Chronos 4K12 high speed camera teardown  - Page 1
Forum section: electronics / testgear

author: tesla500
author_rank: Regular Contributor
timestamp: November 15, 2023, 04:05:42 am
content: Here's an overview and teardown of my new high-speed camera, the Chronos 4K12The Chronos4K12andQ12are self-contained high speed cameras capturing video at a rate of 12 gigapixels per second. They're based on the GSPRINT4510 and GSPRINT4521 sensors from Gpixel, and a Zynq ZU7EV FPGA/SoC.Here's the frame rate table showing rates at common resolutions:I'm happy to do an AMA if anyone has questions on the camera, it's development/history, how the team and I got from the original cameras to these new ones, etc.Cheers!David/tesla500

author: Dan123456
author_rank: Regular Contributor
timestamp: November 15, 2023, 07:17:25 am
content: Thank you so much for thisI barely understood half it but I find high speed photography/ videography absolutely fascinating!Blows my mind how quickly the field seems to be moving (at least from a layman’s perspective) and absolutely can not wait to see current cutting edge tech move in consumer products in the next ~10 years or what notAppreciate you and the teams workEdit: Forgot to say, I love the cat noises in the background

author: Psi
author_rank: Super Contributor
timestamp: November 15, 2023, 08:07:54 am
content: Interesting that the 1.4 can do a double the framerate (40k) at lower resolutions than the newer cameras (20k).Probably a trade off when using off-the-shelf ram/ssd, or maybe the 2k/4k camera sensors are slower even at low res. dunno.Probably orders of magnitude smaller market for ultra high FPS at low res, verses 2k/4k resolution.Likely higher profits per unit though.I imagine the really high FPS (100-500kFPS) requires massively striped memory arrays, so quite a different beast.

author: tesla500
author_rank: Regular Contributor
timestamp: November 15, 2023, 08:53:36 pm
content: Quote from: Dan123456 on November 15, 2023, 07:17:25 amThanks so much!Quote from: Psi on November 15, 2023, 08:07:54 amThe newer sensors are much more parallelized, the GSPRINT4521 has an ADC on each pixel column, top and bottom, for 10,240 ADCs operating at ~2MSa/s each. The LUX1300 in the Chronos 1.4 has 16 ADCs at 90MSa/s with multiplexers to select which columns and rows they are reading, so they do better windowing (tradeoff of resolution for speed). What's not shown in the chart is that the new cameras can do those highish (~20kFPS) rates with X widths up to about 1500 pixels, with no speed penalty, due to the column parallel ADCs.Companies like Phantom have pretty much completely exited the low end market because of us, they only do ultra high frame rate cameras now. That's where I want to get eventually but it is expensive to have custom silicon made...Those ultra-high frame rate cameras usually use several FPGAs in parallel, using the RAM kind of like a RAID array to handle the higher pixel rates.

author: thm_w
author_rank: Super Contributor
timestamp: November 16, 2023, 12:22:01 am
content: Incredible work as always.With the USB-C lacking internal battery is probably not much of an issue. Maybe you could sell a mount or bracket to hold a battery bank, if any customers actually needed it (like the ethernet thing). Makes it way easier to ship too.How many layers for the FPGA PCB?Have you tested at 40C+ in a chamber yet to see where it overheats/doesnt blow up? (spec is listed at 0C to 40C).

author: tesla500
author_rank: Regular Contributor
timestamp: November 16, 2023, 05:21:56 am
content: Quote from: thm_w on November 16, 2023, 12:22:01 amYes there will be a kit with a cage and brackets designed to hold external batteries and a more ergonomic handle.Quote from: thm_w on November 16, 2023, 12:22:01 amThe main board is 18 layer.Quote from: thm_w on November 16, 2023, 12:22:01 amThe camera has passed thermal testing at 40C ambient, the fans get loud but it doesn't overheat at all. The amount we can slow down the fans to keep it quiet is limited moreso by the temperature of the case than the internal components, the case gets too hot to comfortably hold well before anything overheats.David

author: magic
author_rank: Super Contributor
timestamp: November 16, 2023, 08:34:46 pm
content: 1280x96 looks like a typo

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 16, 2023, 11:31:26 pm
content: Excellent work again guys!Quote from: magic on November 16, 2023, 08:34:46 pmHow so? You didn't think the framerate on that row was a typo, didja?Tim