NGC3718, Luminance from light polluted back garden

[emyliano2000]

Hi guys. I recently had a go at NGC3718 in the hope that I could get something nice out of it.

The first night I shot 60x240sec with my qhy183m and baader L filter at unity gain (11).

I stacked them and got some horible gradients.

I decided to have another go at it using gain 0 and increasing the exposure to 300sec. I shot 70x300sec but the stack, the same as my first try, had really heavy gradients.

Listening to Olly's sugestion to look on the internet for how to properly use the GradX plugin in photoshop, I decided to stack all of them and have another go at it.

This is my result. 59x240sec gain 11 and 66x300sec gain 0, stacked in pixinsight with 200 bias, 30 flats and 50 darks for each session, using the long LightVortex tutorial.

It can probably be better but I don't know how to do it. 

If anybody wants to have a go at it, I will post the stacked file here.

I have some RGB data too but I've been concentrating on getting something out of the luminance.

Emil

[geordie85]

A very nice image. I see you've got the 183m working very well for you. I've always used unity gain with the 183c, how big a difference did you see using 0 gain? 

I'd like to have a go at the stacked file if you're happy with that. 

[emyliano2000]

Thanks.

To be honest not a big difference in detail but the stack came out much cleaner. Plus I'm not an expert to say how things should really be ?

Maybe it was because I increased the exposure and got a few more subs. I will still have to test it but I was thinking of using gain 0 when shooting luminance, gain 5 when shooting  and 11 when shooting narrowband. 

[emyliano2000]

Here are the tif and fit files for anybody wanting to have a go. It's the same image but one is saved as tif and one as fit.

NGC3718 Pix Lum (28,29,31.03).tif

NGC3718 Pix Lum (28,29,31.03).fit

 

 

[Demonperformer]

Not bad at all. A couple of nice galaxies with several "tiddlers" as well.