M106 3/29/20 Stakker-Lite + In-Camera NR

[Hankmeister3]

Local and on-line forecast for 3/29/20: Skies clearing by 5:00 pm, clear skies throughout the evening, winds decreasing to 14 mph by 9:00. Quarter moon.
Reality: Skies clearing by 5:00 pm, partly cloudy by 8:30, winds still stable at 25 mph by teardown time and totally cloudy by 10:30. Quarter moon was a big factor throughout the shortened session.

I mean, what more could an APer ask for? Heh!

Fortunately I was able to locate behind a 15 foot tall berm at my sportsman's club which reduced swirling wind effects to 4 to 5 mph. However some gusts reached 10 mph despite the protection. I was too lazy to erect my new windbreak and I thought the berm would suffice with declining winds. Of course, winds never declined.

After dodging clouds for the last two hours, I gave up. However, I was able to get several different strings of lights of six different DSOs. Once again I wanted to focus on getting galactic images after I verified my Orion 6-inch f/4 fast Newtonian's collimation from the other night. Unfortunately I only managed to pull off only three strings of galactic images. The sky was a Pickering 5 though transparency was pretty shot because of the quarter moon illuminating the high-altitude ice crystals. However, ground level humidity wasn't that bad, somewhere around 65%. A Bortle 3 to 4 skies depending on the hour.

The image of M-51 is the product of a Stakker-Lite experiment using 4 frames/lights totaling 316 seconds. 2X crop. Calmer air and less upper level turbulence would have resulted in a sharper image and the lack of color in M-51 is the direct result of using an unmodified Canon EOS 77D DSLR. I'm definitely going to get this camera modified this Spring.

The second image is another 4 frame/light stack of M-106, my first time imaging this Seyfert II galaxy. You can also see NGC4217, 4226, 4232, 4231 and 4248. Total data time is 358 seconds, full-frame.

The third image is a 6 stack of M42. I'm trying to get a good exposure spread in hopes of revealing the Trapezium in M42's inner core. It didn't quite work. Total data time is 200 seconds.

The fourth image is a single-frame of the same. With single-frame you just have to live with hotspots despite ones best effort in taming the over-exposure beast. 70 second exposure at ISO 1600.

All images were captured by an unmodified Canon 77D DSLR at ISO 1600. Also, in a change from previous "Stakker-Lite" images, all in-camera noise reduction circuitry were employed. As a result I believe the stacked images are far more pleasing. In fact, when using such small numbers of frames to yield a stacked-image, without flats, bias or dark frames, if your camera has such in-camera image processing you would be wise to employ them. In the Canon 77D and 80D series, each has both high ISO noise reduction and long-exposure noise reduction capabilities.

[TheButcher]

Very nicely done Henry!

[Mac]

Great captures Henry... I recently imaged M106 and yours is much clearer than mine at 3x the imaging time.

Good job.

[Hankmeister3]

Very nicely done Henry!

Thank you, TheButcher, I try hard … really, really hard. I can't wait for my first full night (okay, maybe a five hour session) of DSO imaging for 2020. I currently have a laundry list of DSOs I want to image given my new post-production techniques. If the weather forecast holds for Wednesday, I'm going to do some lunar photography with my Meade 10-inch f/10 SCT. I'm hoping for some tranquil air …. wahahaha!

[Hankmeister3]

Thanks, Mac. How's your new observatory construction coming along? Post a photo here on my thread if you have one of your work-to-date.

[Juno16]

Henry, you never cease to amaze!

Another set of wonderful images!

High ISO noise reduction. Very interesting. I guess using that feature helps with dark frame subtraction in leu of shooting darks.
Cool move!

Very nice work!

One night you will get that “5” hours!

[Mac]

Thanks, Mac. How's your new observatory construction coming along? Post a photo here on my thread if you have one of your work-to-date.

The Knollwood Observatory became Lake Knollwood after a 2" deluge a few days ago. I had not put in the drainage for the area that will contain the building. I had to remove the grass and a few inches of soil and uncertainty in my finances I held off ordering the materials. My largest customer paid me the many thousands I was owed and I feel secure with the bank balance once again.

However, as I type this they are on their way with delivering the concrete and 90% of the materials.

My 5' pier with 8" pipe is in the process of construction and should be done next week. The pier hole is 48" deep and I hope to start putting the concrete in today. Skies are clearing and we are on our way to 3 nights of mostly clear skies.

[Hankmeister3]

Thanks, Jim, for your observations. That's my thought exactly, the in-camera high ISO noise reduction works very much like "dark frame subtraction." I was thinking the same thing when I chose the highest level of ISO NR that night. The in-camera NR software appears to also help with the ultimate need for "flats", too, and maybe that's actually the function of the long exposure NR software and not the high ISO NR. I just don't know at this point. Maybe you or someone else has some thoughts about the rough equivalence between ISO NR and Long Exposure NR in Canon EOS cameras and how that may relate to "darks" and "flats." I suppose I could switch them off and on during several different strings to see what one NR feature is doing as compared to the other NR feature. But with the weather the way it is, and sky time very limited on a day-to-day basis, I don't want to waste time trying to reverse engineer my understanding of what Canon's NR software is actually is doing. So for the time being I'm turning the two NR features back on to their highest processing levels and charging full speed ahead. I can figure it all out later, if there's any real figurin' to do.

Maybe this is why my earlier single-frame captures were yielding some nice results because I had both NR features turned on when I was imaging. However, the camera is tied-up for about as long as the original exposure time itself when it's going through it's NR processing regimen. That is, a two minute exposure will generate a "Busy" alert in the LCD window for about 2 minutes as the camera is internally "processing" the image. Hmmmm. But using both NR circuits appear to have also improved my 3 to 6 frame stacks by overcoming the background "clumpiness" that a short stack will generate without darks and flats. Any more frames than that seem to overcome the Canon's NR software's ability to simulate "darks" and "flats".

[Juno16]

Really interesting information Henry.

I never use those functions with my Nikon’s. The main reason is that I shoot darks (which I really don’t enjoy). Also when shooting many subs, doubling the exposure time would consume huge amounts of time. In your use, I can surely see the big benefits.

Great job with these targets!

[Hankmeister3]

Thanks, Mac. How's your new observatory construction coming along? Post a photo here on my thread if you have one of your work-to-date.

The Knollwood Observatory became Lake Knollwood after a 2" deluge a few days ago. I had not put in the drainage for the area that will contain the building. I had to remove the grass and a few inches of soil and uncertainty in my finances I held off ordering the materials. My largest customer paid me the many thousands I was owed and I feel secure with the bank balance once again.

However, as I type this they are on their way with delivering the concrete and 90% of the materials.

My 5' pier with 8" pipe is in the process of construction and should be done next week. The pier hole is 48" deep and I hope to start putting the concrete in today. Skies are clearing and we are on our way to 3 nights of mostly clear skies.

"Lake Knollwood", Mac? It does have a nice ring to it … heh! Wow, if the weather holds it sounds like you'll be well on your way to having a functioning observatory in a month or two. Feel free to post and update photos on any one of my current forum pages. Or you can email them to me. I'm interested in seeing how you're putting it together.

[Mac]

I got the concrete pier in yesterday with ~1/2 ton of concrete. Seems like a major overkill yet I see some with 1.5 tons.