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Actual Full Frame Speed

ZWO ASI676MC
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BillyBoyBoy avatar
BillyBoyBoy avatar
Unlike some ZWO cameras, the specifications on the ASI 676MC seem a little lean when it comes to what exactly the frames per second specification actually means.

I see a published "Max FPS" of 31.2.  Is that full frame at its full 12 bit depth, or some compromised setting combo like lower bit depth with a subframe?

Thanks for any use insight!

Bill
Well Written
Tony Gondola avatar
Tony Gondola avatar

In information I found (mostly AI so beware) is that it delivers 31.2 FPS at full resolution. But of course, most people will use a camera like this with an ROI smaller than the full frame for lunar and planetary. Doing that will of course, deliver a much higher frame rate.

BillyBoyBoy avatar
BillyBoyBoy avatar
Thanks. Wondering if there are any users of the camera that know.
Oskari Nikkinen avatar
Oskari Nikkinen avatar
Max frame rate is most likely at a lower bit depth but still full frame. Your capture framerate is entirely dictated by 3 things - exposure time, file size, and file transfer speed. The last one is determined by the USB ports on the camera, the USB port on the receiving PC and the cable in between. For longer videos your hard drive performance can also limit speed (when ram fills up with buffered frames).

Not sure why this matters to you so much. When you are doing planetary or lunar you are almost certainly going to be doing 8-bit raw recordings with a much smaller ROI than full frame, at which point exposure time limits the frame rate far more than anything else. With planetary this is certainly the case, with ROIs typically in the 480p width ballpark.
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