was weird.  So I went out to check the cables, and they looked fine, so I disconnected and reconnected the mount USB cable.  TheSkyX still wouldn't connect, so I disconnected everything in all my software, unplugged and replugged the main USB cable, and tried again.  TSX finally worked again, so I restarted the sequence and went back inside.  

After washing the dinner dishes, I checked again, and it wasn't erroring, but Sequence Generator Pro was stuck on "resuming guider."  PHD was unable to talk to the camera, as it turned out.  This happens fairly often when I disconnect the USB cable from the guide camera while PHD is still open, even if I disconnected it from PHD first.  So I restarted PHD, and it worked fine.  But a few minutes later, it errored again, with TSX reporting loss of communications once again.  So maybe my USB hub was breaking down?  I ran inside and grabbed one from one of my other cable bundles that I wasn't using and swapped it out.  It seemed to be holding after that -- phew!


I went online to come up with one more target for the early morning hours, and settled on getting some H-alpha data for the galaxy M106.  I have some color data of it already from this same scope and camera, so now I'm going to add some H-alpha to it!

Zoomed in on M106, 10-minute single subframe, H-alpha filter.


Monday, January 6, 2020

#271 - Sunday, January 5, 2020 - A New Kind of Problem

Camera sensor


In astrophotography, as with just about anything that has mechanical or digital components, things are always breaking down.  If it's not one thing, it's another!  While I continue to make progress on getting my new mount to work smoothly, I had a new kind of issue today, this time with my camera!

I went outside to swap out my color camera for my monochrome camera on the Takahashi refractor, and I remembered a really weird pattern I saw on the mono camera's sensor (ZWO ASI1600MM Pro) when I was aligning the Celestron AVX mount.  I didn't get a screenshot, but it was like a row of smallish shadow-dots.  I looked at the business end of the camera, and sure enough, there was the line of tiny dots on the window.  So I grabbed a cotton swab and gently touched it to the window, but the dots were not coming off -- in fact, after tilting it at various angles, it became obvious that they were actually not on the window, but the sensor face itself!


I consulted the manual, and it looks like it's not warranty-voiding to open it up.  In fact, there are instructions in the manual on how to do it!  So I removed the T-thread ring and the top plate with the window and sure enough, there was something on the sensor, or possibly it had delaminated a bit.  I touched it with a clean cotton swab, and it seemed kind of greasy.


I wondered if some of the sealing grease around the front plate had somehow dripped inside while it was hanging upside-down from the Newtonian.  The manual said to clean the sensor with ethanol, so I went down the street to my local hardware store to see if they had some, but apparently it's difficult to come by in California.  They said I could maybe try a marine supply store.  I went online to see if isopropyl alcohol might work, but lots of people on forums warned that even the 99% variety, which is about the highest purity you can get, still has enough water in it to make streaks on the sensor.  Lots of people also recommended this camera sensor cleaner called Eclipse, so I went online to Amazon and ordered that plus some lint-free cotton swabs.  So I did what I could with just a cotton swab, which seemed to pick up at least some of it, and then sealed it back up.  

It looks like I got most of it off.

For those of you cringing at the thought of opening up your camera -- worry not, I'm a professional!  I've worked with some pretty sensitive equipment, being an experimental physicist.

When you open the sensor area, there are four dessicant tabs that you have to re-charge, since they get exposed to the air and immediately start collecting moisture.  The manual said to microwave the tabs for 2 minutes, so I did that.  With about 45 seconds left, I smelled something burning...I double-checked the manual, and it said 2 minutes at medium power.  Crap!  I stopped the microwave with 20 seconds left, and the tabs did look a little toasted.  But I put them back in anyway.  You have to do this quickly before they start absorbing water.  I'll see how things go, and see if I need to order new tabs.  If the window starts to dew up, I'll know.

A new side-project


My other afternoon project was getting my color camera, my ZWO ASI294MC Pro, set up with a camera lens.  I was going to have to play around a bit with the spacing to see if I could bring it to focus.  My first attempt was the camera, then the filter wheel (yes it's a color camera, but it's the easiest way to get my light pollution filter into the optics train, and then it'll be easier to swap my mono camera in and out), then my 70-300mm lens, since it has manual aperture, unlike my other lenses.  My other lenses have their irises closed until the camera tells them to open, so I was going to have to use my one manual-aperture lens.  

I set up the contraption on the ZWO camera ring, which has one of those little dovetails that goes onto a camera tripod or ball mount, and put it on my tripod, pointing out the window.  

My cat, Orion, was "helping!"
Optic order: lens, Nikon bayonet-to-T-thread (M42) adapter, Starlight Xpress filter wheel, T-thread ring, then ZWO camera.  The clamp is one that ZWO sells specifically for its ASI cameras.

I connected the camera to my tablet and powered it up, and then tried to focus on a power pole on the street behind me.  Unfortunately, it did not quite make it.  It looked like I needed to have the camera close to the lens for it to focus.  I thought I might also try another lens, just to see, even if the aperture was small.  I looked at how the aperture opens on the lens -- as it turns out, there's just a little lever that gets moved back and forth.  So, I went to my kitchen cupboard and got a toothpick, broke it into pieces, and stuck the pieces into the hole so that the lever was held open.  The bayonet adapter had empty space around that part, so even though the toothpick ends stuck up a bit, they didn't hit the adapter.  Sweet!  That's one problem solved.  Now I can use my other lenses.

Using toothpicks to hold the aperture open on my Nikon 50-200mm lens.

In order to get the camera closer to the lens, I needed to get creative with adapters.  In the manual and in some posts on the ZWO Facebook group, I saw that people attached the filter wheel directly to the camera, without using the T-thread ring.  But that ring also flips polarity -- the camera, without it, has a male T-thread connection.  This meant I needed a female connector on my filter wheel instead of the male one that was there.  Luckily, Starlight Xpress sells a variety of different connectors, and they come off with just two outside-accessible screws.  So for $30 on Oceanside Photo & Telescope's site, I got a female connector for it.  Woot!  Should be coming soon.

To get an idea of the spacing, I took out the filter wheel, and just held the camera so that I could make sure that I could get close enough just by removing the ring.  It only needed to be a few millimeters closer to achieve focus at infinity, woo hoo!  So this should work.  Can't wait!

Nighttime imaging

Night fell, and it was crystal clear!  Tomorrow night looks good too.  The Moon was waxing gibbous, so I put the ZWO ASI1600MM Pro mono camera on my Takahashi refractor with my hydrogen alpha filter.  Yes, the moon reflects the Sun's H-alpha light too, but as long as you stay about 40 degrees away or so (depending on phase), you can still get a low enough background to image.  On tonight's menu of photons for the camera to chomp on was the Pacman Nebula, Flaming Star Nebula, Cone Nebula, and Medusa Nebula.  Thanks to meridian flipping now working, this list takes me through to 3 AM, woot!  After that, the only targets up are the little itty bitty galaxies of the upcoming springtime Galaxy Season, which are too small for my 106mm, f/5 refractor.  Once the Moon goes back down, I'll probably go ahead and swap out for my 11-inch Schmidt-Cassegrain to start bagging the bitty bois.

Since the Moon was up, I went ahead and grabbed a video of it before it was astro-dark.  I wanted to process it right away, so I tried to drop it into OneDrive and have it sync across my wifi, but it just said "sync pending" for forever, so I paused the sequence, unplugged the focuser (I needed a USB port, and it was the easiest to re-connect to), plugged my USB 3.0 flash drive in, and waited about 5 minutes for it to transfer.  I processed it, and it's not too shabby!

Honestly, it's gorgeous.  Just sayin'. :D

The sequence ran smoothly, and the images came out beautifully.  I didn't see any sign of the residue on the subframes.  When I checked on them in the morning, the stars were a little elongated in many of the frames.  Maybe there is some cable-tug?  I also took a new set of flats in the morning for putting the camera back on.  

10-minute H-alpha subframe on the Flaming Star Nebula



Sunday, January 5, 2020

#270 - Saturday, January 4, 2020

On Friday night, I didn't set up imaging because the forecast called for rain in the morning, but I did spend a little time in the evening hunting down the meridian flip problem.  I did some Googling, and one forum post said that you need to change the hour angle setting in TheSkyX to be 0 in the BisqueTCS settings, which has to do with the angle that the mount will flip itself at.  So I did that, and tested it on a star that was about to cross the meridian, and Sequence Generator Pro was able to issue the flip command, and it worked!  So hopefully that's the end of that problem.  Most of the other posts I came across were from 2016 and 2017 before some changes were made in the TSX driver and in SGP.

Tonight, it won't be properly clear until after 1 AM according to the forecast, but it was clear enough to get started around 6:45 PM.  There was a ring around the Moon, but at least I could get things rolling.

After getting the Paramount setup and rolling, I went over to my Celestron AVX with my 8-inch Vixen f/4 Newtonian on it.  My plan was to align and polar align the mount with that scope, since it would be more accurate, and then swap it out for either the Soviet Maksutov-Cassegrain camera lens I have, or one of my Nikon camera lenses, attached to my ZWO ASI294MC Pro.  I finished aligning the AVX, and was about to polar align using Hamal, but it was too close to the meridian, and the dec axis slipped out a bit, causing the gears to do the crazy, loud back-and-forth motion they sometimes do for various reasons.  So I had to shut off and reboot the mount, and after re-aligning, I used Rigel instead for polar alignment, since it was too cloudy to use a more well-placed but dimmer star.  It's best to use a star near 0 declination and near the meridian for doing Celestron's All-Star polar alignment.

Once that was all done, I parked and hibernated the mount, and covered it back up and took darks.  I'll work on getting either one of the camera lenses set up tomorrow or Monday.  I might do the Russian lens, but I also really want to do a wider FOV camera lens and try for getting the deep red H-alpha signal of Barnard's Loop and the Orion constellation area, with my color camera and light pollution filter.  We shall see!

Around 7:40 PM, I finally went inside to make dinner.  The clouds had cleared out, the ring around the Moon was gone, and the M45 area was pretty clear, which is where my sequence was at.

I checked in on my computer from my phone (using TeamViewer) around 10:30 PM and saw that the sequence was in recovery mode and the plate solve image was blank.  Huh?  Why was it blank?  Also, why was it plate solving right now?  PHD's guide camera view showed a white image too, like a thick cloud.  So I went outside to see if it was pointing somewhere weird or if it had clouded over, but no, it was clear as a bell outside!  I opened the folder where my images were saved, and the last one was captured at 9:50.  Oof.  I don't know what the heck happened.  Maybe a freak cloud rolled through?  But then the sequence finally recovered on its own and continued imaging.

I checked again at 11:25 PM, and the meridian flip on the Orion-area nebula M78 at 11 PM was successful!  It was happily snapping away.  It looked like PHD was guiding fine too, so the calibration coordinates must have been flipped like they were supposed to.  Woot!  Glad I finally got that issue fixed.

Checking on things in the morning, I only got a couple frames on the Cone Nebula, although I'm not sure why.  I got quite a few on M45, the Pleaides Cluster, but it looks like some thin clouds might have drifted through.  I got a fair few shots of M78 and the Medusa Nebula, and a whopping 30 frames on the Whale Galaxy!

5-minute color frame on nebula M78 from my Takahashi refractor

5-minute color frame on M45, the Pleaides Cluster



Friday, January 3, 2020

#269 - Thursday, January 2, 2020 - A Little Visual Observing

The forecast looked like it would be intermittently clear with only a few clouds, according to my new favorite astro forecast app Astropheric (they have an Android app too, not sure about iOS), so I decided to go ahead and image, because why not!

I successfully imported the panorama I took yesterday into SkySafari!


I tried bringing it into TheSkyX as well, but the settings only allow you to have the top of the picture be 45 degrees high, and I, unfortunately, have obstructions taller than that, like 60 degrees.  So I'll just have to use SkySafari to know in advance of slewing whether something is visible.

I got the sequence rolling with my ZWO ASI294MC Pro color camera on my Takahashi FSQ-106N refractor on my Paramount MyT, and then I headed inside.  Watching from my computer indoors, the guide camera was still able to see guide stars, and the guiding actually looked pretty decent.  No errors yet from Sequence Generator Pro.  

I went outside later to see how the sky looked, and it was quite nice, actually!  There were some thin clouds toward the east but low in the sky, and low in the south as well, but up above about 45 degrees it looked very nice indeed, and the seeing appeared steady.  It was so nice that I even went back inside and grabbed my little Meade 10x42 binoculars.  I observed:
- M42 Orion Nebula, which was a fuzzy patch with a couple distinct stars
- M45 Pleiades cluster, which looked very nice, of course
- Tried for the Beehive Cluster, but had a hard time finding it; perhaps a bit small for my binoculars, and the clouds were a little thicker where it was at
- Double Cluster, which took a bit to spot, but I could see two speckly fuzzy lumps
- M31 Andromeda Galaxy, which was a faint fuzzball but it was there
- I also caught the Hyades Cluster on my way to looking for the Double Cluster

While I was hanging around outside, I looked over at my covered-up AVX and thought about what to do with it while I worked on figuring out how to collimate the Newtonian that was on there.  I thought, "I don't have any more telescopes to put on there!"  But then I thought that I could go ahead and do an experiment I've been wanting to do -- put one of my Nikon lenses on my ZWO ASI294MC Pro, since I got the Nikon bayonet adapter a little while ago.  But then, when I was inside looking for the binoculars, I saw the wooden box that contains a Soviet 1000mm Maksutov-Cassegrain camera lens that my astro-buddy John gave me back in August.  I still need to play around with that.  Which one should I do first??   I thought about it as I headed to bed at 11 PM.

Before I went to sleep, I checked on how things went.  It failed to meridian flip for M78 -- why??  I scrolled through the logfile, and finally found it -- it says it sent the command to go to the east side of the pier (for facing west), but that the mount reported that it was already on the east side.   Until I could figure out what was up with that, I went ahead and changed the end times of the rest of my targets to be their transit time so that it  wouldn't meridian flip, and would instead just move on to the next target.  But then an idea occurred to me -- the next target would be transitting at 12:07 AM, and it was 12:05 AM, so I could watch it!  So I changed the target end time to 12:30 AM and watched it do the flip.  It failed at the first step -- actually flipping -- which means that it wasn't an issue with re-starting guiding, flipping the guide calibration, plate solving, running the focuser, etc.  So that must be what's been going on with meridian flipping lately.  Maybe TheSkyX is already sending its own flip command?  But the mount was still on the west side of the pier (I checked using the Virtual Mount render in TSX).  So there must be a comms breakdown somewhere.



Thursday, January 2, 2020

#268 - Wednesday, January 1, 2020 - Happy New Year!

Happy New Year all!

The skies weren't that great tonight, but there was a chance of them clearing out in the morning hours, so I ran anyway.  I ran my Paramount MyT with the Takahashi FSQ-106N refractor, and my color astro camera, the ZWO ASI294MC Pro.  Not much to report on tonight; I set it up and went to bed.

In the morning, I checked on how it went -- not good.  It aborted after M45, which is early in the sequence, so I didn't get any M78 frames :(  I ended up having to trash nearly all of the M45 ones anyway, and I only got to keep six -- 3x60s and 3x300s.

Hope you have 2020 telescope vision in 2020!

Image by Syaibatul Hamdi from Pixabay


Wednesday, January 1, 2020

#267 - Tuesday, December 31, 2019 - A 2017 Comet in 2019

The skies were a bit scrummy tonight, but it may be intermittently clearer, so I may as well run anyway and see what I can get.  Comet C/2017 T2 PANSTARRS was in a position in the northeast that I could reach with my Paramount, so I figured I'd see what I could get.

Earlier in the day, I finally did go ahead and swap the positions of my two mounts.  It didn't make any sense that the one that didn't handle meridian flips well, and that I wasn't currently using -- my Celestron AVX -- should sit in the spot that can see further west across the meridian and wasn't so close to the tree, while my Paramount, the far more capable mount, was in the less favorable spot.  So, yes, I'd have to re-align, but with the sky quality not being great, I didn't mind so much on losing that time.

Left: Paramount MyT mount, Takahashi FSQ-106N refractor, ZWO ASI294MC Pro camera
Right: Celestron Advanced VX mount, Vixen MyStar G-R 200SS 8-inch, f/4 Newtonian, ZWO ASI1600MM Pro camera

Over the last several nights, I've been hearing lots of scuffling sounds coming from inside my lemon tree, and I wasn't sure what type of critter it was.  But I finally got my flashlight on one -- and it was a mouse!  So that's what's been eating up all of my lemon rinds.

The clouds thinned and thickened, and a lovely crescent moon hung in the sky.  I had to restart the sequence twice myself because, despite the recovery options I have enabled to "try every 10 minutes for 10 hours," it still just gives up one the guide star is lost for like 30 seconds.  Sheesh.

Since it was New Year's Eve, I stayed up until midnight to ring in the new year, with a lap full of cat.  They were both cozily asleep, but they woke up pretty quickly once the fireworks from the various displays around the area started going off.  (We've been getting enough rain lately that the fire risk is low now, I guess).


Orion is on the left, and Nova in the middle.
Also pictured: my sweet new space-themed housecoat

On the target list were the comet, M45 Pleaides Cluster (maybe, if the small window of time between the comet and the next target was big enough), M78 nebula in Orion, Cone Nebula, Medusa Nebula, the Beehive Cluster (to fill a gap of time -- I don't typically get much good out of open clusters), and then the Whale Galaxy early in the morning.

Earlier in the day, I went outside and took a panorama of my backyard using the ultra-wide camera on my Samsung Galaxy Note 10+, which made it a lot easier in my tight backyard.  It took a couple of tries to get a decent one, and then I brought it into Photoshop to make the sky transparent, and cropped and slid the image around (you can have an image wrap around the other side of the canvas in Photoshop, thank goodness) to meet the specifications for importing it into SkySafari.  It's something I've been wanting to do for a while -- I can add this panorama in SkySafari to the sky chart so that I have a better idea of when a target is going to dip behind my lemon tree, house, etc.  I can also bring it into TheSkyX's chart.

I checked on how things went in the morning, and the sequence did complete, finally!  That was exciting.  I got several good shots of the Beehive Cluster, a fair number on the Cone Nebula, Medusa Nebula, and M78, and only two on M45 due to clouds.  Only a few of the comet shots came out as well.  However, tracking was rock-solid all night!  It was so solid that I might need to start actually dithering here soon.  I haven't needed to dither in the past because there's been enough drift and random motion between frames to not need it, but eventually I'll get my rig optimized well enough that it actually stays solidly on target.

I spent the (late) morning of the next day processing the image.  I only wound up with six 3-minute frames, so I didn't even bother trying to do the dual still-comet, still-stars image -- I just did a still-comet image.  PixInsight has a tool called CometAlignment that is really great -- you import all your frames, it time-sorts them, and then you select the comet nucleus in the first and last frames, and it figures out the position in all the frames in between.  Then I just stacked those (with no pixel rejection, otherwise the stars would mostly disappear), and tried to clean it up and make it presentable.  It was extremely noisy (using a color camera with a light of light pollution often is!), but still, it's a comet, which is always cool!

Date: 31 December 2019
Location: East Bay area, CA
Object: Comet C/2017 T2 (PANSTARRS)
Attempt: 1
Camera: ZWO ASI294MC Pro
Telescope: Takahashi FSQ-106N
Accessories: Astronomik CLS-CCD 2-inch filter
Mount: Paramount MyT
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: 6x180s (18m)
Gain/ISO: 120
Acquisition method: Sequence Generator Pro
Stacking program: PixInsight 1.8.8
Post-Processing program: PixInsight 1.8.8
Darks: 20
Biases: 0
Flats: 50