M101 with Epsilon 130D

[GalaxyGael]

First galaxy test on the new epsilon 130D, which at 430mm is a bit wide. Testing also Gain 0 which gives a ~900 ADU background and quite a bit more noise compared to gain 100 in my skies. Best FWHM star size was 2.4". 

Tak Epsilon 130D @ 430 mm

ASI2600MC Pro, Gain 0, -10C

iOptron GEM45, ASI290MM mini on OAG

307 x 180s (~15.2 hrs). Processed entirely in APP.

Show here in full view (reduced resolution) and also a crop.

 

 

Edited March 13, 2022 by GalaxyGael

[tomato]

Great M101, nicely processed in APP.👍

[Allinthehead]

Lovely wide field image, you have that Epsilon singing.

Funny you should mention gain 0 vs 100 as I'm currently imaging at gain 0 and for now I'll continue to do so. Lower fwhm, longer subs and better star colour. As you already pointed out sky conditions may well dictate what is optimal. 

[juno16]

M101 is a challenging target to capture and process. You have produced a wonderful image Colm. Nice details and colors. Ha areas stand out very well. Nice gray background and very pretty stars. Excellent work!

[Xiga]

Lovely M101. Nice subtle processing and not overdone on the colours.

I've been sitting on some data of this myself. Struggling to find the time to process it though. Hopefully soon! 

[GalaxyGael]

3 hours ago, tomato said:

Great M101, nicely processed in APP.👍

Cheers. While I used to pre-process in APP and then a little in PS, I do 100% in APP now and try to add more subs/time to deal with the stack quality. Its a simpler affair but there are a lot of tricks in APP for post processing that I knew since version 1.05x a few years back that I use now instead and it keeps it from any over processing, to me anyway.

[GalaxyGael]

20 minutes ago, Xiga said:

Lovely M101. Nice subtle processing and not overdone on the colours.

I've been sitting on some data of this myself. Struggling to find the time to process it though. Hopefully soon! 

I seem to be going back to yesteryear when I used minimal processing since the asteroids were the target not the image! And I like what APP can do when it is given enough half-decent data for post-processing. there are lots of ways to control color and background that are not obvious and are logged way back in discussions since version 1.05x, and by design it prevents me from poorly overprocessing  (in my opinion anyway).

[GalaxyGael]

1 hour ago, Allinthehead said:

Lovely wide field image, you have that Epsilon singing.

Funny you should mention gain 0 vs 100 as I'm currently imaging at gain 0 and for now I'll continue to do so. Lower fwhm, longer subs and better star colour. As you already pointed out sky conditions may well dictate what is optimal. 

Thanks Richard. It is a nice scope to use. I'm still on the fence with diffraction spikes to be honest having used Mak-Newts for years, and the odd refractor.

And it was your comment somewhere that made me try to gain 0 option. I dont have a decent data set to compare, but I think it is a bit noisier even with 307 subs (background ADU ranged from 850 to 2100 with some moon, so the low ones probably had an influence there) but the FWHM was lower, between 2.1 for small stars and 2.7 for big ones, averaging about 2.4. the 4.5" refractor was between 2.8-3.1". I'm guessing DN is a tad better but I have not tried gain 100 on the epsilon, but the yellow stars are certainly yellow to their core at gain 0 even though some come through at the 65563 counts in 180s. I might stick with it as there seem to be a few clear night this week with full moon.

Edited March 13, 2022 by GalaxyGael