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by jbeale
Fri Jul 10, 2020 8:07 pm
Forum: Off topic discussion
Topic: Worst "production" Pi installation
Replies: 17
Views: 568

Re: Worst "production" Pi installation

Nobody thinks some strain relief on those sensor wires hanging off the GPIO pins would be a good idea?
by jbeale
Thu Jul 09, 2020 10:40 pm
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

Today I have received a f=12 mm M12 lens I ordered from 4klens.co over a month ago. It claims to be a 10 MP 1/1.8" format lens, intended for GoPro cameras. It comes with a IR-cut filter on the rear element, which I guess is redundant if used with the Pi HQ camera having its own filter. I added a pho...
by jbeale
Thu Jul 09, 2020 9:21 pm
Forum: General discussion
Topic: scp -p does not preserve full time data?
Replies: 3
Views: 140

Re: scp -p does not preserve full time data?

Very good info, thank you both! Looks like 'rsync' is the answer for me.
by jbeale
Thu Jul 09, 2020 7:27 pm
Forum: General discussion
Topic: scp -p does not preserve full time data?
Replies: 3
Views: 140

scp -p does not preserve full time data?

I can get precise file modification time with apparent nanosecond precision, using 'ls --full-time' : -rw-r--r-- 1 pi pi 1397 2020-06-26 14:22:43.553758892 -0700 Animals-game.txt I can copy this file to another pi, using 'scp -p' to preserve file timestamps: pi@rp49:~ $ scp -p Animals-game.txt pi@rp...
by jbeale
Tue Jul 07, 2020 4:06 pm
Forum: Camera board
Topic: PiKrellCam: motion vector detect + OSD web interface
Replies: 1516
Views: 399102

Re: PiKrellCam: motion vector detect + OSD web interface

I still get some freezes but I think this may be related to something else. I am currently exploring how the GUI preview freezes at sudden changes in light. I am leaning to that many different factors combined cause this. FWIW: I've had good luck running PiKrellCam with v1 and v2 cameras on Pi3 and...
by jbeale
Tue Jul 07, 2020 4:52 am
Forum: Camera board
Topic: Raw sensor access / CSI-2 receiver peripheral
Replies: 640
Views: 206028

Re: Raw sensor access / CSI-2 receiver peripheral

It's an interesting technical problem, but I'm not sure the Pi camera (in raw or normal mode) is the best tool, or even a very feasible one. A tiny high-speed pellet or bb at night is a very difficult thing to photograph, without a huge amount of added light, and if you trigger after impact then you...
by jbeale
Mon Jul 06, 2020 12:58 am
Forum: Camera board
Topic: Raw sensor access / CSI-2 receiver peripheral
Replies: 640
Views: 206028

Re: Raw sensor access / CSI-2 receiver peripheral

You can buy thermal imagers, but they tend to be expensive and there isn't one made for the Raspberry Pi specifically. Also, nothing in the remotely "affordable" category of thermal imagers has enough useful resolution to be able to identify facial features at any distance. The raw mode specifically...
by jbeale
Wed Jul 01, 2020 2:57 pm
Forum: General discussion
Topic: Yesterday, another 3 Pi4Bs 2GB died within 2 hours. Now it's 5 out of 20 dead.
Replies: 54
Views: 3631

Re: Yesterday, another 3 Pi4Bs 2GB died within 2 hours. Now it's 5 out of 20 dead.

Correct me if I am wrong, but it seems to me it only takes one of those stray solder balls to make a (possibly intermittent or temperature-dependent) fault, if for example it gets wedged underneath a BGA part, or trapped between pins in a SD card socket. Is the kind of through-hole pin manual rework...
by jbeale
Sat Jun 27, 2020 11:43 pm
Forum: Camera board
Topic: 16mm lens - fiddly to focus
Replies: 2
Views: 132

Re: 16mm lens - fiddly to focus

I don't have that specific lens but I've experimented with a variety of other lenses, and most of them are very difficult to adjust accurately. The high resolution of the HQ camera makes this more obvious than on lower resolution sensors. I understand it's not the "proper" way, but for small tweaks,...
by jbeale
Mon Jun 22, 2020 2:34 pm
Forum: Camera board
Topic: High Quality Camera IR sensitivity
Replies: 3
Views: 183

Re: High Quality Camera IR sensitivity

I haven't tested the HQ camera, but I've looked at a number of other video cameras. They're all broadly similar. Still useful around 850 nm, low at 940 nm, essentially nothing useful beyond 1000 nm. It's all based on the silicon CMOS detector sensitivity curve. The Bayer-pattern color filter R,G,B d...
by jbeale
Sun Jun 21, 2020 3:26 am
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

Anyone know why this should be true? (running an application using the HQ camera with two video paths, preview & record, a Pi 2 has significantly higher performance than a Pi 4): viewtopic.php?f=43&t=115583&start=1500#p1682869
by jbeale
Wed Jun 17, 2020 10:06 pm
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

That video is from the Pi HQ camera, but I was using a motion-activated program, PiKrellCam configured with a short timeout after initial detected motion. The frame skips are only because that is actually four separate motion-triggered videos, glued together. Re: stepper, yes, with constant loading ...
by jbeale
Wed Jun 17, 2020 5:58 pm
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

Looks like you've got a nice selection of lenses to compare. I'm not sure what "X megapixel" on a lens really means in a technical sense. A chart of the lens MTF (modulation transfer function) across the field, at least has a defined meaning. I suppose the bottom line with any lens test is whether y...
by jbeale
Wed Jun 17, 2020 2:46 pm
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

@jbeale The 17$ lens I did order 6 weeks ago claiming 12MP arrived today: Thank you for that timely post, from the example image that lens looks like a good value! I found a few other f=8mm lenses claiming good resolution, but f=12mm was more difficult to find. My overseas-online shopping experienc...
by jbeale
Wed Jun 17, 2020 2:19 am
Forum: Camera board
Topic: Raspberry Pi High Quality Camera
Replies: 172
Views: 15187

Re: Raspberry Pi High Quality Camera

In case anyone else is looking around for so-called "4k" resolution lenses. I have so far found only one f=12mm M12 lens with reasonably high claimed resolution ("10MP") which was on the "4klens.co" company website. Their contact info says 4K LENS (DBA) Unit 01,10/F,Carnival Commercial BLD, 18 Java ...
by jbeale
Sat Jun 13, 2020 6:57 am
Forum: Automation, sensing and robotics
Topic: Air Quality Monitoring
Replies: 5
Views: 389

Re: Air Quality Monitoring

Sorry I had a typo, the correct name is Plantower PMS5003. You have the correct website for the mfr. I actually bought two, for just under US$20 each shipped to US. My particular vendor doesn't list it anymore, but there are several others on ebay now showing it at a similar price, for example https...
by jbeale
Fri Jun 12, 2020 4:00 am
Forum: Automation, sensing and robotics
Topic: Air Quality Monitoring
Replies: 5
Views: 389

Re: Air Quality Monitoring

I went with the [ EDIT: not Plantronics but] PLANTOWER PMS5003 sensor, which is available under $20 and has tested pretty well against professional PM2.5 sensors. It actually gives you several different measurements at once, including PM1.0, PM2.5, PM10, and a bunch of "greater than" bins starting f...
by jbeale
Thu Jun 11, 2020 8:26 pm
Forum: Camera board
Topic: HQ Camera Sensor Fail with Picamera Not raspistill
Replies: 23
Views: 1105

Re: HQ Camera Sensor Fail with Picamera Not raspistill

The preview comes on, the first image is taken, then I get a runtime error No Data Received From Sensor, check all connections including the SUNNY chip. Obviously it cannot be a connection if the first photo always works. I am running Python3 and did an update and upgrade before running. FWIW your ...
by jbeale
Sun May 31, 2020 5:02 am
Forum: Camera board
Topic: HQ cam: rapid raspistill captures?
Replies: 7
Views: 519

Re: HQ cam: rapid raspistill captures?

https://github.com/raspberrypi/userland/blob/master/host_applications/linux/apps/raspicam/RaspiStill.c#L1059 And 4 lines later it sets the number of buffers. FWIW: My quick-and-dirty test says the stock RaspiStill.c code gives me: encoder_out buffer size = 81920, encoder_out buffer num = 1 by defau...
by jbeale
Fri May 29, 2020 8:12 pm
Forum: Camera board
Topic: HQ cam: rapid raspistill captures?
Replies: 7
Views: 519

Re: HQ cam: rapid raspistill captures?

Thank you 6by9, that suggests there is some hope for better performance. I see that status = mmal_component_create(MMAL_COMPONENT_DEFAULT_IMAGE_ENCODER, &encoder); shows up in https://github.com/raspberrypi/userland/blob/master/host_applications/linux/apps/raspicam/RaspiStill.c#L1035 but is there an...
by jbeale
Fri May 29, 2020 3:51 pm
Forum: General discussion
Topic: Distortion in CSI camera video output
Replies: 13
Views: 612

Re: Distortion in CSI camera video output

A pole might be stiffened with a bracing member, for example. In any case if the camera is vibrating strongly, you may expect difficulties with the image regardless of the specifics of the camera.
camera-pole.jpg
camera-pole.jpg (30.09 KiB) Viewed 424 times
by jbeale
Fri May 29, 2020 2:35 pm
Forum: General discussion
Topic: Distortion in CSI camera video output
Replies: 13
Views: 612

Re: Distortion in CSI camera video output

Looks to me like that camera is vibrating a very large amount: rapidly tilting up and down by what looks like several degrees of angle, if you are using the stock lens. So either the mount is loose, or (for example) it is on a long thin pole and the pole is vibrating or resonating like a bowed strin...
by jbeale
Thu May 28, 2020 8:00 pm
Forum: Camera board
Topic: HQ cam: rapid raspistill captures?
Replies: 7
Views: 519

HQ cam: rapid raspistill captures?

I have now figured out how to get fairly rapid (eg. 4 fps) full-resolution still frames from the HQ camera, using raspividyuv as described here: https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=275363#p1668119 I believe these are strictly speaking video frames from the imaging pipeline's vide...
by jbeale
Thu May 28, 2020 7:38 pm
Forum: Camera board
Topic: HQ cam: convert raspividyuv output to still images ?
Replies: 7
Views: 440

Re: HQ cam: convert raspividyuv output to still images ?

Thank you; indeed ffmpeg does work as you say. (It turns out my low-end 1GB Pi isn't the right choice for this task, but that's a separate thing.)
by jbeale
Thu May 28, 2020 3:38 pm
Forum: Camera board
Topic: HQ cam: convert raspividyuv output to still images ?
Replies: 7
Views: 440

Re: HQ cam: convert raspividyuv output to still images ?

This should be quite similar, I think convert -size 4064x3040 -sampling-factor 4:2:0 -depth 8 yuv:test.yuv -colorspace RGB out%04d.png should work. (I personally would use ffmpeg for the conversion.) Thank you! I confirmed this does work at lower resolutions, eg 640x480. For the full 12MP frame, it...

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