Can I save ignored frames in Live Stack

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chongo228
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Can I save ignored frames in Live Stack

#1

Post by chongo228 »

I've had Sharpcap ignoring frames that I suspect are usable. When it ignores them it doesn't save them. I tried to find a setting to allow it to save every frame but couldn't.

I'd like to decide later which frames are worth keeping.....is this an option. If not can you add it?
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admin
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Re: Can I save ignored frames in Live Stack

#2

Post by admin »

Hi,

currently SharpCap only saves the raw images for frames that are added to the stack – as you note it discards the frames that are ignored due to one of the filtering options. Right now there's no way to override this default behaviour, although I will consider this as a possible feature for a later version of SharpCap – thanks for the suggestion.

Cheers, Robin
chongo228
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Re: Can I save ignored frames in Live Stack

#3

Post by chongo228 »

Thanks, perhaps i'm not doing something correctly. I noticed it drops frames when I switch a setting. For example when I went from 10 second exposures to 30 seconds on M42 last night. I was shooting 10 seconds and it didn't drop any frames. Before I went to 30 I did the following.....

Pause live stack, cleared the stack, changed the file name in the box at the tool bar at the top, changed my exposure time to 30 seconds and hit resume.

When I hit resume it dropped the first frame or two. I noticed the histogram didn't change when I hit clear....it still showed the stretch of the 10 second subs. I exited live stack and restarted. The old histo was still there. It then dropped the first 2 frames but after that seemed to do fine and the histo finally changed to back to linear un-stretched. Later when I went to 180 seconds it dropped the first two also....I ended live stack and went to the "start capture" button.

Is there another step I need to do in live stack between filter/sub exposure length settings? I remember this happening last week when I was shooting Ha on the same target. I seemed to happen when I would change exposure length.
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Re: Can I save ignored frames in Live Stack

#4

Post by admin »

Hi,

if you look in the log tab of the live stacking UI then you will hopefully find information that will say why the frames are being dropped when you start changing the settings. As far as I'm aware what you are doing should be correct I'm a little bit surprised by the problem that you are seeing. If you can collect that information from the log tab if there is anything useful and share it then maybe I can work out what's going wrong and then fix it.

Cheers, Robin
BlackWikkett
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Re: Can I save ignored frames in Live Stack

#5

Post by BlackWikkett »

chongo228 wrote: Tue Jan 08, 2019 12:58 am Pause live stack, cleared the stack, changed the file name in the box at the tool bar at the top, changed my exposure time to 30 seconds and hit resume.

When I hit resume it dropped the first frame or two. I noticed the histogram didn't change when I hit clear....it still showed the stretch of the 10 second subs. I exited live stack and restarted. The old histo was still there. It then dropped the first 2 frames but after that seemed to do fine and the histo finally changed to back to linear un-stretched. Later when I went to 180 seconds it dropped the first two also....I ended live stack and went to the "start capture" button.
Hi chongo228,

When you pause in Live Stack it pauses but as soon as you click clear the Live Stack starts attempting to stack frames again. You may have dropped the frames as you were changing exposure settings. i found that doing this while Live Stack is active can cause frames to drop until you have at least two new frames of the same exposure. Your second point about the old histogram is normal in Live Stack. This is due to the new Live Stack, in your case 30 seconds from the previous 10 second, needs two frames to actually stack and update the Live Stack histogram. In effect you're not really missing anything since you don't want the old 10 second frames rather you want the new 30 second frames.

If you don't want to see drop frames after changing settings follow this:
1. Pause
2. make your exposure or settings changes
3. clear Live Stack which will resume the stacking

Hope this helps
-Wikkett
BlackWikkett
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Re: Can I save ignored frames in Live Stack

#6

Post by BlackWikkett »

Sorry for the Double post the forum coughed up a weird error that I didn't catch and now there's this double post. If an admin can please remove one.

-Wikkett
chongo228
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Re: Can I save ignored frames in Live Stack

#7

Post by chongo228 »

Wikkett.....I think you are correct. I did notice it seemed to start stacking on the 3rd image and only after I adjust a setting. I never dropped a frame in the other 4 hours of shooting. I plan to shoot again tonight or tomorrow....I will test your method out and report back.
chongo228
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Re: Can I save ignored frames in Live Stack

#8

Post by chongo228 »

I think Wikkett's method worked. I had no dropped frames after a settings change.


After a while of shooting I did start dropping frames. I dropped 3 or 4 in a row. Not sure why.....the sky was clear and I didn't touch anything. It had been stacking perfectly for over an hour. I cleared the stack and after that it performed perfectly for the rest of the night. Attached is a screen shot I took after I cleared it and the first new frame rolled in. I should have copied and pasted the log but I wasn't thinking....hope you can get enough info from the log in the picture to give me some ideas

I'd really like to have a setting for keeping deleted frames....or at least a way to view it. If my guiding, focus, or dew heater failed the fastest way for me to tell would be to see the last frame or look at them the next day. Currently I have no way to tell if it's something i'm doing or an error in SC.

Thanks for all the help.
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BlackWikkett
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Re: Can I save ignored frames in Live Stack

#9

Post by BlackWikkett »

Hi Chongo228

Check your setting on the Alignment tab in live stacking. You only need about 15 stars to align the frames. Adjust settings in the Alignment tab until you have less stars detected. Your stacking may be failing because of too many stars detected or even detecting hot pixels as stars. The Live Stack documentation explains what these settings do. Your log is showing 1000 +/- stars detect which is way to high and not necessary to get good stacking results.

Dropping a frame or two while live stacking shouldn't be a worry it happens to me all the time. In my case i'm usually only using 30 second or less for exposures and the few dropped frames aren't going to make or break the image. Have a look in the gallery I have a few post there with some that are exclusively live stacked images without any outside of SharpCap processing.

-Wikkett
chongo228
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Re: Can I save ignored frames in Live Stack

#10

Post by chongo228 »

I realized last night that it was dropping frames on my longer exposures. It never dropped a frame on my 10sec or 30 sec. Maybe my stars are blown out or too many stars like you said. I'll try to lower some settings and see what happens.

My original problem of dropping frames after adjusting settings is resolved btw. I now hit clear stack last as you suggested in a earlier post.


Thanks
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