Soul Nebula

[paulgrover68]

I took a window between sunset and the moon becoming bothersome to have sneaky shoot of the soul nebula. It was fireworks hell for the full three hours, but fortunately they all stayed out of my part of the sky.  I use nights like this for experimenting and tonight I expanded shot at 240 seconds rather than my usual 180.  I'm gradually pushing up to explore the limits of my filters and my sky.  I used the Optolong L-eNhance - which is a filter I'm growing to love.  My stars are streaking a bit more at the edges as my filter drawer lost me some of the extra spacing I introduced.  So planning on picking up a couple of spacers to fix.

 

[MarkAR]

Looks really good, longer subs work well.

[Dmack1]

That's really good. Nice contrast and definition on some of the outer clouds.

[AstronomyUkraine]

Posted by: @paulgrover68

I use nights like this for experimenting and tonight I expanded shot at 240 seconds rather than my usual 180. 

Nice image, and very good detail. What gain are you using with the ASI294?

[GazAstro]

Very nice 

[paulgrover68]

@AstronomyUkraine I'm at unity gain and shoot at -10.  I'm still getting to know the camera, so I tend to play it safe.

[AstronomyUkraine]

Posted by: @paulgrover68

I'm at unity gain and shoot at -10.  I'm still getting to know the camera, so I tend to play it safe.

I shoot at unity gain for NB filters which is 139 gain on my 1600, for BB I usually drop it to 76 gain. I shoot at -20 all year, it helps with the noise.

[paulgrover68]

@AstronomyUkraine That's an interesting combination.  I started guiding in July, so have been moving from quite short exposures to longer ones.  When I introduced my L-eNhance found adding a minute to my then 2 minute subs offset the need to increase the gain. 

I think there's a lot more exposure time to be had from my sky, but aircraft can be problem in my location. So I may consider increasing the gain to reduce the overall image time on the tri-band.  I think this might be my next area of experimentation. 

[AstronomyUkraine]

Posted by: @paulgrover68

That's an interesting combination. 

It was after a lot of experimentation. I have tried 200 gain for narrowband, without any noticeable increase in noise, but my histogram starts creeping to the right too much. With gain at 139, my histogram is about a third away from the left. With broadband. I leave the gain as is, at 76, and adjust my times, ranging from 30s to 2 minutes.