Six images bagged in one night, although a few need at least another nights worth of additional time. Big city light pollution was circumvented with an Optolong L-eNhance filter.
30 second sub-images for the DSO’s. The moon was 5 frames stacked in SharpCap 3.2. The Cone Nebula has 130 subs from last night and 63 from a previous session. I also shot M51, but it was only a few frames before twilight and was not really enough for a display image.
Sunday evening was beautiful here in Cajun Country and I did not let the night go to waste. I shot a number of things, but I went back to the Cave Nebula early on to add more data to my existing image of it.
I shot the moon next, even though the seeing was not that great. I shot 10 stills starting out slightly underexposed and progressing to over-exposed to show the dark part that was lit by Earthshine. My experiment to blend them all together was not what I had in mind in terms of look and feel. Plus, I had shot them in 8-bit mode instead of 16-bit mode in SharpCap 3.2. It was a learning experience, I guess. I’ll figure it out one day, hopefully.
I did the Monkey Head Nebula last and it hardly needed any post-processing. 50 minutes worth of data was enough to show most of it. Guiding and composition were good and the image was easy to post process. I packed it in after this, since it was nearly 2:00 am and I needed at least a few hours of sleep before work Monday morning. lol
Like before, these images were all taken from a metro area with Bortle 8 red zone light pollution levels. An Optolong L-eNhance filter was used to shoot through the muck.
Here is an interesting experiment I did in shooting short, 10-sub x 30 sec “subs-stacks” with LiveStacking in SmartCap 3.2 and stacking the stub-stacks in IRIS. I used Fitsworks first to orient the 5 min stacks taken after the meridian flip with the first batch. Final post-processing was done in PS.
I squeezed in two other shots this night – one of the moon and a test for guiding I did on Mirach. The test involved changing the PHD2 camera selection to the Ascom Toupcam driver instead of the regular version I used that gave trouble in the last session. That solved a problem with the camera dropping and losing connection.
Similar to NGC 981 above, I did twelve 10-sub stacks of Mirach for 5 minutes each for a grand total of 60 minutes of exposure:
The moon was out and after shooting NGC 891, I captured it in a .SER movie with 100 frames. I used 20 to make a still with the AutoStakkert software. Here’s the result:
Very clear conditions this night, but seeing was mediocre, with strong LP and moonlight interference. Cold for Cajun country, too… it got down to mid-to-upper 30’s. Brrr…
I am amazed at how much signal is in just 6 minutes of sub-images for this new camera, QHYCCD’s QHY183c. When you take the shot, there is really not much there without significant stretching of the image. But, since the noise is so low with this cam, it can be boosted beyond anything a DSLR image could keep up with.
Now, I did do quite a bit of noise reduction on the Veil image included here, but it had enough signal to preserve enough detail to make the image adequate for a display image. I reduced it 50% to smooth it out more, but the original size is OK, too, just quite large to be downloading on a mobile phone.
Clouds were why the session was so short. I was clouded out when it was in a prime position early on, then it went completely overcast at the end. In between, I manged to get the 6 x 1 minute subs . I gave up and tore down and stowed the rig after I couldn’t shoot anymore. Almost as soon as I had put away the last piece of gear, I went back out and it was totally clear, just like when I had started setting up. Sucker holes and I fall for them all the time. lol
I was actually just testing some tweaks to my laptop I did hoping that they would improve performance. I added memory and updated a few drivers. Stability was vastly improved, but the speed of the machine lacked. I could not do a, “live,” shot of the moon at the lower exposure needed. It would not stream with the exposure less than 350ms. Too many frames per second for it to keep up with, I guess. Means I need another field laptop. 🙁
I finally did it. I bought a new camera for imaging (and Electronically Assisted Astronomy or EAA for short) that has a cooler and is dedicated for astrophotography. It is a QHY183c from QHYCCD. It is a 20MP, Sony IMX183 BSI CMOS-based camera with electronic refrigeration to cool the CMOS chip and reduce noise.
I chose a color camera since I shoot comets and it is easier to do those with a one-shot-color (OSC) camera vs. a mono camera needing filters and a filter wheel. Plus, it was cheaper by far for the color version ($699 vs $999 or $1199 w/filter wheel) since Sony sells and produces lots more of them than the mono version of the chip. And, you don’t need a set of filters and the filter wheel, which adds to the cost considerably.
The moon image above was shot when it was still low in the sky and reddish in hue. I shot a short video of it with 61 frames. I used SharpCap 2.9, since the newer SharpCap 3.2 version did not want to work for some reason. I opened the .SER video file it produced in AutoStakkert and stacked half the frames with the default AutoStakkert settings. Some sharpening and other enhancement was done in PS.
I had a few problems with the laptop not handling the amount of data that the 20MP cam produces at it’s full resolution and highest bit-depth settings. I could get it to work in mono mode but not in color mode reliably. Later, I tried the camera with a much more robust and newer laptop and it seemed to work much better. Looks like I will need to upgrade my field laptop, which is an older Panasonic ToughBook with an i5 processor.
EAA was a blast with this camera. I was in the middle of the city and was picking up the Veil Nebula and the Horse Head Nebula with no problems. I was using a cheap UHC filter that had sharp cutoffs for H-beta/OIII and H-alpha wavelengths and that helped with all the LP. I did more EAA than trying to get data to produce finished images. I kept a few that I will tack on to the end of this post.
Images of Comets, Nebulae, Galaxies and Star Clusters