Processing Dark Nebula and dust

Eric,

Have you ever processed lights with different exposure times with darks with a single exposure time before? ASI cameras suffer quite a bit from amp glow and I have noticed that my ASI1600MM *needs* darks with exactly the same exposure time as the lights. That’s why I created a dark library with varying exposure times so I am prepared for an imaging session exactly the same as yours.

Wouter

Dark nebulae are difficult, it's something that APP might have a better tool for in the future. I notice some have more success really getting the dark stuff out using Photoshop. I unfortunately don't have much experience with that though.

Hi Wouter, 

I have never tried using a single dark exposure time with lights at different times. I when working on this photo I did a multi session with dark frames that matched the times of each of my light image sessions. I have quite a good sized dark library 😊  

What was also odd for me was that when I saved my preview after getting the image the way I wanted, the tiff and jpg files didn't look exactly like the preview. I had to adjust the image in Adobe Lightroom. 

Hi Eric,

I too have Bortle 5 skies. I love APOD images showing smokey gray nebulae against dark deep space. I just don't think that Bortle 5 skies are dark enough. For me it shows itself as a region relatively devoid of stars but that's about it. One time I did have moderate success showing the nebula as a shade lighter than space but the required exposure was pretty extreme: 30 minutes luminance filter. In a single sub-frame I could see it but the downside was that deep space was 20,000 ADU. So what I figure is that the nebula is right at the level of sky brightness for Bortle 5 skies. You can increase your chances by imaging close to the zenith, an angle where the atmosphere is thinnest.

Oh yes, agreed, darker skies ofcourse. 🙂