Sharpcap images with ASi1600

[John.Sankus]

I can take sequences and feed them into astrotoaster which then pulls more detail out of my images with auto expand and other tweaks.

With sharpcap (I have stable 2.9x and beta 2.10 as well), I can let it stack for quite some time, taking exposures ranging from 60 seconds to 300 without any major issues in guiding, etc - but the image displayed never seems to pop or show any really good detail when I play with the histo. Is there something I am missing or doing wrong?

The images I take seem washed out, light blue overcast to the entire field of view, playing with the black and white points brings out a little detail, but nothing that really makes it show good detail of the image (for instance M51). If you need an example of what I am seeing, I can provide that later when I get home from work.

[admin]

Normally the best way to pull out more detail in the live stacking is to slide the gamma slider on the left hand side down - this boosts the low intensity areas and pulls out the nebulosity. With a small number of frame this will show a lot of noise, but as the stack grows the noise will reduce leaving you (hopefully) with an excellent picture.

What you can also do is check the box that saves the individual frames, then re-stack afterwards in your favourite stacking software. LiveStack in SharpCap isn't always going to do as good a job as dedicated stacking software, but is much more immediate...

cheers,

Robin

[John.Sankus]

Thanks Robin, I will try that my next time out and let you know how it goes.

[John.Sankus]

Robin, i want you to check out my recorded session I did last night with the ASI1600 and Sharpcap.

https://www.youtube.com/watch?v=oXogb43tzRI

I ran into an issue using a new focal reducer and too much spacing at first, so forgive the jumbling around until i get it sorted, but can you critique my use of Sharpcap and give me any advice to improve?

Thank you!

[admin]

Things that jump out after a quick skim through

* Using RGB24 mode - consider using RAW16 for this sort of target (but this uses more memory - test with a short stack and then save to check you don't run out of memory). The dynamic range of M42 is enormous and using the higher bit depth mode will help capture it

* Overexposing the core of M42 - an overexposed region is going to be white whatever processing you apply. Better to wind down the exposure/gain to at least reduce the over-exposure here. The nebulosity will still show up once you have stacked enough frames

* You aren't using the gamma control (to the left of the live stack histogram) to stretch the shadows, which will pull out the faint nebulosity. Slide this downwards and watch how it affects the red adjustment curve on the histogram.

cheers,

Robin