Friday, September 2, 2016

#57 - Friday, September 2, 2016 - At Last, Guiding (For Realsies This Time)

There were quite a few club members out tonight!  It’s Labor Day weekend, and lots of people brought out their RVs, campers, and tents for the weekend.  I re-aligned my telescope and re-did the polar alignment using Altair instead of Antares, and it definitely made a difference.  While Saturn was up, since the seeing was better Friday night (ClearSky even said conditions were “excellent,” which is super rare around here!), I imaged it again through the telescope with the QHY5.  I checked it with the eyepiece first – it definitely was better.  I showed some of the newer club members the view.  It was pretty good.

[I didn't quite have the planetary stacking in RegiStax with RGB data figured out yet, so I apparently never processed this data!]

I was finally able to focus the guide scope working – turns out PHD will stretch the image by like a ton (the histogram) if it doesn’t detect stars, so the noise goes away once you’re near focus.  It was just finding that point that was tough.  I made sure to mark it this time on the focuser tube.  It turned out that I was having problems focusing because I couldn’t reach the focal point with the QHY5 on the Orion ST-80.  Attached directly, it didn’t have enough out-travel (I could see the stars getting smaller, but still not near focus), and with the star diagonal, it didn’t have enough in-travel.  So I took the Barlow lens out of my Barlow and just used it as an extender tube, which put it just far enough back that I could focus without putting it too far back.  So now I just have to use that.  Rawr.  Anyway, I also made the telescope a little heavy toward the counterweight side, and once I did start guiding, it worked much better than before!  I shouted triumphantly, “At last, I’m guiding!!” 

My first target was M16, the Eagle Nebula, since longer exposure would surely get my more detail. I tried a one-minute exposure first, and my stars were still round.  Then two minutes…still steady…then 5 minutes…still circular!  However, the image was getting pretty washed out by light pollution at that point.  John Chumack recommended I use my Orion SkyGlow filter, which helped quite a bit, especially since all the interesting Milky Way stuff is in the direction of the city this time of year, the southwestish.  I still set the ISO at only 800. 
M16 Eagle Nebula, Nikon D5300 on my C11, f/6.3 focal reducer, Orion Skyglow filter
Guiding: QHY5 on my Orion ST-80
5x300s, ISO-800
[I forgot to write about this: I got a new camera, the Nikon D5300, which I used my intervalometer to control.]

Next, I tried for my first “challenge” object, the mag 11 Bubble Nebula, but it was very high altitude, and the pictures I was looking at on my tablet showed a lot of drift.  So I didn’t think my telescope could handle all the weight at that high of altitude.  It turned out that I was looking at the wrong frames – the folder I was in decided not to be date-arranged anymore.  So I went to the Helix Nebula instead, but I still couldn’t see it, even with a 1-2 minute exposure.  I’ve tried it a few times before. So I went back to the Bubble, but while trying to find it using Precise Goto, I discovered that my telescope was no longer in alignment.  It must have done the fast-slew thing from the shielded cable shorting during a slew, so I missed hearing the higher-pitched sound it makes when it does that.  So I re-aligned, and then went back to the Bubble.  I was letting PHD do its calibration run, but the star was just too far north to move much during calibration – or so I thought.  Turned out that was wrong too – PHD wasn’t talking to my mount anymore, even after re-connecting, because I couldn’t get it to calibrate for a star in the east that should have been easy.  Oh, well, tomorrow night.

It was getting late, so I decided to get some Crab Nebula images since it was rising to a reasonable altitude in the east.  I did some 3-minute exposures on it until about 4:30 AM.  By the time I hit the sack, Orion was rising and moving south, and I could see where the Orion Nebula was at.  It’s still too low to image well, so I’ll wait till October for that one, I think.  I can’t wait to do some long exposure on it!  I forgot to take darks before going to bed.  Crab Nebula turned out great though, with some darks I took the next night:
M1 Crab Nebula, Nikon D5300 on my C11, f/6.3 focal reducer, Orion Skyglow filter
Guiding: QHY5 on my Orion ST-80
10x180s, ISO-3200

Look at the filaments!!  LOOK AT THEM!!!  FILAMENTS!!

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