NGC 3718 & 3729 with 5,5 hour on DSLR

[Jannis]

So, finally had a go at processing this target.

NGC 3718 and NGC 3729 with a magnitude of 11.4 and 12.4 i think are roughly 52 million light-years away, and the Hickson Group 56 wich i also captured is about 400 million light-years away with a magnitude from 14.8 to 17.

I'm very pleased to have been able to capture anything that faint and far away at all, as i didn't expect me to be able to.

I just simply had to ignore the fact that i was having tracking/guiding problems on my HEQ5, used an unmodded DSLR with no coma correctors, no filters, used incorrect flats (camera taken off between), bias and darks (completly wrong ISO and exposures, as well as temp), and give it a go as good as i could in photoshop anyway.

Exposures for light frames are following:

109x 2 min ISO 1600

6x 13 min 20 sec ISO 400

3x 6 min 40 sec ISO 800

1x 10 min ISO 400

1x 1 min 40 sec ISO 3200 (how i managed to even get this frame, i don't know, but i accidently stacked that one too, lol)

No calibration frames taken, all frames i used was from a previous session. Thay was not ideal, but it seems like they still did better then none.

Stacked in DSS with kappa-sigma clipping, and processed in photoshop.

It's a bit noisy still, and color balance is off i guess, but i guess i shuold be happy as it is for now with the current data and photoshop skills i have.

High res is available here: https://www.dropbox.... 3718-5h30m.png

[Gina]

Nice

[nightvision]

Wow that is deep, such unusual shapes those two foreground galaxies. It's just incredible that a 200mm scope given enough time can see that deep!

Well done, I must have a go when my obsy is built.

[Jannis]

Yeah, i was very surpriced by how deep i could go. Though, it was a real pain to get out any details at all out from the faint arms of NGC3718. I was barly able to get them showing up a tiny bit.

I guess 5.5 hours isn't really nearly enough data to get them to look good.

I don't think i can push my setup to much more then 13 min though, maybe 15 min. But if i can just get more frames, i Could be able to get some more details maybe. Time will tell, but for now i'm very happy with my result!

[JamesF]

Those are two very strange-looking objects

James

[Jannis]

Does anyone know if it's even remotely possible with my current setup to get the more faint details showing up with more subs? Like, if i take up to 20-30 hours exposure total instead, and maybe stay to 10-15 min exposures?

Or will the sky-glow in my low to medium light-polluted location be too bright so it's simply not going to be possible to process the difference between the sky-glow and the faint stuff no matter what exposures and how much total total exposure i gather?

I don't use any filters at all for now, but concidering the CLS-CCD filter and at least a coma-corrector for next season.

Current sky-glow limits me to about 12-15 min exposure at ISO400 stright up in the sky.