Monday, September 30, 2019

#220 - Sunday, September 29, 2019 - Camera Swap

I went outside in the morning to swap out cameras so that I can send my Astronomik CLS filter in to Oceanside Photo & Telescope to trade for the CCD version of the same filter.  In the meantime, I'm going to use my ZWO ASI1600MM Pro to do some hydrogen-alpha imaging!

Gear pictured:
- Mount: Celestron Advanced VX
- Telescope: Takahashi FSQ-106N, connected with clamps
- Camera: ZWO ASI1600MM Pro, attached with a T-thread connector to the Tak, with a T-thread Astronomik hydrogen-alpha filter in between
- Guide scope: Orion 50mm mini-guidescope
- Guide camera: QHY5
Also pictured is my red dot finder and the dew heater straps wrapped around both the Tak and the guidescope

My second goal for the morning was to see if my focuser was going to work while it was cooler outside.  I turned it on, and sure enough, the manual buttons on the controller worked!  For a little while, at least.  Once the sun hit it, it didn't want to work anymore, and I couldn't get it to talk to my computer either.  I will try again tonight...

My third goal was to pop open the declination axis motor housing and see what the deal was with the jumping around that occurs only when the mount is facing west in right ascension.  First, I needed to re-verify that the behavior was still happening before I took the load off the top, so I slewed westward.  So far, so good.  I made it all the way south, and it was working just fine!  Then I had it slew back to home position, and picked a star currently up in the south (although invisible in the daylight) to slew to.  It did...with no problems!  My lemon tree doesn't block the sky until about 55 degrees of altitude, so now that looking west appears to be working again for unknown reasons, I can image across the meridian and spend more time on targets.  Tonight, I will be testing out the automated meridian flip feature in Sequence Generator Pro, in addition to trying to get the focuser to work.  Lots of work to do!

After church and The Astro Imaging Channel broadcast (which I was late to, unfortunately), I went outside during twilight to do my testing.  I first tried to get the Robofocus working, but it was behaving similarly as before, where it wouldn't respond to me pressing the in/out buttons, and would beep for a long time after a button press.  I decided just to leave it on for a while and worked on setting up the automated meridian flip instead.

After re-focusing on Deneb, some clouds started rolling through, but the forecast said these would clear after 9 or so.  I got all the settings configured in both the permanent Equipment Profile Manager and the version of that I was running with my sequence, which mostly just involved ticking the box in the Telescope settings and choosing a number of minutes after transit in which to do the flip.  After getting all of this set up, however, the "time to flip" readout on the control panel window still said "N/A," and the "run" button was still grayed out.  It also didn't flip for the test start I gave it.  Finally, I restarted Sequence Generator Pro.  That worked -- it showed a time to flip, woot!

I picked another star that was about to transit, copied and pasted the coordinates from Cartes du Ciel into the target coordinates box in SGP, watched as it slewed to and centered the target, and then waited.  However, clouds kept rolling through, and PHD would abort the sequence after several attempts to re-acquire the guide star, and SGP would go into Recovery Mode, waiting 5 minutes to try again.  Finally, after several attempts, I got a break in the clouds, tracked a star a few minutes past the meridian, and then watched it flip!

The mount almost made it over to the star....dec had finished slewing, and it was going the last bit of distance in slowed for final approach...and then the dec axis started rapidly slewing back and forth again! 😭  This was especially weird because dec had finished slewing.  So I shut off the scope, manually moved it back to home position, and made sure the dec cable from the mount was nice and tight.  (Seriously why are we still using RJ-11.)  After I turned the power back on, I had it restore the last calibration (a very handy feature for power failures!), and I was going to test and see if my lining up the index marks was close enough to be able to use that alignment model or whether I would need to re-align, but the clouds had grown thick enough and over the whole sky that it was useless.  The forecast said the clouds would be clearing before 10 now, so I finally trudged inside around 8:30 PM to make some dinner.

I went back out at 9:50 PM, and it had only gotten cloudier!  However, the focuser was working -- the manual buttons, at least!  So I tried to connect on my computer again, but still "No response from RoboFocus!" even after triple-checking that I had the right COM port setting.

I decided to restart my computer, and I went ahead and ran the update that was waiting, since I had a bad feeling that if I didn't, it would run in the middle of the night and disrupt the sequence.  Unfortunately, I forgot that this particular update was a big feature update, so it was taking ages to install.  So I went back to the couch to watch more Star Trek: Deep Space Nine.  I figured if the update finished, I would just reconfigure the sequence for one-side-of-the-sky operation and I'd try again.

I checked Astropheric and my regular weather apps for an update -- it didn't look good.  My Google weather app was showing clouds until at least 1 AM now, and Astropheric was showing clouds after 2 AM.  (ClearSky hasn't been working for me in like the past two weeks, at least not the phone app).  And my tablet was still updating.  So I called it a night and went to bed.  Will try again tomorrow!

Sunday, September 29, 2019

#219 - Saturday, September 28, 2019 - The Real Party is After Dark

Last night, my neighborhood held a BBQ block party at a nearby park.  Apparently I'm already famous throughout the neighborhood, lol!  It's a very friendly neighborhood where people talk and hang out together a lot.  It's really exciting to be in such a fun neighborhood!

A little after sunset, it was dark enough for Jupiter and Saturn to pop out, so as I promised my next-door neighbors, I brought out my visual scope -- my 8-inch Celestron Schmidt-Cassegrain on a Celestron NexStar SE alt-az mount.  Jupiter and Saturn were a big hit among the kids and grown-ups alike!  I got to talk a lot of science with my neighbors, which was a lot of fun.

When just a few people were remaining, I was talking to them about the distance to objects, and how we are really looking into the past.  I was hoping to find a galaxy for them to look at, but the only ones bright enough to make it through the fog of light pollution were behind a bunch of trees.  So I went to globular cluster M13 instead, after failing to find M27 Dumbbell Nebula and M57 Ring Nebula.  The globular cluster was pretty visible with direct vision, actually, and they're pretty things to look at and wonder how so many stars can become packed into a small area -- thousands of stars inside of 145 lightyears, making it about 100 times denser than our local stellar neighborhood.  It's also amazing to think about their ages -- the cluster, and many of its stars, are 11.5 billion years old!  It is not well understood how globular clusters form at this point, but we do know that they contain some of the first stars made in the galaxy.

I wound up not having time to swap out my ZWO ASI294MC Pro for my ZWO ASI1600MM Pro, which I'm planing on using with my H-alpha filter while I send my Astronomik CLS light-pollution filter to Oceanside Photo & Telescope for a trade with the Astronomik CLS-CCD filter, which I need to block UV/IR.  My luminance filter from Astronomik does, but I don't have an easy way to incorporate it into my optical system, and I'm going to need a single filter instead of two anyway for when I eventually mount a camera lens on my 294.  It'll just make life easier.  But since I didn't get that done, I did another night of imaging with the 294 on the same sequence I've been using in the latter half of the month.  I removed the Eastern Veil Nebula as a target since I processed it earlier in the day, and since Cocoon Nebula is high enough at nightfall now to be the first target of the evening.  I will shortly be processing that one as well.  

I forgot to re-focus the telescope after messing a bit with the focus earlier in the day while I was trying to get the Robofocus to work, but I zoomed in on the stars, and they were in focus after all!  My guess was spot-on :D Crazy! So I went to bed while the sequence ran without incident.

When I copied off the images the next morning, the ones in the latter half of the night were slightly out of focus, so I wound up deleting a bunch again.  Really need to get my RoboFocus working!  I'm just not even sure where to start.

Thursday, September 26, 2019

#218 - Wednesday, September 25, 2019 - More Stuff I Need to Fix

I stayed on campus in the so-called "Panic Room" (graduate student study lounge) late working on Electricity & Magnetism homework, hoping to finish before I went home.  I did, but the last hour was painful!  I may be a part-time night owl thanks to astronomy, but my peak brain hours still end around 4 PM.

I got home around 9:15, got the scope uncovered and plugged in, and updated the transit times for all my targets in Sequence Generator Pro.  The stars in the plate solve image for the Eastern Veil Nebula looked a tad bigger than usual, so I slewed to Deneb to re-focus.  I had been contemplating re-aligning and re-polar-aligning my telescope since surely I've bumped things around with taking the cover on and off and the camera off once or twice, but nope, Deneb was very nearly dead-center on the goto.  I'll take it!  I wanted the images to download a little faster (I was using SGP to focus instead of my usual SharpCap because it was already cooling -- SharpCap downloads much faster than SGP), so I set the binning to 3x3.  However, this broke SGP, since it made the image no longer an even number of pixels in size, so I had to force-quit SGP and restart.  Luckily, I caught the camera cooler before it had warmed up too much, and I was pretty quickly back in the focusing routine (this time with just 2x2).  It was just a hair out of focus, so I adjusted it.

Bahtinov-mask-spikes, post-focus (my focuser only has one speed knob, so no fine adjustment knob, so it's a little tricky to get it perfect)

After that, I went ahead and started the sequence.  The forecast looked like it would be clear all night, woot!  I decided I wanted to see if the mount could handle 5-minute frames, even though I haven't worked on smoothing out the tracking yet, so I set M77 to have 5-minute frames this time.  Then I went to bed.  I had a dream again that it rained on my telescope!  

It was dry the next morning, of course, and I downloaded all my images while eating breakfast.  As it turned out, after the Eastern Veil Nebula and partway through the Cocoon Nebula, as everything cooled off from the unusually high heat of the day (95F in Berkeley!), the scope de-focused, and I wound up having to delete pretty much all of my images from that night!  It was probably still focused before I messed with it, but since it was hot, it didn't look that way.  I have heard that Takahashis, for all of their optical glory, have pretty bad temperature stabilization of focus. 

Cropped view of the center of the image of a single frame of M77.  This 5-minute frame shows two things, one good and one bad: the bad news is, the focus goes way out with changes in temperature.  The good news is, those blurry stars are still round, suggesting that I may still currently be able to get 5-minute subframes out of this mount!

This is increasing the urgency for me to fix the RoboFocuser on that scope.  My (extremely generous) uncle included it in the package when he sold me the scope, but I haven't really needed it yet, since my Astronomik filters are all parfocal with each other.  I used it at the Texas Star Party, but only with the manual unit since I couldn't get it to talk to my computer.  Then I learned that if you shut off the power to it, it disengages so you can manually focus without having to uninstall it.  (Very handy feature).  However, my last attempt to get it talking to my computer failed as well a few weeks ago, and I couldn't even get the manual buttons to work.  So after becoming impatient with my quantum mechanics homework on Thursday morning, I went outside to give it another go.

I uncovered the scope, plugged the focuser back into the control box, and powered it on.  I loosened the set screw on the focuser in case it did decide to work.  The red LED on the box came on, but the in and out manual buttons still didn't work.  It was hot in the sun of my backyard, so I went up onto my back porch to sit in my other folding chair while I Googled solutions.  Just as I was sitting down, the thing started emitting a high-pitched continuous tone!  So I ran over and shut it off.  When I turned it back on, the red LED wasn't coming on.  Well crap.  I didn't even do anything wrong this time, I swear!!  I posted about it on my Facebook page, and one of my good friend astro-buddies asked if it was the temperature-compensating model.  I went out and took a photo of the box and saw that it was indeed, so that got me thinking that maybe it has an auto-shutoff feature above a certain temperature or something, although it would have to have an internal sensor because I don't have a thermometer or anything plugged into it.  More research is required!

While I'm sorting that out, I also need to send my Astronomik CLS filter into OPT so I can do a trade + money for the Astronomik CLS-CCD filter.  I can't really image without the CLS filter I don't think, so what I might do instead is now that I've seen that 5-minute images can work still before I go through and fix the dec axis, I'm going to detach the ZWO ASI294MC Pro I've been running lately and attach my ZWO ASI1600MM Pro instead with my T-threaded hydrogen alpha filter that I can't fit inside my filter wheel and I'll try doing some narrowband imaging.  I got some decent narrowband shots with 5-minute subframes on the less sensitive SBIG STF-8300M I borrowed (also from my uncle), so I have reasonable confidence that H-alpha images will turn out well with the ZWO camera.  Alternatively, I still have the SBIG STF-8300M at the moment with its full complement of LRGB and narrowband filters, so I might throw that one on there instead, even though I don't like it as much.  Of course, fall is a bad time of year for narrowband in the eastern sky since we're heading into the in-between season of the summer Milky Way setting and the winter Milky Way not rising until the wee hours of the morning, but I'm sure I can scrape up some targets for the first half of the night until the wintertime nebulae rise in the early hours.  Can't waste even one of these clear, low-moon nights!

[ Update: September 28, 2019 ] 

I went ahead and processed another image today -- the Eastern Veil Nebula!
Date: 31 August 2019, 1, 3, 5, 7, 8, 18, 19, 20, 22, 23, 24, 25 September 2019
Location: East Bay area, CA
Object: NGC 6992 Eastern Veil Nebula
Attempt: 4
Camera: ZWO ASI294MC Pro
Telescope: Takahashi FSQ-106N
Accessories: Starlight Xpress filter wheel, Astronomik CLS 2-inch filter
Mount: Celestron AVX
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: 35x120s
   Total: 7h37m
Gain/ISO: 120
Acquisition method: SequenceGenerator Pro
Stacking program: PixInsight 1.8.6
Post-Processing program: PixInsight 1.8.6
Darks: 0
Biases: 100
Flats: 0
Temperature: -15C (chip)

I was so thrilled with how clear and detailed this image came out!  I even made a zoomed-in image and increased the DPI:

Besides the IR-bloated stars, I'm really excited about this image.  I'll probably re-process it once I take some time to try out some new star-reduction algorithms, but time is limited while I slog through homework!

This is a super cool object. It's a supernova remnant! It's just one side of the whole structure, known as the Cygnus Loop. A star 20 times the mass of our sun exploded about 8,000 years ago, and the material from the star has been expanding out into space ever since. Today, the area spans six times the width of the full moon from our perspective here on Earth, and is thought to be about 1,470 lightyears away. The filamentary structure is a result of us seeing this nebula edge-on; the filaments are really shock fronts. The reason we can still see this glowing gas and dust is because as it speeds through space at 105 miles per second, the shock front interacts with the interstellar medium and emits light, not only in the visible spectrum, but in radio, x-ray, UV and IR as well.

I got a chance to explore this region using a 28-inch Dobsonian reflector with an OIII filter while I was in Chile this summer, and it was so amazing! It has such rich detail and fine structure. It's also in a very star-rich part of the sky, up in the Milky Way.

Despite the light pollution, my backyard images have been easy to process.  The CLS filter really does a lot to kill the light pollution, and whatever it doesn't get, DynamicBackgroundExtraction picks up the rest.  Sometimes I've had to run DBE twice to get all the gradients, but it works wonders.  

Here's the process for this image:
- Calibrated lights with master bias using ImageCalibration
- SubframeSelector:
- Scale: 1.8 arcsec/px
- Gain: 0.059 e/ADU (haven't calculated yet for this camera)
- Highest-scoring rame: 120s_frame_35
- Debayered
- Registered with StarAlignment
- Stacked with ImageIntegration
- Combination: Average
- Normalization: Additive
- Pixel rejection: Linear fit clipping
- Applied DynamicBackgroundExtraction
- Denoised with MultiscaleLinearTransform
- Corrected color with PhotometricColorCalibration
- Applied Deconvolution with range-star mask and DynamicPSF, 20 iterations
- Stretched with HistogramTransformation
- Applied another round of DynamicBackgroundExtraction
- Adjusted with CurvesTransformation
- Grew star mask twice using MorphologicalTransformation (Morphological Selection, 70%), applied
star mask to image, then used MorphologicalTransformation to shrink stars (Morphological Selection, 30%)

[ Update: October 5, 2019 ] 

After several nights of collecting hydrogen-alpha data on the Eastern Veil Nebula, I put together the image this morning!

Date: Color: 31 August 2019, 1, 3, 5, 7, 8, 18, 19, 20, 22, 23, 24, 25 September 2019
H-alpha: 30 September, 1, 2, 3 October 2019
Location: East Bay area, CA
Object: NGC 6992 Eastern Veil Nebula
Attempt: 4
Camera: Color: ZWO ASI294MC Pro
                             Monochrome: ZWO ASI1600MM Pro
Telescope: Takahashi FSQ-106N
Accessories: Color: Starlight Xpress filter wheel, Astronomik CLS 2-inch filter
H-alpha: Astronomik H-alpha T-thread filter
Mount: Celestron AVX
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: Color: 35x120s, 129x180s
H-alpha: 13x300s
Total: 8h42m
Gain/ISO: Color: 120
H-alpha: 139
Acquisition method: SequenceGenerator Pro
Stacking program: PixInsight 1.8.6
Post-Processing program: PixInsight 1.8.6
Darks: Color: 0
H-alpha: 20
Biases: Color: 100
H-alpha: 20
Flats: 0
Temperature: -15C (chip)

I like this image much more than the first one.  I have more detail and saturation in the red areas, and I was able to pull out a bit more nebulosity.  In addition, I tried a star-reduction technique from Light Vortex Astronomy that worked great on this image.  

I'll add more details later on, gotta go make dinner and prep for tonight's imaging...

#217 - Tuesday, September 24, 2019 - Smooth Sailing

After biking home from campus after my quantum mechanics class, I did the now-usual routine: drop off stuff inside, head straight to backyard, uncover scope and plug stuff in.  I also brought my DSLR on a tripod outside again for an other attempt at the all-night timelapse.  On the hand controller for my Celestron AVX mount, I set the slew limit in RA to be -5 degrees on each side of the pier so that even if my tablet dies or crashes, it will stop tracking before it goes far enough over for my giant filter wheel to hit the tripod, or the dec axis to slip.  Now it's (mostly) foolproof!

With the now-much-faster plate solving software, the first target of the night (Eastern Veil Nebula) was slewed to and centered, and autoguiding activated, before the camera even finished cooling down to -15C.  😀 My Surface 3 tablet was charging just fine this time, so Monday night's battery drain must have just been a fluke.  I was hands-off the system by 9 PM!  So glorious.

It ran smoothly and parked itself around 5:15 AM, when the waning moon was roughly 20 degrees high.  Even the passing clouds managed to stay away from where it was pointing.  

The timelapse went well too -- check it out!

If you watch closely, you can see the streaks of the raccoons and squirrels running across my fence 😮

Tuesday, September 24, 2019

#216 - Monday, September 23, 2019 - Continuous Process Improvement

While I was procrastinating on homework, I was thinking about how dang long it takes for SequenceGenerator Pro to plate solve images so that it can center the target.  I'm losing precious imaging time!  So I decided to Google the problem and see if there were any parameters for using either the remote or local server to make it go faster.  While I was researching, I found out that one of the supported plate solve programs, called PlateSolve2, was actually free!  It's developed by Planewave.  You don't even need to install a program -- SGP ships with the program, and you just need to install the databases.  So I downloaded both (which total less than a gigabyte, much smaller than's databases), and the only parameters you have to configure are where the two databases are located (you really only need one, but having both makes it go faster) and the FOV of your telescope + camera system, in arcminutes.  Setup took minutes.

When it got dark after I had dinner, I went outside and got set up.  I also set up my DSLR on a tripod to run timelapse all night -- I thought it would be fun to watch the scope track the sky and switch between targets.  I'll post the video when I finish putting it together.  After figuring out where I wanted it and getting it focused, I got my tablet set up on the scope by about 8:45 PM.  I watched as it slewed to the Eastern Veil Nebula, and plate solved & centered the target in less than a minute!  Sooooooo much faster.  Woo hoo!!

Around 9:50 PM, I went out one more time to check how it was doing, and watch it slew to the Cocoon Nebula.  I noticed that the battery was actually discharging, even though it was plugged in -- this can happen when it's using more power than the AC adapter can provide.  It's unusual, but I figured that maybe the new adapter I got so that I could keep one with me in my backpack wasn't up to snuff.  So I swapped it out with one inside that I knew worked, and turned down the performance to better battery mode.  The plate solve went smoothly and quickly, and I headed to bed.  I was going to check on progress later in the night from my phone, but my wifi card died again, so my tablet was offline.

I got up the next morning and went outside to close it up, and saw that it was at the slew limit position!  Luckily the dec axis didn't slide out this time, and the mount had stopped tracking when it hit the 20 degrees past the meridian mark.  What I suspected happened turned out to be true -- my tablet had continued to discharge while plugged into power, and had died sometime in the night.  Exactly when, I wasn't sure.  On the hand controller, I told it to go to the home position, which is did correctly and without issue.  Then I put it into hibernate mode.

After breakfast, my tablet had recharged enough for me to turn it on, so I copied off the images to see how far it got.  It looked like it had shut down a little after 1 AM.  Darn!  Half a night gone!  I decided to bring the possibly bad charger with me to school and test out whether it did the same thing.  It turned out to be fine, so I'll just chalk it up to it being on for several days and probably having an overabundance of stuff going on in the background.  

I'll re-take the timelapse on Tuesday night, since having it stop partway through the night isn't as interesting.  

I'll also set the slew limit to only 5 degrees to prevent what didn't happen this time, but did happen last time the sequence didn't stop the mount, which was the dec axis going haywire after slipping out a bit.  So I at least won't have to worry about that if my tablet dies or crashes -- the mount will stop tracking on its own.  The only thing left is that the camera cooler will continue to run, but usually I am awake before it gets very warm out or the sun hits it, so this shouldn't be too big of a deal.

Continuing to fine-tune the process!  Now I just need to set aside some time next weekend to look into the dec axis jumping problem when it's pointing west.  I'd like to be able to do meridian flips and image for the bit of sky I have between the meridian and my lemon tree, especially now that plate solving is working so well.  And I need to be able to track longer for putting on my longer-focal-length scopes, as well as using narrowband filters, so I need to make some adjustments since I'm seeing lots of little errors in the images.  I know it can run well, since it did so good at the Texas Star Party!

Got as far as M77 before the moon came up -- here it is, center, with NGC 1055 off to the left!
And some bloaty stars, since I'm still working on acquiring the Astronomik CLS-CCD filter that blocks IR.

Next post: #217 - Tuesday, September 24, 2019 - Smooth Sailing

#215 - Sunday, September 22, 2019 - Unnoteworthy

After the TAIC broadcast, I logged off after some chit-chat with the other channel members to go get things set up outside.  I plugged my tablet back in this time, and set it to go until about 3 AM, when the moon would be about 20 degrees high.

Everything went smoothly, and I got through the Eastern Veil Nebula, Cocoon Nebula, Stephan's Quintet, and M74 before clouds rolled in and either paused the sequence from lack of guide star or clouded out the photo.  Eventually it gave up trying and homed the scope for the night.

Another successful night!  Keep the frames rollin' in while I'm snoozin'!

Well, mostly.

Sunday, September 22, 2019

#214 - Saturday, September 21, 2019 - Computer Swap

Saturday night, I gave a presentation to the Eastbay Astronomical Society (which I have recently joined now) called Origin of the Elements: The Story of Stellar Nucleosynthesis.  I gave the same talk at the 2018 Texas Star Party and at my last astronomy club, and it's a fun and information-packed talk.  It was really fun to build when I originally made it because there are a ton of unexpected surprises on how the elements are made that are non-intuitive.  For example, hydrogen fusion in stars would not be possible without quantum mechanics!  The Coulomb barrier (electric repulsion of hydrogen nuclei) is so high that in order to push two hydrogens close enough together to overcome the barrier and let the strong force take over to form the new nucleus, you need temperatures of 10 quadrillion degrees!  No star is that hot.  Instead, once the hydrogens get close to each other, the wavefunctions of the protons (because of particle-wave duality) start to overlap a tiny bit, which means there is a nonzero chance that the hydrogen nuclei can quantum-tunnel through the Coulomb barrier and thus fuse.  Super cool!

Before I left for the meeting, since it was late enough in the afternoon that my lemon tree shadowed my rig, I opened it up and got things connected.  I realized, however, that I needed my tablet for my presentation, since I use my main laptop (Cherenkov) for the slides and my tablet (Messier) for my notes.  Fortunately, on a whim, I had booted up both Cherenkov and my older laptop, Feynman, to install updates, since I hadn't used either in a little while.  So I grabbed Feynman and hooked it up to the scope.  I used it at the Texas Star Party to run my second rig, so it already had all my software and drivers installed, and I keep my Sequence Generator Pro sequences in a OneDrive folder so I can access them on any of my machines.  I tested to make sure that Feynman could indeed control the mount, and then I changed a setting for my camera so that it wouldn't start cooling until the sequence started, since it was definitely not going to be able to reach -15C when it was 25C outside.  I didn't have time to install TeamViewer, so I just had to cross my fingers that it would work.

After the meeting, I had some long conversations with other members about aspects of my talk and other cosmological questions, and I made a mental list of questions I needed to research that people brought up, like how does dark matter interact with black holes?  I also talked about astrophotography, and ended up getting home after 1 AM.  To my dismay, my telescope was in the home position, even though I set the sequence to run until 2 AM.  I went to check out why, and a plate solve had failed on the first target, and the sequence had quit!  I forgot that setting the sequence failure option of re-attempting every x minutes for x hours was not an option of the sequence, but in the options for SGP itself, so when I imported the sequence, that didn't come with it.  So I turned that option on and restarted the sequence to get just 45 minutes of data on M74 before the moon got too high.  Darn, half a night wasted!

M74, single 3-minute exposure
ZWO ASI294MC Pro, Takahashi FSQ-106N

Here's a single shot of M74.  Not much to see yet, but the power of stacking will reveal all!

#213 - Friday, September 20, 2019 - Routine

After the physics department weekly social hour, a group of us walked to Cream for some amazing ice cream sandwiches.  The rest of the group went to Taco Bell for dinner (this particular Taco Bell serves beer!), but it was already 8:30 PM, and I needed to get home so I could start up my telescope!  I would have set it to start automatically, but I didn't want it sitting open in the sun all day while I was at school.

I got home a little after 9 and got everything up and running.  I had it run until midnight, about an hour after moonrise.  Everything went smoothly.  Not much of note!

It is really cool to check on progress from my smartphone using TeamViewer.

Screenshot was taken before I changed the sequence to replace M33.

My rule on log entries stands: any night out with the telescope!  So I will continue to write up nights that go smoothly and I sleep through them.  I'll probably add some other interesting tidbits though, like setting up SGP or stuff like that.

#212 - Thursday, September 19, 2019 - New Targets

Now that I have processed my M33 image, I decided to replace it with another target or two instead.  So I spent some time that morning re-writing the sequence, and with some help from SkySafari on my phone, added in galaxy M74 and galaxy group Stephan's Quintet in place of M33.

I got home well after dark from my late-evening quantum mechanics class, and headed straight into my backyard through the gate.  I didn't have any issues booting up, and was acquiring images within 10 minutes!  Always a happy moment.

Since the moon was rising at 10:30 PM, I would only get through some M27 Dumbbell Nebula and some Eastern Veil Nebula, but that is still about 2 hours of imaging done, minus some time for slewing and centering.  Looking ahead at the forecast, there are many clear nights ahead!

I got into bed just as the scope started slewing home at 10:45 PM, and on a whim I took a look at SkySafari to see where the moon was anyway.  Of course, it was still very low on the horizon, so I decided that I could probably get away with imaging until the moon was about 15-20 degrees up.  So I added another hour to the sequence end time via TeamViewer on my cell phone controlling my tablet, and restarted the sequence.  Ultimately I ended up getting through the Cocoon Nebula and a little ways into Stephan's Quintet before shutdown.  Woo hoo!

Single frame of Stephan's Quintet, 180s exposure
ZWO ASI294MC Pro, Takahashi FSQ-106N

The little group of galaxies of Stephan's Quintet are hard to see in the subframes, but will hopefully come out better in stacking!  The bigger, brighter galaxy down and to the left of the quintet is NGC 7331, which makes a nice addition to the scene.  It lies 47 million lightyears away, in contrast to four of the five galaxies in Stephan's Quintet, which lie 280 million to 320 million lightyears away.  Sliding past NGC 7331 is the line of a dim satellite.

More to come!

[ Update: September 28, 2019 ] 

I processed the Dumbbell Nebula last weekend, but forgot to write it up here (the last night of data), so here it is!

Date: 1, 3, 5, 7, 8, 18, 19 September 2019
Location: East Bay area, CA
Object: M27 Dumbbell Nebula
Attempt: 13
Camera: ZWO ASI294MC Pro
Telescope: Takahashi FSQ-106N
Accessories: Starlight Xpress filter wheel, Astronomik CLS 2-inch filter
Mount: Celestron AVX
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: 59x180s (2h57m)
Gain/ISO: 120
Acquisition method: SequenceGenerator Pro
Stacking program: PixInsight 1.8.6
Post-Processing program: PixInsight 1.8.6
Darks: 0
Biases: 100
Flats: 0
Temperature: -15C (chip)

I couldn't get quite as much detail in the core as I was hoping to, but I'm still quite pleased with this image.  It's so light polluted, yet here it is!!

The Dumbbell Nebula is what's known as a planetary nebula -- a misnomer, since they have nothing to do with planets, but looked planet-like in 18th-century telescopes. Planetary nebulae are a late-life stage for many medium-mass stars (and in fact, our own home star will someday turn into one of these too!). These stars are shedding their outer layers of gas down to their core, which then becomes known as a white dwarf. They come in a wide variety of colors, shapes, sizes, and structures, and make fascinating targets in the telescope. The Dumbbell in particular is easy to spot in amateur scopes even under moderate light pollution. It lies about 1,227 lightyears away, and is about two lightyears wide. The red edges are the shock front of the high-speed gas interacting with the interstellar medium (it's expanding at 31 km/s!). The blue glow is from nitrogen and oxygen gas.

PixInsight process:
- Calibrated lights with master bias
- SubframeSelector
- Scale: 1.8 arcsec/px
- Gain: 0.059 e/ADU (haven't re-calculated yet for this camera)
- Highest-scoring (properly centered) subframe: frame56
- Debayered
- Registered with StarAlignment
- Stacked with ImageIntegration
- Combination: Average
- Normalization: Additive
- Pixel rejection: Linear fit clipping
- Cropped and rotated with DynamicCrop
- Applied DynamicBackgroundExtraction
- Denoised with MutliscaleLinearTransform
- Corrected color with PhotometricColorCalibration
- Applied Deconvolution, with range_mask-star_mask and PSF from DynamicPSF
- Stretched with HistogramTransformation
- Applied another DBE, this time for the blue gradient underneath M27, couple large sample points
- Tweaked with CurvesTransformation
- Used ColorSaturation to reduce pinkness in stars

Thursday, September 19, 2019

#211 - Wednesday, September 18, 2019 - Back in Action

Full-moon week is finally over, and I can start imaging again!  Not for very long yet, unfortunately, but each night I'll be able to image a little later before moonrise.  My telescope was snug as a bug under its Telegizmos 365 cover, especially with all the power cables inside of the water-resistant cable box.  Good thing too -- it rained on Sunday and Monday mornings, but the scope and cables were nice and dry!  How convenient for the first rain I've seen since I moved here a month ago to happen during full moon week :D

Last night, the moon was not up until 9:50, and since astronomical darkness started at about 8:40, I'd be able to squeeze in about an hour of imaging between two targets, M27 Dumbbell Nebula and the Eastern Veil Nebula.  Last night was trivia night with my fellow grad students, so I made a quick trip home to get the scope set up to run autonomously during trivia, since I wouldn't be back until after 10 PM.  So I got it uncovered and hooked up, which went smoothly.  However, since I had removed the camera last weekend while trying to figure out a way to attach my luminance filter to cut IR since my Astronomik CLS filter alone does not, I needed some way to verify that it was still in focus.  It was too bright for stars still at 6:30 PM while I was doing this, but I figured the camera might be able to see Jupiter.  Unfortunately, Jupiter was well west, and I haven't worked on the declination axis issue yet and really didn't want to lose alignment in case it slipped again.  So I checked SkySafari to see where Saturn was -- still east of the meridian.  It was magnitude 0.4, so I figured I might be able to see it in the camera.  So I commanded the scope to slew over to Saturn, but the dec axis slipped a little bit just before it got there!  Luckily the scope caught back up and didn't seem to lose alignment.

I turned on SharpCap and connected my ZWO ASI294MC, and sure enough, there was a little speck!  I zoomed in, and it was, indeed, Mars.  (By zooming in, I mean that I cropped the image.)

It looked pretty in-focus to me!  So I told the scope to go back to the home position, I connected SequenceGenerator Pro and PHD to all my hardware, and then I headed out the door for trivia.

When I got back around 10:20, the scope was home, and the sequence complete, since I told it to end the sequence at 10:15.  PHD went whacko for some reason near the end, which ruined the last frame on the Eastern Veil Nebula that came in, but all of the other frames looked fine.

The forecast is looking clear for the next many days, so looking forward to more data!  I've also already built my October sequence, which includes the Cocoon Nebula, Stephan's Quintet, galaxy M74, the Pleiades, the Rosette Nebula, and M42, the Great Nebula of Orion (which I'll activate later in the month when it doesn't come up so close to sunrise).  Since I completed my image of M33 from this month already, I'm going to look into swapping it out for another target today for the rest of September.  Lots of fun ahead!

Wednesday, September 11, 2019

#210 - Tuesday, September 10, 2019 - Curse You, Moon!

The moon is useful for a lot of things.  For one thing, it probably made life on Earth possible because of the tides and stuff.  It gave us something nearby to land on.  It helps us study the sun during solar eclipses.  It's helped us learn about the formation of our solar system, and our own planet.  I will even admit that it's quite beautiful to look at in the telescope, and even naked eye.

However, it is SO BRIGHT.  I have a perfectly clear night, the forecast is even calling for good seeing and transparency conditions, but I can't image because the moon is up nearly all night, and it's nearly full!  And it won't rise late enough to squeeze in any imaging between post-sunset darkness and moonrise until a week from now :(  So a week of taking darks it is!

Except, I'm having a bit of a problem with the dark frames.  Here is a single dark frame, auto-stretched:

It looks like a bright light, just off the edge of the frame.  Now, this is a 10-minute long frame (on my ZWO ASI294MC Pro), so it shines brighter above the background, but it's present in shorter-exposure frames too, just less obvious from an auto-stretch.  My first thought was that I had a light leak somewhere, so I made sure I had the cover over the scope the next time I took darks.  But the result was the same.  I debayered the image so I could see if the light had color, but it was white, which either means it's actually a white light, or it's far enough infrared to not look reddish and just appear white (much like how a remote control looks in your cell phone camera).  The extra weird part is that it's not really showing up in the light frames.  So then I thought, maybe it's a lot dimmer than it looks, and the light pollution and target are so much brighter than it that it won't show up.  However, when I calibrated some light frames with matching dark frames, the light showed up inversely as a shadow, since it had been subtracted out from what wasn't really there in the image.  Very weird.  Further testing is needed...unfortunately this camera doesn't have a physical shutter, so light could be leaking in from somewhere, but I have no idea where, except for its own red LED that is quite far away and facing the opposite direction as the camera chip.  (And I haven't seen this in my ZWO ASI1600MM Pro, which is the same body design).  More testing is needed...

Anyway, since the moon was setting around 3:15 AM, I set the telescope to start at 3 AM and just do M33, M77, and the Flaming Star Nebula before sunrise.  Worked again, no problems!  Now I have 168x3-minute frames on M33, which is 8.7 hours.  That is hands-down the most amount of data I've ever collected on a single target on the same imaging rig!  So I think I'm going to go ahead and process it during this full-moon break and see how things go.  Get excited!

#209 - Monday, September 9, 2019 - It's All Coming Together

The moon is starting to get bright, which is limiting the amount of time I can image.  It kills me that it's so clear and I can't image!!  It feels like wasted time!  My first two targets of the night, M27 Dumbbell Nebula and the Eastern Veil Nebula, are too close to the moon and would be washed out, but the Cocoon Nebula was a healthy distance away, so I just unticked those two targets so that it would start right away on the Cocoon Nebula (which was high enough to image).

When I went to connect everything, the autoguiding program PHD2 didn't want to talk to the guide camera again (even though it connected just fine), so I restarted PHD, and then it worked.  Guess I'm going to just have to do that every time.  And SequenceGenerator Pro, so that it doesn't point my telescope at the ground on the wrong side of the meridian...

I had another fully clear night ahead, and the moon would be setting around 2:30 AM, so lots of imaging to be done still, all without me having to do things :D  The cooler had brought the camera down to -15C by the time it was done slewing to the Cocoon Nebula and plate solving, and away it went!  Watching PHD run by itself is so cool...when SGP changes targets, it pauses the autoguider, slews, and starts re-capturing frames, acquires a guide star, and starts guiding, all without any of my input.  All I have to do is connect the hardware.  (And I don't even think I have to do that -- I have which profile I want to use connected to my equipment profile in SGP, and I think it will connect them for me if I let it).

I wound up staying up until about 11:30 PM catching up on blog posts and finishing the processing on the Western Veil Nebula dataset I still had leftover from the Texas Star Party.  So I remoted into my tablet using TeamViewer on my phone and watched it change targets to M33 Triangulum Galaxy.  What an age we live in :D  It failed to solve the frame, and the frame looked blank!  I flipped over to PHD to see the guide camera's view, which looked like it was partially blocked.  So I ventured outside in my PJ's and outside slippers, and saw that M33 hadn't cleared my neighbor's garage!  Transit times have gotten early enough from when I first wrote the sequence that now M33 is starting before my telescope can actually see it.  So I used an app on my phone to measure the angle above the ground that the garage cut me off at, and then looked in SkySafari to see when it would clear that altitude, and set that as the start time for the target.  It had to clear about 50 degrees in altitude, and that would happen around 12:15 AM, so I set it, and went back inside.  This is probably why the log showed it failing to plate solve a couple of times last night as well.

I was about to head to sleep when one of my cats (Orion) threw up!  He ate his crunchy food too fast after I fed them before bed, and threw it all back up.  I'll get to bed at some point...

Oh, I forgot to mention on Saturday: I finally put together something I've been wanting to do for a long time, which was a power cable box!  Previously, I made some progress on solving my cable mess by creating a cable bundle with some self-closing cable wrap, which has done a lot to make my setup better.  But my power cables were still an absolute mess, and now that my scope is going to be out in the backyard for long stretches (including through rainshowers, thanks to my Telegizmos 365 cover), I needed to do more to protect my electrical connections.  So I bought a large rainproof power cable box on Amazon, and neatly tucked my power strip, AC-to-DC converters for the mount and dew heater, tablet plug, RoboFocus plug (which currently doesn't work), and camera power plug into the box, utilizing additional velcro cable ties to keep bundles together.

At last, less mess!  Now I just need a way to attach my cable bundle to a moving part of the mount somehow so that I can prevent it from getting yanked, and I'll be good to go!  It's laying on top of the counterweight bar at the moment because otherwise gravity pulls on the cables, which will disrupt guiding and stuff like that.  Of course, doing that gives it less play, so it ends up pulling tight when I point due south and low (which none of my targets are, but during alignment it was a problem).  And sometimes it catches on the polar alignment adjustment screws as the mount swing around, so I have to guide it by hand right now (which is not conducive for future meridian flips, once I finish fixing the declination axis issues).

Bring on the clear skies!

[ Update September 12, 2019 ] 

Because I'm now in a full-moon break, I went ahead and processed M33, since I have by far the most number of frames on it.  7 hours of frames passed through my inspection and quality control in PixInsight!  That's the longest image I've ever done :O  Very exciting.  And the result was even more exciting.  Remember, now this is from Bortle 7 suburban/urban transition skies of the East Bay area, well within the light dome of San Francisco, Oakland, and all of the other 7 million people that live around the bay.  

Date: 1, 8, 9, 10 September 2019
Location: East Bay Area, CA
Object: M33 Triangulum Galaxy
Attempt: 7
Camera: ZWO ASI294MC Pro
Telescope: Takahashi FSQ-106N
Accessories: Starlight Xpress filter wheel, Astronomik CLS 2-inch filter
Mount: Celestron AVX
Guide scope: Orion 50mm mini-guider
Guide camera: QHY5
Subframes: 140x180s (7h)
Gain/ISO: 120
Acquisition method: SequenceGenerator Pro
Stacking program: PixInsight 1.8.6
Post-Processing program: PixInsight 1.8.6
Darks: 0
Biases: 81
Flats: 50
Temperature: -15C (chip)

Look at this!!!  I can't believe this came out so well from inside the city!!  This is very promising, very promising indeed.  And this is just with a light pollution filter, no narrowband or anything!  (Actually, I don't even have an IR-cut filter on here yet -- hence the weird star halos.  I'll be rectifying that this weekend).  Lots of detail came through, helped by the good tracking on my mount.  Those stars were perfect circles!  

M33, the Triangulum Galaxy, is located just 2.7 million lightyears away.  It's a member of our Local Group, the third largest after our own galaxy and the Andromeda Galaxy. It's located behind the constellation Triangulum, which is below the midway point between the W-shaped Cassiopeia and the prominent square of Pegasus. It's about 60% the size of our own Milky Way, but contains only a tenth as many stars. It has a number of fascinating structures and giant nebula that can be seen even in amateur images.

More exciting things to come!

Monday, September 9, 2019

#208 - Sunday, September 8, 2019 - Automation Nation

After Sunday night's episode of The Astro Imaging Channel (which I finally had time to join that night!), I got outside about 8:50 PM (after chit-chatting with some of the members once we were off-air).  It was clear again!  Goodness this is awesome.

Same routine -- took the cover and caps off, connected tablet, powered everything up.  I had to restart PHD again when it wouldn't get images from the guide camera.  I wonder what's up with that.  I disconnect the equipment before I unplug the USB cable!

I figured out while I was catching up on blog posts earlier in the day that the RA and dec coordinates I was grabbing from Cartes du Ciel to put into the location boxes in SequenceGenerator Pro were the "apparent" coordinates, and not the J2000 epoch coordinates.  So I went through and copied the other coordinates instead, hoping that that would fix the weird offset problem.  I found it strange that every target would be offset from actually being centered by the same amount every time if it was a mount error, and that plate solving didn't fix it.  I thought, maybe everything is working right -- but the coordinates are slightly wrong!

Then I had some other software weirdness.  I started the SequenceGenerator Pro sequence, and it started the slew to the Dumbbell Nebula, except that instead of going where it was supposed to, it started slewing west instead, and then down toward the ground!  I stopped the slew and ended the sequence, reset to home position, and tried again.  Same thing!  I was perplexed.  I double-checked the time, date, and coordinates on the telescope and my computer, and they were correct.  I used the scope's hand controller to slew to the Dumbbell, and that worked just fine.  So what was wrong with SGP?  Finally, I disconnected everything in SGP and restarted the program.  When it slewed to the Dumbbell this time, it did it correctly.  Phew!  But also annoying.  The good news is, putting in the J2000 coordinates seemed to have worked -- M27 was smack in the middle of the screen.  Yay!  One more problem solved.

Another thing I did earlier in the day was to investigate how to let the sequence try again if something failed.  The log kept saying "no recovery options selected," so I decided to go find these recovery options.  It didn't take too long to find them, and you can set it to try the sequence again where it left off every X minutes for X minutes.  So I set it to do every 10 minutes for 3 hours.  This way if clouds are passing through, or the plate solve fails, it will try again.  But if the clouds stick around, it will eventually give up.  I may modify this, but we'll see!  Another problem solved.  Getting closer to being able to sleep easy while the sequence is running.

The moon is heading toward full, so I'm going to have to start imaging later and later, then take off a few nights around full moon, and then end earlier and earlier as the moon waxes.  But with it all automated, I can have it start or end at whatever time of the night, and I don't have to do anything.  So glorious!  I'm going to get a lot of imaging done.  Limited range of targets, but a south view still gives me plenty!

In the morning, I checked on how everything went -- it did fail to plate solve a few times, but with the recovery options on, it tried again, and eventually succeeded.  I had a full night of images!

Here's a single frame of M33, the Triangulum Galaxy.

M33 Triangulum Galaxy, single 3-minute frame
Camera: ZWO ASI294MC Pro, Astronomik CLS filter; telescope: Takahashi FSQ-106N; mount: Celestron AVX
(click here for the final image!)

The light pollution is definitely going to be a challenge, but we'll see what I can do with it!  Also, during the TAIC presentation, after much talk about the Advanced Imaging Conference, I went ahead and registered!  San Jose is only about an hour from me in low traffic -- way closer than the plane flight it would have been before!  I'll probably take public transit out there, or maybe stay down there for the weekend, I'm not sure yet.  Really excited to learn some new techniques and talk to other astrophotographers!

#207 - Saturday, September 7, 2019 - Chugging Along

The physics department graduate students held our "post-prelims party" on Saturday night, which was some good fun.  We had a good turnout, and the view from the back deck of the student's house who was hosting was gorgeous!  Wish I could set my telescope up on a deck like that!  I heard he had a great view, and I almost brought my DSLR on a tripod to do timelapse...almost.  ;)

Before I went, though, I got my telescope queued up to run without me, since it promised to be clear.  Shortly after sunset, before I had any stars, I pulled off the cover and the caps, and plugged in my tablet and got everything connected.  PHD connected to my guide camera (red hockey puck QHY5), but it couldn't grab any frames, so I rebooted PHD, and then it was happy.

Since my current last target, galaxy M77, transits at 4:44 AM now, that leaves another half an hour until the first light of dawn begins to appear at 5:13 AM, according to my handy "Calendar - Sun & Moon" app.  So I decided to add another target, since M77 will transit earlier and earlier, and sunrise will come later and later anyway.  After scrolling through SkySafari's "Best Deep Sky Objects" list and gating out targets that were too low or not in my open sky view, I settled on the Flaming Star Nebula.  I've tried it once before, way back in March 2017 on my astronomy club's Vixen 140mm neo-achromat, but I only got a couple of subframes that night and had other issues.  Time to try again!

The half-moon was just east of the meridian, so before I finished getting ready to head to the party, I slewed to it to grab some video.  I grabbed two -- one with the Astronomik CLS filter I've been using (it's currently sitting where my luminance filter previously sat, so I don't currently have a clear filter loaded), and the other with my infrared filter.  IR filters can help because infrared light isn't as disturbed by the atmosphere, generally speaking -- not at the super-near IR wavelengths, anyway.  I haven't processed the video yet (RegiStax is having issues with my one-shot color cameras), but here's a single frame!

I cropped the frame size in SharpCap so that it would download faster, and got a nice 25 fps at this size on my ZWO ASI294MC, which is USB 3.0.  The moon does have a slight reddish tint -- that IR filter dips a tiny bit into the red, so if I hold it up to an incandescent lightbulb, I can see a little bit of very red light through it.  It's actually a Johnson-Cousins photometric filter, part of a photometric filter set I got from one of my previous astronomy club members.  The atmosphere was pretty shimmery, so we'll see how it turns out!

While at the party, I was telling some people about how my telescope was running autonomously in my backyard! :D  The idea also struck me -- I wonder if TeamViewer has a smartphone app?  So I went to the app store (I'm Android), and sure enough, they do!  I had recently installed TeamViewer on my tablet so that I could watch progress from inside (I'm prepping for winter here) after failing to get the new Windows Remote Desktop app to install on my desktop, since my Microsoft Store (and the Feedback Hub) haven't worked for months.  My tablet is also running Windows 10 Home edition instead of Pro, which I've read can't do remote desktop (although it might be accessible by it, maybe it just can't initiate a connection, which would be fine).  Anyway, TeamViewer is free for personal use, and it's been working great.

So the next day, I tested out the smartphone app -- and it totally worked!  Now I can check on the progress of my setup anytime, anywhere (especially my bed)!  And not only that, I can even control the computer from it.  Very exciting :D

Looking at my tablet screen from my smartphone!  Watching it slew to my next target and center it.

The sequence ended up ending early when it couldn't plate solve for M33's position -- perhaps some clouds rolled in, I have no idea.  Or maybe the plate solver just failed.  I need to investigate if there's a way to let the sequence try again after some time, or wait for the next target, or something.

So far, so good!  Making progress toward automation!