Sunday, April 24, 2016

#33 - Sunday, April 24, 2016

Lo and behold, we got a second clear-ish night.  There were a lot of high clouds, but I was kind of able to image some stuff.  We didn’t even check whether the gate was unlocked, since we didn’t want to have to leave early, so we set up in the new spot outside the observatory gate.  I read a little more on all-star polar alignment, and I guess I don’t have to align to Polaris first, I just have to be kinda close.  So I tried that this time, and the pictures still came out with little drift, especially because there was no wind at all.

I started with getting another 75 subs on the Black Eye Galaxy, although about 30 were accidentally 15s instead of 30s because I forgot to change the exposure time after lining up the shot.  I stacked it in various ways, combing the 15s and 30s, as well as combining with Saturday’s data.  I got some reasonable results.  The image below is only 15m15s total, shorter than another version I tried with 33m of data, but it came out clearer and with better color.
M64 Black Eye Galaxy, Nikon D3100 on my C11, f/6.3 focal reducer
19x15s & 11x30s, ISO-3200

I started imaging the Needle Galaxy too, but it was behind some high clouds.  Then Uncle Chris messaged me one of his CCD images from the night before of galaxy pair M65 and M66, and I had to try!  It took me a bit to find them both in the same frame, but I finally did, and it was in a relatively clear patch of sky.  I took 70 images, but only 24 didn’t have too much cloud or drift.  When I stacked with the flats from Saturday, it came out super weird for some reason, like there are multiple rings, but this might be due to varying light levels with the clouds and the appearance of the moon or something.  So I’ll definitely image this again on the next night, since I need more data to get some good detail on those two galaxies.
M65 & M66 (two of the Leo Triplet), Nikon D3100 on my C11, f/6.3 focal reducer
22x30s, ISO-3200
[The "multiple rings" effect came from me driving up the contrast too much, and basically you are seeing the central obstruction - aka, the secondary mirror - of my C11.]

Next post: #34 - Friday, May 6, 2016 - Outreach!

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Saturday, April 23, 2016

#32 - Saturday, April 23, 2016 - A Black Eye

Anton and I went out to the state park, and the observatory was open!  There was a Boy Scout event going on.  We got out there kind of late, though, because we got distracted playing video games before we left.  Once I finally got everything set up, I started imaging the Black Eye Galaxy.  I noticed that the collimation wasn’t that great, but didn’t have time to fix it.  People were going to leave by 11:30.  After a while, I moved to the Iris Nebula, but didn’t get very many before we had to pack up.  It was chilly, but the telescope worked well the whole evening.  The Black Eye Galaxy is interesting because of the dark dust band near the core (where it gets is name), and because the inner part of the galaxy is rotating one way, while the outer part is rotating the other.  It’s thought that it’s a result of a merger of two galaxies a long time ago. 

I also took a new set of flats – I did them outside to have a larger light source.  I just used ambient light and didn’t aim it toward the sky.  They worked out pretty decently.  I also marked on all the pieces in the optics train where they’re supposed to line up at.
M64 Black Eye Galaxy, Nikon D3100 on my C11, f/6.3 focal reducer

Thursday, April 14, 2016

#31 - Thursday, April 14th, 2016

It looked like it was going to be reasonably warm, warm enough that hopefully the telescope would work all evening, so I went out with the goal of imaging M101 and M104.  Alignment went smoothly, although there was a hiccup when the motors moved suddenly while I was starting to polar align on not-Polaris.  But its initial guesses were good for once, and I got it set up and aligned in about an hour.  I started with M101, in the north.  I noticed after a while that the stars weren’t well-formed in the subs, so I re-focused it on Dubhe and went back to M101.  I accidentally left it on 15 seconds after using that exposure time to make sure M101 was centered, so I stacked the 15 and 30 second images together.  They still didn’t turn out very well.  Then I re-collimated, and moved to M104, the Sombrero Galaxy.  Despite getting nice dots on the live view on my camera and well-aligned spikes with the Bahtinov mask, all of my M104 images were still fuzzy, and I couldn’t figure out why.  Despite the bright moon, the images came out reasonably well.  I took a new set of flats and didn’t turn the camera at all during this session, but I think the light source is just too small (the bright white spotlight on the battery) for the size of the telescope to get an evenly-white source incident on the telescope.  So soon, I’ll set it up in daylight and get new flats, and mark the alignment of all of the pieces in the optics train so I can align them the same every time to have matching flats.
M101, Nikon D3100 on my C11, f/6.3 focal reducer 
47x30s & 15s (19m30s total), ISO-3200

M104 Sombrero Galaxy, Nikon D3100 on my C11, f/6.3 focal reducer
26x30s, ISO-3200

The Sombrero Galaxy looks really cool – it’s easy to see the giant central bulge and the thick, dusty edge.  If I can get better focus, this one’s got potential.  M101 turned out dim, but I might be able to get it brighter if I image it on a moonless night and get a good set of flats.

Sunday, April 3, 2016

#30 - Sunday, April 3rd, 2016 - Finally, the mount works!

WOWEE WOW WOWWW!!  The results are AMAZING if everything actually works!!  Alignment went smoothly, for once.  Even the first guesses weren’t very far off – they were all within the finderscope.  It was in the low-50s outside, and quite windy, but the sky was clear and transparency was good, despite the wind.  I started off the evening with a set on M81, Bode’s Galaxy, and I could see the spiral structure even in the subs.  I stacked them the next morning, and besides the vignetting (I have an idea how to do flats with the German mount, since I move the camera to upright, I just haven’t tried it yet), it looks great!  This is with just 28x30 sec, ISO-3200.
M81 Bode's Galaxy, Nikon D3100 on my C11, f/6.3 focal reducer
33x30s, ISO-3200

I tried getting M81 and M82 in the same shot, but I couldn’t find M82.  Maybe I was looking in the wrong direction, because in pictures online, they look pretty close together…I’ll try again next time.

Next, I turned to M51, which was also in the north.  The subs looked promising, and when I stacked them…HOLY COW.  It came out AMAZING!!  You can see the colors, and some amazing structure!  I couldn’t believe it!  This one is just 33x30 sec, ISO-3200.
M51 Whirlpool Galaxy, Nikon D3100 on my C11, f/6.3 focal reducer
28x30s, ISO-3200

I had to throw out quite a few subs due to the wind bumping the camera mid-photo, but clearly I don’t need a zillion anymore, thanks especially to the focal reducer, probably.  I can’t wait to see what else I can do!