Saving of live stacked images

[SteveJP]

Hi,
Given my ASI2600 has very low read noise and ignorable dark noise, and that I image in a Bortle 2 site, my optimal sub-frame length is only 4 seconds. The main problem with this is of course if I were to image for an hour or so, I get an impractical number of frames occupying a humungous amount of disk space, not to mention the time it would take to stack etc.
So - I was inspired to use SharpCap's live stacking feature in conjunction with the option to reset the stack periodically. For example, I used 5 sec exposure and reset the stack once minute, resulting in stacked images with 12 frames each. The plan would be to put this through the normal processing process, in my case, using Pixinsight. Thus works fine, except each stack is written to the disk in a different folder, complete with meta data, processed images in both 16 and 32 bit forms. This means I have to extract a the 16 bit raw image from many folders, and consolidate into another folder for processing.
I tried experimenting with the various options without success. What I really want the 16 bit stacks alone written to a single folder, just as if I'd used the standard capture method. If there is a way to accomplish this, I'd love to know. If not, then perhaps it's an idea for a future enhancement.
Cheers
Steve

[jolo]

Hi Steve,

Have you tried some advanced copy tools, where you can filter what files to copy and put them into a single folder? I think copywhiz may do the trick https://www.conceptworld.com/blog/index ... -copywhiz/

Also, you are not limited to 4s subframes, as this is only the low noise-limited exposure time. You may do longer subframes, if tracking is good, like 30 or 60s, and set the gain to a lower value to not oversaturate stars.

Lucas

[SteveJP]

Hi Jolo,
I could try some third party tool like that, but it's really an inconvenient cludge. Much better if SharpCap could simply put the files in one directory.
Of course I could do longer subframes, but what I'm trying to do is potentially stack a thousand or more frames to drive down the noise. A combination of live stacking and subsequent stacking of the stacks with PI or similar might make that practical.
Rgds
Steve

[admin]

Hi Steve,

I think that you should be able to set this up using the custom filename template options in the SharpCap settings - there are templates for live stack saves, live stack raw frames and live stack processed saves, all of which can be customized so that you decide which bits go in the filename and which go into the directory name. See https://docs.sharpcap.co.uk/4.0/#Filename%20Templates

Also, it's worth noting that the recommendation for exposure is a *minimum* value - you can happily exceed that value with no ill effects on the final image until one of the following happens

1) You encounter issues with trailing visible in the images due to tracking issues
or
2) The light pollution background in every image becomes big enough to cause problems (histogram peak gets to the 20 or 30% point)

By considering this, you may find a somewhat longer exposure that gives you fewer files while still not encountering either of the above two issues.

cheers,

Robin

[SteveJP]

Hi Robin,
I usually do use much longer exposures, if for no other reason than the min exposure results in too many files and a ridiculously long post processing time. I wanted to try a much larger number of short exposures for the same overall exposure time to see if the noise was reduced.
I'll have a look at your suggestion.
Thanks
Steve.