M42 in the City

M42 (the great Orion nebula) with the Running man nebula above.
Taken in front of my house in Portland Oregon on 3-30-2021 with Tracker and Bird lens…

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Technical Details

Is this a composite: Yes
D500 w/ 300 f2.8 lens with 1.4 tc)

32 -60 to 90 sec. light frames
4 dark, 8 bias and 8 flat frames stacked in
PP in Affinity Photo and Capture one 21.

So interesting and looks difficult to photograph. Do the colors come up naturally? Do you have to do anything special to manage the movement of the earth and/or the celestial objects? I think I see some here which is inevitable since we’re moving so fast. I see you’re using some specialized software. This is a type of photography I know nothing about.

I have no idea how you pulled this off, but this looks cool.

Thanks Ed and Kristen…
It takes a bit of time to master a Star tracker but once you do, You focus on your subject (in this case a spot in the sky) like any other photo discipline and shoot.
Since you are tracking at earth speed, you shoot 1-3 minute images and if you get focus right (live view ) they are tack sharp.
You stack a lot of them (1-2 hours optimum) along with dark frames (you shoot same settings with cover on lens for 10 frames or so) flat frames (images shot in daytime with cloth cover on lens looking at the sky), bias frames (you shoot with lens covered in dark room at 1/8000 sec), and stack them with special software (I use Astropixel Process, where you stretch all the data and then finish in PS or in my case Capture one and Affinity photo.

I took this one last night in cloud cover with 300 f2.8 lens and 1.7 tc with D500,
This is almost full frame vertical cropped from horizontal.

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This does seem like a lot of work but the results are amazing. It looks like something from the Hubble telescope.

I thought I replied here – forgot to hit Send again? Apologies!

You captured very pleasing colors and have a good start on nice detail. It looks very promising for what the dark sky map shows of Portland. Shooting deep sky objects is a frustrating endeavor but the satisfaction is worth the trouble. Watching detail be pulled out by the software is similar to watching a B/W print develop.

If you can get more like 5-6 hours of integration you should be able to pull out more mid-tone detail. As you go for more detail, the best NR becomes critical. The number of Dark and Bias frames is generally recommended to be at least twice the number of Lights, for the cleanest NR. About 20 Flats is generally recommended. Shoot the Darks at the same ambient temperature as the Lights.

Your stars are slightly elongated, probably due to polar alignment of the tracker not being optimal. Proper alignment is another frustration unto itself. The Pole Master is more accurate than a polar scope. Shorter subs would minimize the error.

I look forward to seeing more!

Thanks Diane, these are not in the same ballpark as yours. I just began trying this stuff, It is a pretty decent learning curve…
These also were just trials to see how big a lens I can get on they $400 tracker and 300 F2.8 is a beast so some star trailing is probably just how it will be using this lens. I bought a 135mm Rokinon that is a fav of the Astro crowd which I will probably use more when I get out to dark sky,
Where I live in downtown Portland is Bortle 8 at best and I am not using filters.
I am modifying an old D610 which should make a fine lens to use…
Your images are terrific.

For Bortle 8 this is an astonishing start. I’ve heard quite a few people say the “LP” filters are not that great. Dark skies are getting scarce – even the Alvord is disappointing, I think with dust so often in the air. After good air, the secret is integration time, enough dark, flat and bias frames, and maybe to a lesser extent, software.