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Chronos User Discussion / Re: Long-term sustained capture (1TB of data) to SB or and network?

« on: April 24, 2022, 06:58:08 PM »

@Nikon1.. thanks for the suggestion.  Ill check but worry that anything going out over HDMI will be compressed.  Even MJPEG would be unacceptable compression for what I need.   But the idea of a looping collection, in uncompressed mode, could be interesting we'll see if it can be combined.   I've asked my student to basically look at using the  API raw frames at full speed to memory, then save the capture to esata where I can have a massive drive, then repeat the capture.   then at night we copy it over the network and process it.     Not sure how fast we can go but uncompress is critical for our analysis, even if its has larger temporal gaps.    It will be quite some time before we can get it setup and tested, just getting quotes for installing the power we need.

Thanks for everyone feedback.  Saved me going down a rabbit hole that would not have been productive.

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Chronos User Discussion / Re: Long-term sustained capture (1TB of data) to SB or and network?

« on: April 24, 2022, 12:16:16 PM »

Thanks for all the replies.     To answer why/what I would do this for, it is for modeling atmospheric turbulence in parallel with long-range imaging experiments. 
I'd save a few frames for visualization but mostly I'd process through a GPU or 2  to get per-frame estimates.  There are specialized turbulence sensors (I have a quote for one at $35K and 5 months for delivery )  but they don't produce images which I thought would help with understanding and evaluating our biometric data.     We have an event camera for some of these measurements but that is on backorder into mid-2023.   I'll may look at the feefly,  but maybe first do some experiments with the Chronos.  With that speed writing to SSD it is impressive.    And since I have the Chrons available though it might be interesting to explore first.


If I can capture for a second or so, save to NFS, then restart capture  I would be able to get data for estimates. (A separate GPU computer would read/process the files).     Even only get once per min,  I would at least get temporal atmospherics regularly during the day.   That would still be way more data about the turbulence than any other dataset in my space provides.

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Chronos User Discussion / Long-term sustained capture (1TB of data) to SB or and network?

« on: April 20, 2022, 06:21:38 AM »

We have a pair of 2.1 camera and have used them very successfully for one project -- but we had short clips downloaded vis SD cards since at that location we did not have network.

We are thinking of using them on a new project that would require a small window (maybe 128x128 image) captured as fast as we can.. but need to capture for a  moderately long term  (8hrs a day for 50 days). 8hrs at 7500fps of 128x128 is about 1TB but I can download over a network at outside the capture window.  I see 2 ways..  capturing to a large SD card in the camera or a USB SSD in the camera (a 1TB class 10 card should hold 8.6 hours) and then remotely access afterward via SMBor streaming over the network interface and capturing on the computer.  The streaming view over the network says it supports 1920x1080@60fps but I presume that is H264 and I need uncompressed.  Looking through manual I did not see any way to stream uncompressed.. anyone find a a way?  An alternative would be to  save to NSF  but have no idea what sustained rate I could do.   


Can anyone comment on experience with the tradeoffs between long-time SD capture and long-time network capture?  Am what I am describing even possible or I am limited to 32GB of capture then stop recording to dWe have a pair of 2.1 camera and have used them very successfully for one project -- but we had short clips downloaded vis SD cards since at that location we did not have network.

We are thinking of using them on a new project that would require a small window (maybe 128x128 image) captured as fast as we can.. but need to capture for a  moderately long term  (8hrs a day 50 days) and download over a network at outside the capture window.  I see 2 ways..  capturing to a large SD card in the camera (a 1TB class 10 card should hold 8.6 hours) and then remotely access afterward via SMBor streaming over the network interface and capturing on the computer.  The streaming view over the network says it supports 1920x1080@60fps so at 128x128 the data rate seems like we might get 7500fps at the same effective pixel/data rate.


Can anyone comment on experience with the tradeoffs between long-time SD capture and long-time  network capture?  Am what I am describing even possible or I am limited to 32GB of capture then stop recording to transfer/download?