How do I set the capture failure timeout period to be longer?

[Borodog]

I take LENR images sometimes and SharpCap seems to sometimes timeout during the dark capture portion. Is there a setting somewhere to change that timeout period? If not, can there be one?

[admin]

Hi,

LENR? A quick web search indicates that might be an acronym for Low Energy Nuclear Reactions !!?

Anyway, the timeout when capturing a frame rather depends on the type of camera - some brands have support for varying the timeout and others don't. However, the typical situation is that if the frame hasn't arrived after the default timeout, it usually isn't going to arrive at all, and the best thing to do is to try capturing another frame and hope that one works. In most cases, SharpCap does that and reports a dropped frame.

What model of camera are you using and do you have a log that shows the timeouts? I can dig a bit further with the contents of the log to show me what might be going on.

cheers,

Robin

[oopfan]

Robin,

LOL, yes it took me a lot of searching to discover that it means Long Exposure Noise Reduction (LENR). Just think of all the time we could have saved if he had told us what it stood for in the first place. Not the friendliest approach to human communication! People come to the SharpCap forum to learn from others. Using acronyms is one way to turn people off.

The best I can figure out is that he is alternating between taking a Light frame and then a Dark. I'm not sure why he would receive a timeout.

Brian

[iamhondo]

LENR is a feature of Canon cameras (and maybe others). After the camera takes a specific length exposure, the shutter closes and another image is taken. The second image is a single-use dark image to correct hot pixels, etc in the light frame. The camera isn't "done" with the image until it has collected both images and performed the adjustment. So from the start of the image to the completion point the time period will be 2x the specified exposure length plus a bit for data motion, calibration and other housekeeping.

If the image capture software expects a 30-second exposure to be done in 30-ish seconds, it might get antsy about the long delay. From the camera's perspective, there's no timeout because it's still working on the image. Of course if LENR is disabled, then the net time of the exposure will be shorter.

LENR isn't just on or off. There can be conditional circumstances that allow or suppress LENR. It looks like the details might vary with different models. The on-line manuals probably give more details.

Of course if the OP isn't using a Canon camera, this whole post is a "never mind".
Joe

[admin]

Ah,

that starts to make a bit of sense - I have encountered that 'take a dark straight away' behaviour in DSLR cameras myself, but never when trying to run them via the ASCOM driver.

@borodog - can you confirm that we are on the right track here? Doubling the time taken for the exposure would very likely lead to a timeout, and it will definitely need to be user adjustable as users of non LENR cameras don't want to be left waiting a whole extra exposure length before finding out an exposure failed.

cheers,

Robin

[Borodog]

My apologies; I thought "LENR" (Long Exposure Noise Reduction) was a familiar concept among astrophotographers.

But yes, that is the issue. If I turn on LENR in the camera, and SharpCap requests a 30s exposure, the actual time of arrival will be > 60s later. A user adjustable timeout would fix it right up.

[admin]

Ok, thanks for the confirmation - it's on the todo list now.

cheers,

Robin