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Is anyone using the Logitech C920 cam, at least 6 cam setup?

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I am guessing no users are.

Has iPi even tested 6 x C920's?

I found a local deal on 6 of these, but before I invest, I was wondering if the tracking is actually any better than with PS3 cams videos at lower resolution.

How much bigger will it make the video file at 1080p? I would expect it to be a bit larger even using JPG compression recording.

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We have tested recording with 6x Logitech C922. Compared to C920, it is capable of 60 fps (at 1280x720 resolution). That's why we consider it as an alternative to PS Eye. AFAIK C920 has maximum of 30 fps.

Compared to PS Eye, it has slightly less vertical FOV but greater horizontal FOV. It produces better picture in low lighting conditions. However, tracking quality does not differ substantially as our full-body algorithms do not actually use that high resolution.
Space usage for 6 C922 in 1280x720@60 is about 35 MB/s (raw JPEG frames obtained from cameras) while for 6 PS Eyes in 640x480@60 (background subtraction) it's about 25 MB/s. Tracking speed for Logitechs is somewhat lower as expected, but I cannot provide specific numbers.
Moreover, Logitechs are more demanding of a host PC's performance. We only tested distributed configuration so far with 3 cameras per a laptop, and there were some performance issues we've already fixed. And still, it's doubtful whether recording with 6 cameras connected to a single desktop is possible.

All in all, I'd recommend you to stick to PS Eyes for the time being as no considerable improvements are expected from Logitech cameras when using with our software.

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Thanks for the reply, that is what I was thinking also, but without testing myself it is impossible to know, but if 6 wouldn't run on a single PC, that's a stopper for me right there.

I expected file size to be a bit larger, but I didn't realize until I checked that the C920 only records at 30 fps, which all are, sooo, another stopper.

It was just a good deal from vocational lab near me that used them and bought too many, so for $20 each I was gonna ask here first.

Thanks again, you have confirmed my doubts to being viable over the PS3 cams.

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