SharpCap Forums

I found Custom Capture Area very useful for the ASI174MM but was disappointed that it is missing for the ASI294MM, even though it is present in ZWO's ASIstudio. Custom Capture Area skips uninteresting areas of the image, increases frame rates, and allows more flexibility than the predetermined selected areas.

BTW searching the forum I found interesting comparisons of CMOS chips. Robin prefers the latest IMX533 and IMX571 because they have low afterglow as well as 14- or 16-bit output. I chose the IMX294 because it has bigger pixels and 14-bit output (in mode 2), is cheaper, and bigger than the square IMX533. I may yet change my mind, since the larger chip shows vignetting with a 1" C-mount lens, and most MFT lenses don't have focus lock screws. Custom Capture Area would help with the vignetting.

Hi,

Right now custom resolutions are not available for the 294MM because of the extra complexity introduced by the two read modes of 11 and 47 megapixels.

I will note down this request to fill this functionality gap - I just had a quick look and unfortunately it's not as easy to do as I hoped, but definitely should be possible.

cheers,

Robin

Thanks Robin, I understand that. The 11M mode with 14-bits is the most interesting, and what was originally intended by Sony. The 47M mode was apparently unlocked "because it was there", but with tiny pixels at 12-bits it is not interesting for low-light imaging IMHO. Cheers, Alan.

Hi Alan,

interesting... If you are not interested in the 47 megapixel mode then maybe the easiest fix is to have an option to turn that off in SharpCap. That would make it really easy to go back to 11 megapixel and custom ROI with the 47 megapixel turned off.

thoughts?

cheers,

Robin

Robin, an option to turn off 47M pixel mode would be great. BTW, I was perhaps a little too dismissive of small pixels - I understand they are useful for planetary imaging, and Ch. Buil in his review of the ASI294MM likes them because he can then do median filtering to reduce isolated noisy pixels before binning. But since SC doesn't do median filtering, that's not relevant to me. http://www.astrosurf.com/buil/asi294mm/
Thanks for a great (simple) solution, Alan.

So how do I delete Custom Capture Areas when they can be set - eg for the ASI174MM ? With ASICap the equivalent Custom "Resolution" (badly named) dialogue allows me to delete Areas as well as add them. Even resetting SharpCap parameters didn't remove my Custom Capture Areas. I suppose they are in a file somewhere? It's great that I can set Custom Capture Areas with Sequencer, but I can't set the offsets "Pan" and "Tilt" so far as I can see.

Experimenting with Custom Capture Area showed me how useful it is, especially since it is preserved (including offsets) when SharpCap restarts.

Hi,

the custom area is remembered, but offsets are not (by default) - although offsets are set automatically to center the custom area on the full sensor.

If you want to save the offsets when they are not centered, use a capture profile.

Unfortunately there is no easy way to delete a custom area - they are buried in the registry rather than in a file.


cheers,

Robin

Thanks Robin. I will look into using a capture profile. In my application, the ROI is constant, and it would be good to be able to define that within the complete FOV, with size and offsets, once and for all.
Cheers, Alan

Hi Robin. Thanks for today's SharpCap update. I installed V.4.0.9381 and found the option to "Ignore small pixel mode on the ASI294MM" under File/Settings/Hardware. Unfortunately, when I check it or indeed any of the camera settings, then click "Apply" and "OK" these settings are not remembered, since they are unchecked if I open Settings/Hardware again. I tried "Reset Settings" for all settings, re-started SharpCap, and indeed all settings were reset. But that didn't help with setting the camera hardware. There was no way that I could effectively change those settings, and of course the small pixel 46Mpixel mode was not disabled, and there was no custom "Resolution" in the 11Mpixel mode
Kind regards, Alan

Hi Alan,

rats... I missed one line of code and that was the one that would save the settings back to the registry.

I will do another update, as that is a simple fix.

cheers,

Robin