sequence frames with delay

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donboy
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sequence frames with delay

Post by donboy » Wed Dec 06, 2017 1:26 am

Robin,

I would like to run a set number of frames and have a fixed delay in between downloaded captures. I tried using the settings provided and I couldn't get it to work.

Example:

Exposure - 60sec
Total frames to capture - 25
Delay between captured frames - 15sec

So how would I go about doing this?

Don

P.S. is it possible in the future that the Output Format could be saved in the camera profile?

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admin
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Re: sequence frames with delay

Post by admin » Wed Dec 06, 2017 8:30 pm

Hi Don,

set the exposure you want and then setup the capture start dialog like this
Capture.PNG
Capture.PNG (47.08 KiB) Viewed 27 times
That should do the trick.

I think the output format should be saved, but you need to uncheck 'Start Cameras with Auto output format' in the settings.

cheers,

Robin

donboy
Posts: 53
Joined: Sat Mar 25, 2017 1:57 am

Re: sequence frames with delay

Post by donboy » Wed Dec 06, 2017 9:00 pm

Robin,

I've tried what you suggested for sequencing with following:
60sec exposure
Sequence length 20
delay 10sec.
Output format .fits

What happens is the following:

Start the capture and immediately a frame is saved. Then the next exposure happens 60sec after the 1st and then the 3rd comes 60sec after the 2nd, etc. There really is no true delay in between exposures. Then sometimes after the delay count down another frame is saved. I can't get it to operate the same way twice. I really don't think this is working properly.

Don

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Re: sequence frames with delay

Post by admin » Wed Dec 06, 2017 9:12 pm

Ah, ok, I see. There is an interaction between this sequence functionality and the fact that frames are being captured all the time.

One feature introduced in 3.0 (I think) was that if you are using long exposures and capture a single frame (snapshot button or via the sequence), SharpCap will actually save the frame that has just finished if the camera settings are unchanged. This is good because it means you don't have to always wait to capture something and you can also save the frame that you can see on the screen (this applies for exposures of a few seconds or more).

This has an interesting interaction with the delay setup. Basically if it gets to the end of the delay and the frame that has finished most recently has not already been saved then that finished frame will be saved and the sequence will move onto the next step. It all depends on the relative lengths of the delay and the frame.

A better way to do this is to use the 'Frame Rate Limit' control to set a limit of (say) 1 frame per 2 minutes. Then just start capturing for 25 frames (no sequence, just set a limit of 25). Obviously this doesn't quite get your delay of exactly 15s, but it should be reliable.

A robust way to do what you are describing with a 15s delay will come along in SharpCap 3.2 where I am planning a still camera mode and a full sequencing tool.

cheers,

Robin

donboy
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Re: sequence frames with delay

Post by donboy » Wed Dec 06, 2017 9:30 pm

Sorry didn't quite understand what to set.

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Re: sequence frames with delay

Post by admin » Wed Dec 06, 2017 9:33 pm

This control - basically it causes SharpCap to limit the rate at which it handles frames from the camera.
Capture.PNG
Capture.PNG (12.06 KiB) Viewed 20 times
Robin

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