#227 - Sunday, October 6, 2019 - Outreach Again!

Between my trip to Chile and my move to California, I haven't had a lot of time for outreach.  I finally go to do a little at Sunday night's Members-Only Viewing Night of the Eastbay Astronomical Society.  The EAS is based out of the Chabot Science Center, and they have some pretty incredible telescopes on a really nice deck above the main building.  One of them is a 20" Warner & Swasey refractor, through which I got to enjoy some gorgeous views that evening.

In a dome to the left of the 20-inch, named "Rachel," is "Leah," an historic 8-inch Clark refractor made in 1883.  

In a roll-off shed to the right of Rachel is "Nellie," a glorious 36" Schmidt-Cassegrain (I think) reflector that is used for NEO (near-Earth object) research.  

With a good ol' Telrad on top. :D

I brought along my humble 8-inch Schmidt-Cassegrain scope on its Celestron NexStar SE mount and got it set up on the patio.  There were a few families present for telescope viewing that night, and I showed off the moon and Saturn to them, which is always a delight, for both the kids and the adults!  Seeing those craters up close is a totally different experience.  And actually seeing Saturn's rings is a surprise to many people!  Despite lots of thin passing clouds, the atmospheric seeing conditions were astounding that night.  Like rock-solid steady.  It was amazing!  I did bring my ZWO color camera and grabbed some video in between the clouds, but I haven't processed it yet (RegiStax has been having trouble with my color videos anyway -- may need to give AutoStakkert a try).  

Through the 20-inch refractor, I had the pleasure of enjoying a few targets that evening.  First was M57, the Ring Nebula, which despite the moon, had great contrast against the background!  I couldn't resolve the central star, but it was gorgeous to look at nonetheless.  Next, I got to see dazzling globular cluster M15, which through a 20" aperture boasted hundreds of individually-resolvable stars that glittered in the sky.  Finally, we went over to a type of star that I have not really observed much of before: a carbon star, in particular, T Lyrae.  Carbon stars are interesting because they're in the asymptotic giant branch (near the end of red giant stars' lives), and they've largely run out of hydrogen to fuse and are instead fusing helium through the triple-alpha process, which produces carbon.  Oftentimes, these stars have hydrogen-burning shells, but every 10,000-100,000 years or so, they will develop a helium-burning shell instead, which causes hydrogen fusion to stop for a period of time.  This causes material from the core to rise up (including lots of carbon), and the star's luminosity increases.  The rising-up of carbon makes the star expand, which makes it cool enough that helium can no longer fuse, and hydrogen fusion restarts.  These are known as helium flashes.  After many of these, enough mass has been lost that the former red giant becomes a white dwarf inside a planetary nebula.  The carbon that rises up to the upper part of the star gives these stars a strikingly red appearance.  It was really neat to see in the eyepiece!

The EAS & Chabot volunteers closed up the domes around 9:45 as the clouds grew thicker.  It was a fun evening, and I was sad to go!  Of course, I did need to get to bed for my 9 AM class on Monday morning.

Next post: #228 - Monday, October 7, 2019 - Focus Pocus

Previous post: #226 - Saturday, October 5, 2019 - Target of Opportunity

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#226 - Saturday, October 5, 2019 - Target of Opportunity

I was scrolling through Facebook when I came across a gorgeous image of comet C/2018 W2 (Africano) in the ZWO user's group.  I went and checked its current location and brightness in SkySafari, and it was in the southeastern sky in the first half of the evening, shining at magnitude +10!  Within reach from my backyard.  Of course, I currently had my ZWO ASI1600MM Pro monochrome camera attached to my scope with a hydrogen-alpha filter, which wouldn't do for a comet.  So I opened up my October color camera sequence in Sequence Generator Pro and modified it to add the comet, as well as populate the transit times, when I would need to move to the next target.

I don't have my new Astronomik CLS-CCD filter yet (the CLS light pollution filter, but that also blocks IR and UV), but I've already sent off my CLS filter, so I had to use just a luminance filter instead (blocks IR and UV, but no light pollution filtering).  I wasn't sure what I would be able to get, but at the very least, I'll be able to do a neat comparison of some other targets I had on the sequence with and without the light pollution filter to show how big of a difference in makes.

When I was adding the comet to the sequence, I obviously needed a set of coordinates that would have the comet near them for the whole two-ish hours I was going to image it.  The comet's coordinates would continually change as it moved across the sky, and I don't think SGP does comet tracking.  So again I went into SkySafari and found the comet, selected a nearby star to center on, and watched how it moved across the sky during the time I was going to image it.  Then I selected a star to center on that would have the comet in a reasonable part of the frame for the whole time, and used the coordinates of that star to feed into SGP to slew to and center on.

It wouldn't be high enough to image until about 9:15 PM, I went outside around 8:45 to get set up.  I swapped out my 1600 for my 294 with the filter wheel and the L filter loaded inside.  Then I fired everything up and slewed to star Enif for focusing.  However, the declination axis did the jumpy thing!  It's the first time I've seen it do that facing east and not west.  So I rebooted, loaded last alignment, and snugged the dec cables deeper into their ports, which I was beginning to suspect was the cause of the problem.  I slewed to Enif again, but  I didn't see it in the FOV in SGP, so I looked at the finderscope, and it was way off!  I will note, however, that I could see some other stars that looked very much in focus.  So fun fact -- my filter wheel is the same width as my 21mm spacer + h-alpha filter!  That makes life a little easier for camera-swapping!

So I needed to re-align, and started that process.  However, when I slewed to Alpheratz as the first star, it wasn't in the FOV when I put the red dot finder on it.  I wondered if it had been jostled or something from my scope cover.  I looked at the mounting bracket, and yup, it had been turned a bit, and the bolt was a little loose.  So I rotated back to center and tightened the bolt.  I needed to re-align the finderscope though because no way was I going to be able to eyeball it exactly as I had it before, so I slewed over to a tree to line it up.  Unfortunately, I wasn't able to focus on the tree after all, but the moon was still just ahead of my lemon tree, so I slewed over there and used it to adjust the finderscope.  Finally, I re-started the alignment process!

At last, I started getting comet images at about 9:50 PM.  If I adjusted the auto-stretch in SGP a bit, I could just see the nucleus!

I set it to take 2-minute subframes, and 3-minute subframes for all the rest of my targets.  Then I went off to bed.

All of the early-morning images were out of focus from temperature changes.  I posted on Cloudy Nights today about getting advice on what's wrong with my Robofocus -- no responses yet, but hopefully someone out there has an answer!  The light pollution was pretty rough.  We'll see how the comet image turns out!

[ Update: October 12, 2019 ] 

I finished processing this image on Monday the 7th, but haven't had time to write it up yet.

I first attempted to do a still-comet, still-stars double-stack, a la this PixInsight tutorial, but despite my efforts, the comet was too close to the noise in intensity to not have the subtracted-out streaked stars still appear.

So instead, I decided just to do a still-comet, moving-stars image, which is cool in its own right because it shows in a neat way how much the comet moves against the background of stars.  

Date: 5 October 2019

Location: East Bay area, CA

Object: Comet C/2018 W2 (Africano)

Attempt: 1

Camera: ZWO ASI294MC Pro

Telescope: Takahashi FSQ-106N

Accessories: Starlight Xpress filter wheel, Astronomik L Type 2c 2-inch filter

Mount: Celestron AVX

Guide scope: Orion 50mm mini-guider

Guide camera: QHY5

Subframes: 31x120s (1h2m)

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)

Previously, I used DeepSkyStacker's comet stacking tool to process my last comet image, although I did use PixInsight to make the video.  This time I processed in PixInsight alone.  In DSS, you have to select the comet nucleus in every frame.  In PI, you only have to select it in the first and last frames, and it figures it out from there!  

After calibrating the frames with the master bias (no darks because the amp glow is reallllly bad in them), scoring with SubframeSelector, and debayering the color frames to actually have color, I aligned the frames on the comet using the CometAlignment process.  Then I stacked those frames with no pixel rejection in ImageIntegration, since it would have largely rejected the stars (which is more or less what you do to get rid of the stars for the "starless" comet image if you're going for a steady-stars, steady-comet composite image).  Luckily, I only had one satellite pass, and it was a slow-tumbling rocket body that was quite dim.  In addition, my CMOS cameras have pretty much no hot pixels, or at least not any that you really notice.  

After that, I applied DynamicBackgroundExtraction three times back-to-back, since the background gradient was all crazy because of aligning on the comet instead of the stars.  I stretched the image, tweaked with CurvesTransformation, and voila!  Comet epicness.  Since I only did 2-minute frames to avoid having the comet moving noticeably during a frame, I didn't get much of the tail, but you can tell it's a comet nonetheless!  And I did get some of that awesome blue-green color.  

Here's the workflow:

- Calibrated lights with master bias

- SubframeSelector:

- Scale: 1.8 arcsec/px

- Gain: 0.111 e/ADU

- Highest-scoring frame: frame16 (92.868)

- Debayered

- Registered with StarAlignment

- Aligned on the comet using CometAlignment

- Stacked "starless" image using ImageIntegration

- Combination: Average

- Normalization: Additive

- Pixel rejection: Winsorized sigma clipping

- Sigma low: 2.0

- Sigma high: 0.4

- Aligned on stars using CometAlignment, and subtracted starless comet integration

- Cropped with DynamicCrop

- Applied DBE to starless image for gradients and background

- Applied high-density DBE to starless image to remove traces of background stars

- Combined starless and cometless images using PixelMath

- Applied DBE to combo

- Denoised with MultiscaleLinearTransform

- Cropped again with DynamicCrop

- ...looks terrible

2:

- Stacked comet-aligned images, no pixel rejection

- Cropped with DynamicCrop

- Applied DBE 3x

- Stretched with HistogramTransformation

- Adjusted with CurvesTransformation

Letting the stars streak gives it a really cool effect that makes it feel like the comet is flying through space.  Well, it is!  It was moving about 34 km/s relative to the sun on the night I imaged it!

Next post: #227 - Sunday, October 6, 2019 - Outreach Again!

Previous post: #225 - Friday, October 4, 2019 - Odd Happenings

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#225 - Friday, October 4, 2019 - Odd Happenings

Yet another clear night in the East Bay...I was worried before I moved here about how often it would be foggy, but the fog pretty much stays over San Francisco, and doesn't often make it over to the Berkeley area, at least this time of year.  We'll see how the winter goes.  But for now, the forecast is showing tons of clear skies, and I'm filling up my hard drives!

The Robofocus is a bit of a mystery.  It worked just fine when my uncle had it, but I couldn't get it to talk to my computer at the Texas Star Party (although the manual buttons worked there).  Now, (sometimes) I can hear and feel it engaging the magnetic brake, but the buttons won't actually turn it -- the LED light is on, but about 5-10 seconds after either a short or long button push, it emits a loud, steady tone for 10-20 seconds.  There is nothing in the manual that mentions this behavior (I've read it twice), and nobody online, at least that I've found, has mentioned it either.  Might be time for an email to Technical Innovations.  Even the few times that the buttons have turned the focuser, it still won't talk to the computer (and I've triple-checked the COM port number, and have plugged it in by itself too).  I've even re-installed the software.  *sigh*

The reason I bring this up is because I had to toss out a lot of images from last night for being out of focus, at both the beginning and end of the night.  The ones in the middle were okay, although not perfect.  Except for several of the M77 ones, which were rockin'!  I was able to resolve some detail!  That detail will get more clear once I stack and beat down the noise.

Zoomed-in image of galaxy M77, 5-minutes in H-alpha light, ZWO ASI1600MM Pro, Takahashi FSQ-106N

Something happened this morning though that I can't quite piece together.  The Rosette Nebula only got an image about every 25 minutes, as did the Orion Nebula, and PHD was going crazy before the sequence ended.

SequenceGenerator Pro was showing some errors in settling the auto-guider, so I figured maybe there were clouds.  The couple images I did get didn't show evidence of clouds, however.  Although, I suppose that maybe if they were patchy clouds, it caught those images in the clear moments.  But then the auto-guiding would have to fail in-between frames only, which is unlikely, since I don't have SGP set to abort or delete a frame if the autoguider fails, it just won't start the next one if it does, and I would have seen clouds in those.  Weird.  Also, to add to the mystery, the mount was showing a "Slew Limit Warn" message on the screen.  I currently have the slew limit set to 5 degrees past the meridian in RA.  M42 didn't cross the meridian until 10 minutes after my sequence ended though, so that wouldn't make sense.  I'll have to go through and double-check the timing logic on everything.

Next post: #226 - Saturday, October 5, 2019 - Target of Opportunity

Previous post: #223 & #224 - Wed & Thu, October 2-3, 2019 - Another Sleepful Night

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#223 & #224 - Wed & Thu, October 2-3, 2019 - Another Sleepful Night

I'm combining these two nights because the same thing happened during both of them: everything was great!  Even though my Robofocus still isn't working, I've found a focus point that at least at current temperature swings has me very close to focus all night long, which just slight shifts on either side.  Over those two nights, I collected:

11 images Cocoon Nebula
46 images M33 Triangulum Galaxy
43 images M77 Cetus A galaxy
29 images Rosette Nebula
28 images M42 Orion Nebula

All are 5-minute hydrogen-alpha filter images on my ZWO ASI1600MM Pro on my Takahashi FSQ-106N with my Celestron AVX mount.  Except for M42, which is a repeating series of 15s, 60s, and 5-minute images so that I can properly expose the wide range of brightnesses, from the very bright core to the dim outer reaches.

You might ask yourself, "Why take H-alpha images of galaxies? I thought only nebulae had much H-alpha."  While this is largely true, there are quite a few galaxies that are undergoing furious rates of star-forming activity, known as starburst galaxies.  These subsequently have a lot of dense regions of H-alpha.  Other galaxies, like M77, have large nebulous and dusty regions without necessarily being starburst galaxies.  M33 is very close to us, and we can see several of its normal nebulae.  I wonder if sky-watchers in M33 enjoy large beautiful nebulae in our galaxy?

M77 is very interesting in radio light too, being a very strong radio emitter known as a Seyfert galaxy.  The radio source, discovered in 1952 and designated Cetus A, turned out to be a point-like source after investigation in optical wavelengths by the Hubble Space Telescope and the Keck 10-meter telescope, only about 12 lightyears across.  Since then, it has been determined that the source is a supermassive black hole at M77's core, weighing in at 10 million times the mass of the sun.  Surrounding the core are dense regions of star-forming activity, which I'm hoping to capture nicely in H-alpha.

Single, 3-minute color frame from my ZWO ASI294MC Pro, zoomed in

It's a little small to image properly using my Takahashi, but it has a rather extended disk, and there's a few other galaxies in the area, so we'll see how it turns out!  It will be in a good area of the sky to image through mid-December, however, so I'm probably going to collect a fair bit more data before I process it.  I already have 91 color images and 79 H-alpha images, but when you're trying peer through thick light pollution, the more the merrier!  Plus then I can do a more severe cut on image quality and star FWHM (so I can gate out the ones that were a little more out-of-focus) and pick the best subframes from among many.

Next post: #225 - Friday, October 4, 2019 - Odd Happenings

Previous post: #222 - Tuesday, October 1, 2019 - Well, It Could've Been Worse

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#222 - Tuesday, October 1, 2019 - Well, It Could've Been Worse

Tuesday morning, I peaked out my back door to check that my scope was in the home position as soon as I got out of bed, as has become part of my morning routine.  However, rather than being in the home position, it decided it wanted to check out the southern hemisphere!

It wasn't slewing, which was good (I hoped).  I looked at Sequence Generator Pro, and it was showing complaints of being unable to find guide stars around 7 AM...but it should have stopped at 5:30!  Why didn't it stop?

I told the mount to go to the home position, and while RA went to its normal spot, dec, didn't.

Upon further investigation of Sequence Generator Pro (once I brought it back inside where it was warmer!), I saw that while I had set a sequence end time for my new hydrogen-alpha sequence, I forgot to actually tick the box to enable it!  I also saw that I had Orion Nebula images, which was my last target of the night.  So putting the pieces together, here's what I think happened: It was tracking M42 (Orion Nebula), and when it crossed the meridian at 6 AM, the dec axis must have done its whacko thing of zipping back and forth very quickly.  It must have stopped doing that at some point, since it wasn't still doing it when I woke up.  When that happens, those movements aren't tracked by the encoder, so it loses its position, which would explain why the dec axis didn't actually go to the correct home position.

I got some hilarious comments on Instagram:
- "This post gives me anxiety!"
- "Clearly this is just your unannounced neutrino detector continuing to track the target"
- "It misses Atacama and is trying to polar align itself?"
- "Still trying for the southern hemisphere targets I see"
And Facebook:
- "Your scope found a new star"
- "Cosmic Ray Mode?"

Fortunately, nothing appears to have been harmed!  I decided to turn off meridian flipping until I further diagnose the dec axis issue.  If something breaks and the scope keeps tracking a target to the meridian, then it will just stop at the RA limit I set on the hand controller of 5 degrees past the meridian and stay there.  That's a fine state to end up in, and should prevent things from breaking.

And, and, and, the images are legit!!

5-minute single frame on M42 Orion Nebula (I'm also taking 60s and 15s frames to capture the core).  H-alpha filter, ZWO ASI1600MM Pro, Takahashi FSQ-106N.

5-minute single frame on the Rosette Nebula.  Didn't quite have the correct coordinates...

The ones in the second half of the night were just a hair out of focus...really need to get my stupid Robofocuser to work.

The Rosette Nebula ended up not quite in the center of the frame.  It's a tough one to get centered coordinates for because the nebula itself doesn't really have a catalog number, just the various star clusters and sections of the nebula discovered by various people like Herschel.  To remedy this, I went into Cartes du Ciel, picked a star that was close to the middle of the "donut hole" of the center of the nebula, and used the coordinates for that to feed into SGP.

After attempting to get some homework done (and failing to concentrate, I finally just made some lunch, and then headed onto campus for quantum mechanics discussion session, and then more group homework time in the "panic room," aka the graduate student lounge.  

After I got home from my late-evening quantum mechanics class, I set up my scope after re-checking the forecast.  Since the dec axis got lost, I was curious to see how close it would be if I just lined the index markings back up and re-loaded the previous alignment model.  I slewed to a star in the east, and it wasn't too bad!  The star was at least in my camera's FOV.  I did re-add that and another alignment star just to firm things up a bit so that the centering process wouldn't take too long.  

I tried again to get my Robofocus to work, and it did work using the manual buttons!  I noticed through that they were backwards -- the out button pulled the drawtube in, and the in button pushed it out.  The manual says you can have it reverse by turning it off, and then back on while holding the "out" button.  I did this, but then it went back to the not-working mode, where I push one of the manual direction buttons, it doesn't move, and then emits a long and loud beep.  Sigh.  This stupid thing will never work.  I Googled some solutions earlier in the day, but nobody else in the world seems to have ever had this problem, or at least they haven't posted about it online anywhere.  I've disconnected and reconnected power, the serial cable going to the motor, and the computer cable, but to no avail.  Finally, I gave up and just focused manually.

My tablet wifi card quit working again even after re-booting, so I couldn't check on progress using TeamViewer.  Oh well.  I went out and checked on it again one more time before bed, and everything looked good.

The sequence ended as it was supposed to, and parked the scope.  Woot!  And my Rosette Nebula was properly centered this time with the different set of coordinates.

Super cannot wait to stack these!!!

Next post: #223 & #224 - Wed & Thu, October 2-3, 2019 - Another Sleepful Night

Previous post: #221 - Monday, September 30, 2019 - I'm Still Up Late Sometimes!

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#221 - Monday, September 30, 2019 - I'm Still Up Late Sometimes!

After ordering pizza for dinner (what, I'm tired already!), I went out around 8 PM to get my setup back up to speed after Sunday night's dec axis shenanigans.  I re-aligned the mount with two alignment stars and two calibration stars, and focused using Deneb and my Bahtinov mask, since the  RoboFocuser still didn't want to talk to my computer.  The dec axis didn't go crazy on the stars in the west, even pretty far south, woo hoo!

Picture was actually from Sunday night, but same diff.

I've got my ZWO ASI1600MM Pro attached to my Takahashi FSQ-106N on my Celestron AVX mount, with an Astronomik hydrogen-alpha narrowband filter in place.  Narrowband filters only pass a small band of light through at specific, common emissions from deep sky objects; H-alpha is an emission from hydrogen at 656.3 nm, or a deep red.  Because it selects only a few nm-wide swath of the light spectrum, it blocks all other light, including city lights!  So the contrast is a lot better, even in heavy light pollution.

Now it was time to try again with the automated meridian flip, since I didn't have clouds this time.  (Well, a few threatened in the south, but never really came in).  I picked a star just east of the meridian and told the mount to slew there, but it was still going to the west!  So I double-checked the meridian setting on the mount, and sure enough, it was on "favor west."  So I switched it to "favor east" and tried again.  I made it over to the test star, waited 4 minutes, aaaaand...success!

Super exciting!  PHD started doing some weird stuff, but I needed to re-calibrate anyway after accidentally knocking the guide scope loose over the weekend and having to re-tighten it almost certainly at a different angle and pointing position than I had it before.  

After re-calibration of PHD, I started the rest of the sequence, beginning with the Eastern Veil Nebula, and I waited for the first 5-minute frame to download.  When it came in...Wowee!! My jaw dropped!

So gorgeous!!  I'm really excited about this!  And my stars looked great when I zoomed in!

Now that that was rolling along well, I went inside for a while, and then came back out while it was performing the meridian flip on the Eastern Veil.  I watched it slew, plate solve, and start imaging, and all went great!  Very exciting.  

Then, as I was watching the guiding in PHD, the dec axis started to drift again like it had for the test star, and it just kept going and going!  On my Celestron mounts, usually I have to let guiding sort of settle for a few minutes to take up the backlash.  This time though, it looked fine for about 30 seconds or so, and then go way off and not come back.

And by a lot, I mean a lot.

I went over to PHD to make sure that the calibration actually flipped, but I wasn't sure how to tell.  So I flipped it myself, and watched the graph for a while.  It would be fine after re-acquiring the guide star, and then it would run away again.  This went on a few times, same pattern, so it obviously wasn't just a sticky spot or taking up the backlash.  

Finally, I gave up on imaging west of the meridian, and I went inside and remoted into my tablet while I modified the sequence to just do the eastern sky once again.  It was getting chilly outside!  But I've also finally achieved another astrophotography goal -- remote control!

I'm pretty excited to get some images of the Rosette Nebula and the Orion Nebula in H-alpha!  I haven't taken a new Rosette Nebula image since my first super epic one back in February 2017.

By the time I got the sequence re-configured, and after Sequence Generator Pro had some issues re-starting guiding in PHD, the next target after the Eastern Veil Nebula, the Cocoon Nebula, was close to crossing itself, so I only got two frames in.  Then it slewed to galaxy M77, Cetus A, but I realized as it was slewing that M77 was a lot lower than I had realized!  So I needed to fill in the gap with another target until M77 was higher.  Time for a good-ol' target hunt!

I scrolled through SkySafari on my phone, but couldn't come up with much that wasn't either too small, didn't glow in hydrogen alpha, or outside the visible range of my scope between my house, my neighbor's garage, my plum tree, and my lemon tree.  I can get some of the high-altitude north above my trees and house, though, so I thought I'd try for the Bubble Nebula, which would be great in H-alpha.  

Images started coming in, but the stars looked weird.  At first, I couldn't quite put my finger on why it looked familiar, but I went outside to see if something was up.  When I got down to the scope, I heard a rustling sound on the ground next to my neighbor's garage.  I turned on my headlamp to white light, thinking it was a raccoon, and saw it -- nope nope nope, it was a skunk!  So I hurried back inside quietly and quickly as I could!  I waited a few minutes, and then stopped the sequence and turned on my backyard lights.  I didn't see him.  So I went outside and shined my headlamp into the darker areas -- no sign.  Phew!  That was close!

I turned my attention back to my scope, and saw that unfortunately, the Bubble Nebula was indeed behind my plum tree.  The weird star shapes must have been diffraction through the branches.  

Zoomed-in view

Soooooo I'd have to choose a different target.  It was already 11 PM!  :(

After scouring the target lists, I finally just settled on M33.  I've already processed that image, but I could add some H-alpha to it to bring out the star-forming regions (of which M33 has many!)  M33 wasn't going to transit until 2 AM, so I wouldn't have to lose any imaging time while waiting for M77 to be high enough.  

I watched M33 plate solve and take the first frame.  I zoomed in to look at the stars, and it was slightly out of focus!  Rawr, I really need to get the RoboFocus working.  The Tak really is sensitive to temperature changes!  So I threw my sweater on and went back outside to adjust the focus on nearby star Mirach, which I queued the mount to slew to using Cartes du Ciel from inside the house on the remote desktop.  

I waited for the next M33 frame to come in after slewing back to it and re-centering it, and it looked much better.

It doesn't look like much now, but it will...

Finally, after midnight, I went to bed.  Hopefully things would run smoothly the rest of the night!

See, even with this automation thing going, I'm still up late sometimes, trying to get things to work!

Next post: #222 - Tuesday, October 1, 2019 - Well, It Could've Been Worse

Previous post: #220 - Sunday, September 29, 2019 - Camera Swap

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#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 RA...it 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!

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