ajacocks
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Joined: Thu May 14, 2020 3:26 pm

Re: Raspberry Pi High Quality Camera

Thu May 14, 2020 3:28 pm

Does anyone know the dimensions of the back focus lock screw? My HQ camera module came without the screw, and I'd like to be able to lock down the back focus distance.

Thanks!
- Alex

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HermannSW
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Re: Raspberry Pi High Quality Camera

Mon May 18, 2020 8:03 pm

For my raspcatbot 0.3MP monochrome global shutter camera I need to determine mapping of 3D world coordinates to 2D screen coordinates and vice versa:
Image


I will use OpenCV calibrateCamera() function for that. The simple use of OpenCV sample program calibrate.py is described here:
https://opencv-python-tutroals.readthed ... ation.html

More details on returned parameters as well on the math can be found here:
https://docs.opencv.org/2.4/modules/cal ... ction.html

I decided to test with HQ camera first, because the CS lens I use has quite some distortion.
I took a first set of 12 images and used them with calibrate.py.
This was the resulting matrix and other data (RMS=Root Mean Square):

Code: Select all

RMS: 9.527956154316893
camera matrix:
 [[1.35899311e+05 0.00000000e+00 1.68280517e+03]
 [0.00000000e+00 2.13924691e+04 1.77160419e+03]
 [0.00000000e+00 0.00000000e+00 1.00000000e+00]]
distortion coefficients:  [-3.31824847e+01  1.90620833e+03 -1.70991694e-01  7.92323636e-02
  1.12371888e+01]

I executed calibrate.py on same set of chessboard images again and got the exact same result.
So the algorithms seem to be deterministic, although code gets executed in 4 threads.
Nice to see "python" running with 392% CPU on the Pi4B.

Next I took a better set of 14 chessboard test images, only in 3 of them the algorithm was not able to identify the chessboard. I expected to get different values, but not that different (I did not touch camera nor lens, just moved the chessboard pattern, "6x9" in code):

Code: Select all

RMS: 3.7905652477411738
camera matrix:
 [[2.63019359e+03 0.00000000e+00 2.08823155e+03]
 [0.00000000e+00 2.62418212e+03 1.62201624e+03]
 [0.00000000e+00 0.00000000e+00 1.00000000e+00]]
distortion coefficients:  [-0.4660976   0.2463531  -0.00352397 -0.00196078 -0.06518195]
Much better RMS, and focal lengths fx=2630px and fy=2624px.

Form the source image a same format "_chess" image gets created, and the determined pattern gets drawn with color lines. This is 12MP photo scaled to15%:
07_chess.15%.jpg
07_chess.15%.jpg
07_chess.15%.jpg (60.56 KiB) Viewed 831 times

For every "_chess" image an "_undistorted" image gets computed, in which straight lines in real world are straight lines as well. This is generated image scaled to 40% of its (smaller than 12MP) size:
07_undistorted.40%.jpg
07_undistorted.40%.jpg
07_undistorted.40%.jpg (73.09 KiB) Viewed 831 times

P.S:
Animation allows to better "see" the transformation:

Code: Select all

🍓 ls -l a??.jpg
lrwxrwxrwx 1 pi pi 16 May 19 07:14 a01.jpg -> 07_chess.15%.jpg
lrwxrwxrwx 1 pi pi 22 May 19 07:21 a02.jpg -> 07_undistorted.40%.jpg
🍓 ffmpeg -r 1 -i a%02d.jpg z.anim.gif
ffmpeg version 4.1.4-1+rpt7~deb10u1 Copyright (c) 2000-2019 the FFmpeg developers
...
video:228kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.350266%
🍓 ls -l z.anim.gif 
-rw-r--r-- 1 pi pi 234068 May 19 07:24 z.anim.gif
🍓 
z.anim.gif
z.anim.gif
z.anim.gif (228.58 KiB) Viewed 743 times
Last edited by HermannSW on Tue May 19, 2020 5:26 am, edited 1 time in total.
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xkubazz
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Re: Raspberry Pi High Quality Camera

Mon May 18, 2020 11:23 pm

Last week I tested HQ Camera with subjects both very far and very close, enjoyed both.

Up is Leo Triplet using Tair-3 300/4.5 lens, 60 minutes total exposure time
Below is my hair through CZJ Flektogon 35/2.4 with 7cm extension tube. 7cm is a bit long for this lens, but with 3,5cm I can get pinpoint sharpness and 1,5:1 magnification

Overall, I'm having a blast with this little camera and cannot wait to use it more.
I got tons of valuable information from this forum, thank you all.

Image

I only wish there was a way to disable noise reduction, but as far as I know Sony does this on most of their modern sensors (including high end full frame mirrorless cameras) and it is really a shame (on Sony, not on RPi devs!)

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Zulu0001
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Re: Raspberry Pi High Quality Camera

Tue May 19, 2020 12:56 am

I am very new to camera's and lenses. I've ordered the new HQ camera module. Does anyone have a recommendation for a 5-50 mm zoom lens for under $100.00. I'd like use it for taking pictures of 3D printed miniatures.

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HermannSW
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Re: Raspberry Pi High Quality Camera

Tue May 19, 2020 4:48 am

6by9 wrote:
Wed May 13, 2020 2:39 pm
Correct, the number isn't delivered back to the app, only scribbled on the images.
(Using libcamera and the vc.ril.isp or V4L2 isp component you do get back the raw FOM statistics)
Does v4l2-ctl allow to query FoM statistics?
If so, how?
From /dev/video12?

Code: Select all

$ dmesg
...
[    4.948458] bcm2835-codec bcm2835-codec: Device registered as /dev/video10
[    4.948498] bcm2835-codec bcm2835-codec: Loaded V4L2 decode
[    4.958079] bcm2835-codec bcm2835-codec: Device registered as /dev/video11
[    4.958112] bcm2835-codec bcm2835-codec: Loaded V4L2 encode
[    4.964967] bcm2835-codec bcm2835-codec: Device registered as /dev/video12
[    4.965005] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
...
https://stamm-wilbrandt.de/en/Raspberry_camera.html
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/raspiraw
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/github_repo_i420toh264

naushir
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Re: Raspberry Pi High Quality Camera

Tue May 19, 2020 9:12 am

HermannSW wrote:
Tue May 19, 2020 4:48 am
6by9 wrote:
Wed May 13, 2020 2:39 pm
Correct, the number isn't delivered back to the app, only scribbled on the images.
(Using libcamera and the vc.ril.isp or V4L2 isp component you do get back the raw FOM statistics)
Does v4l2-ctl allow to query FoM statistics?
If so, how?
From /dev/video12?

Code: Select all

$ dmesg
...
[    4.948458] bcm2835-codec bcm2835-codec: Device registered as /dev/video10
[    4.948498] bcm2835-codec bcm2835-codec: Loaded V4L2 decode
[    4.958079] bcm2835-codec bcm2835-codec: Device registered as /dev/video11
[    4.958112] bcm2835-codec bcm2835-codec: Loaded V4L2 encode
[    4.964967] bcm2835-codec bcm2835-codec: Device registered as /dev/video12
[    4.965005] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
...
Using libcamera, yes you can access the raw focus stats.

You need to queue/dequeue buffers on /dev/video16 (the ISP statistics output node). The statistics will be in the format given by the kernel UAPI:
https://github.com/raspberrypi/linux/bl ... isp.h#L284

Note, our ibcamera pipeline handler already queues/dequeues statistics buffers, so it might be worth a look in that codebase if you don't want to reinvent everything.

6by9
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Re: Raspberry Pi High Quality Camera

Tue May 19, 2020 9:13 am

HermannSW wrote:
Tue May 19, 2020 4:48 am
6by9 wrote:
Wed May 13, 2020 2:39 pm
Correct, the number isn't delivered back to the app, only scribbled on the images.
(Using libcamera and the vc.ril.isp or V4L2 isp component you do get back the raw FOM statistics)
Does v4l2-ctl allow to query FoM statistics?
If so, how?
From /dev/video12?

Code: Select all

$ dmesg
...
[    4.948458] bcm2835-codec bcm2835-codec: Device registered as /dev/video10
[    4.948498] bcm2835-codec bcm2835-codec: Loaded V4L2 decode
[    4.958079] bcm2835-codec bcm2835-codec: Device registered as /dev/video11
[    4.958112] bcm2835-codec bcm2835-codec: Loaded V4L2 encode
[    4.964967] bcm2835-codec bcm2835-codec: Device registered as /dev/video12
[    4.965005] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
...
rpi-5.4.y kernel.
You'll have /dev/video13 to /dev/video16. 13 is the input, 14 is the high res output, 15 is the low res output, and 16 is the stats output.

The format of the stats is as documented in https://github.com/raspberrypi/linux/bl ... -stats.rst and the struct at https://github.com/raspberrypi/linux/bl ... isp.h#L310
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HermannSW
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Re: Raspberry Pi High Quality Camera

Tue May 19, 2020 9:58 am

6by9 wrote:
Tue May 19, 2020 9:13 am
rpi-5.4.y kernel.
You'll have /dev/video13 to /dev/video16. 13 is the input, 14 is the high res output, 15 is the low res output, and 16 is the stats output.

The format of the stats is as documented in https://github.com/raspberrypi/linux/bl ... -stats.rst and the struct at https://github.com/raspberrypi/linux/bl ... isp.h#L310
Thanks, very interesting.
I lost my "rpi-update"d 5.4 kernel SD card (*), will find another, install Buster and do rpi-update again to get 5.4 kernel.

https://github.com/raspberrypi/linux/bl ... isp.h#L317
* @focus_stats: Focus filter statistics for the focus regions.

Code: Select all

🍓 userland/build/bin/raspistill | grep -i focus
-fw, --focus	: Draw a window with the focus FoM value on the image.
🍓 
Are these stats always available, or only when raspistill started with "--focus"?
Is it always one focus area, unchangeable?
Or can different focus areas be specified?


(*)
My son studying computer science (master) is home since two weeks because of COVID-19.
He works as student assistant at a robotic institute for more than 1.5 years.
Most of their robots are controlled via ROS on Ubuntu.
So he took my 2GB Pi4B, installed Ubuntu and ROS and will control caterpillar robot platform with Hall sensor motors via ROS, which I use for my raspcatbot (the hall sensor motors are rated 9V 150rpm, the ones I use for raspcatbot are rated 12V 1500rpm):
viewtopic.php?f=37&t=267999&p=1643242#p1643665
Image
https://stamm-wilbrandt.de/en/Raspberry_camera.html
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/raspiraw
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/github_repo_i420toh264

CanPi
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Re: Raspberry Pi High Quality Camera

Wed May 20, 2020 4:57 pm

xkubazz wrote:
Mon May 18, 2020 11:23 pm

Image

I only wish there was a way to disable noise reduction, but as far as I know Sony does this on most of their modern sensors (including high end full frame mirrorless cameras) and it is really a shame (on Sony, not on RPi devs!)

Nice, skubazz! May I ask what script/settings were used for the sky image?

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jbeale
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Re: Raspberry Pi High Quality Camera

Wed May 20, 2020 7:58 pm

Zulu0001 wrote:
Tue May 19, 2020 12:56 am
I am very new to camera's and lenses. I've ordered the new HQ camera module. Does anyone have a recommendation for a 5-50 mm zoom lens for under $100.00. I'd like use it for taking pictures of 3D printed miniatures.
I cannot answer the question because I don't have a recommendation, although I do have an anti-recommendation. I have a lens that looks exactly like, and likely is this one https://www.ebay.com/itm/Manual-IRIS-Zo ... 3035602814
and it is probably OK for a 5Mpix camera on the wide end, but it is *awful* on the long end at any aperture setting. So I suggest don't get that one.

xkubazz
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Re: Raspberry Pi High Quality Camera

Thu May 21, 2020 6:23 pm

CanPi wrote:
Wed May 20, 2020 4:57 pm
Nice, skubazz! May I ask what script/settings were used for the sky image?

Code: Select all

time ~/userland/build/bin/raspistill --mode 3 --exposure verylong --shutter 30000000 -t 3600000 --ISO 100 --awb off --analoggain 1.0 --digitalgain 1.0 --raw --timelapse 500 --nopreview --burst -o leo_%04d.jpg
30 second exposures over 1 hour.

I used raspistill compiled from sources a few days ago, but there have been some updates since to disable initial calibration, check this thread.

For extracting RAWs I used fork of dcraw from 6by9's github:

Code: Select all

for f in *.jpg ; do ~/dcraw-master/dcraw -T -6 -W -r 3.0 1.0 1.49 1.0 -g 1 1 /[path-to-your-pictures]/$f ; done
This will extract RAW data from all JPEGs in given folder, apply basic white balance, and convert them to 16-bit linear TIFF files.

Then I stacked those images using Deep Sky Stacker and did post-processing in Lightroom.

edit: Okay, after running rpi-update, apt-get upgrade and apt-get update following works and properly skips initial calibration:

Code: Select all

raspistill --mode 3 --exposure off --shutter 30000000 -t 3600000 --ISO 100 --awb off --analoggain 1.0 --digitalgain 1.0 --raw --timelapse 500 --nopreview --burst -st -o leo_%04d.jpg

CanPi
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Re: Raspberry Pi High Quality Camera

Fri May 22, 2020 7:05 am

Excellent, thank you. Just out of curiosity, what happens if the -ISO and -st switches are dropped? I would think you'd have less of a possibility of the drivers messing with gains.

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Re: Raspberry Pi High Quality Camera

Fri May 22, 2020 7:29 am

CanPi wrote:
Fri May 22, 2020 7:05 am
Excellent, thank you. Just out of curiosity, what happens if the -ISO and -st switches are dropped? I would think you'd have less of a possibility of the drivers messing with gains.
-ISO only does anything if -ex is NOT off, and it controls analogue and digital gains. Seeing as there is already "--analoggain 1.0 --digitalgain 1.0" parameters in there, then it's going to do nothing.

-st allows the tuners to run on the input image, and then reprocesses the input image to make the final output image.
AE and AWB should be doing nothing if you have set them to off or otherwise removed their degrees of freedom (-ss, -ag, and -dg), but there's also the lens shading algorithm running. If you haven't provided your own lens shading table then you probably want that.
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HermannSW
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Re: Raspberry Pi High Quality Camera

Fri May 22, 2020 9:40 am

> -ISO only does anything if -ex is NOT off,
>
I tried to capture stars last night in garden with the command from long exposure thread:
viewtopic.php?f=43&t=273358&p=1664566#p1664566

What I got was nearly dark, but then adding "-ISO 800" did at least show garden house on left side and bush on right side a bit.
Since the long exposure command did contain "-ex off", how can adding ISO have had an effect?
https://stamm-wilbrandt.de/en/Raspberry_camera.html
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/raspiraw
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kevin140473
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Re: Raspberry Pi High Quality Camera

Fri May 22, 2020 11:56 am

spidermanman wrote:
Tue May 05, 2020 9:24 pm
Is anyone else having issues using Picamera with the new HQ camera? Mine times out when I take still captures.
Similar issue. Using PiCamera capture times out after the first image. To get around this I have had to set 'use_video_port=True'

Anyone else can assist?

UPDATE: Pi firmware required an update. After updating RPI3B PiCamera captures images.
Last edited by kevin140473 on Sat May 23, 2020 3:07 pm, edited 1 time in total.

xkubazz
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Re: Raspberry Pi High Quality Camera

Fri May 22, 2020 9:31 pm

HermannSW wrote:
Fri May 22, 2020 9:40 am
> -ISO only does anything if -ex is NOT off,
>
I tried to capture stars last night in garden with the command from long exposure thread:
viewtopic.php?f=43&t=273358&p=1664566#p1664566

What I got was nearly dark, but then adding "-ISO 800" did at least show garden house on left side and bush on right side a bit.
Since the long exposure command did contain "-ex off", how can adding ISO have had an effect?
I tested this and also confirm that --ISO will override analog gain with --exposure off.

It also turned out that I made a mistake by setting analog gain to 1.0 for astrophotography, read noise of this sensor is actually quite noticeable and you should be going for high analog gain for better SNR, as long as parts of image don't get overexposed.

0.5s exposures, Peltier cooler attached and fan running to keep sensor temperature stable. Captured RAWs and matched exposures in postprocessing.
Image


Even at 30 seconds per exposure there is noticeable difference in noise level. I honestly expected thermal noise to overpower read noise by orders of magnitude at such long exposure time, but I was wrong.
Image

CanPi
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Re: Raspberry Pi High Quality Camera

Sat May 23, 2020 6:28 am

Good demo. FYI analog gain actually goes up to 16 in the HQ.

billgs
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Re: Raspberry Pi High Quality Camera

Sat May 23, 2020 6:53 am

Waiting for the rpi-update I used V3 on a 80 mm refactor telescope to do
similar time-lapse exposures to those I had made with V2s. Settings such as
raspistill -t 30000 -ex night -ISO 800 -bm -tl 0 -o timelapse1%d01.jpg
were used with -ss varied between 5000000 and 30000000. I found that, for example,
with -ss at 20000000 and after a wait of around 1min 20 secs, two images at
10.3 secs were produced followed by 20sec images for as long as -t allowed.

20 secs was the maximum image length achieved but variation of ISO did cause image
change up to 800. Is there a set range of ISO for camera V3?

I did the rpi-update (my thanks to all concerned) and did some
measurements with the stated settings which checked out as expected. I noted
that ISO was reported at 6 and could not be increased which could be a limitation
for astrophotography.

I then input:-
raspistill -t 600000 -bm -ex night -ISO 6 -tl 0 -ss 60000000 -o 22mayclocka%d01.jpg
(note: no -md 3) and saw, after a wait of about 1min 20sec two 10.3 sec images
followed by a series of 7 60sec images as indicated by EXIF.

I will set up an analogue clock to do a series of measurements to confirm the EXIF data.
The measurements so far confirm that maximum exposure is 240seconds.

I will also check to see if ISO can be varied.

I use WNinSCP to monitor the RPi output and pass the images to XnView for EXIF
readings etc..

RoboRob
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Re: Raspberry Pi High Quality Camera

Sat May 23, 2020 1:13 pm

I've tested a the new HQ camera a lot i.c.w a (small) telescope. This command should give you an exposure of 60 seconds but you should be able to go up to 200 sec (-ss 200000000):

Code: Select all

raspistill --nopreview --metering average --thumb none --raw --quality 100 --output image_1_60000000_1x1_20200522T180944.jpg --exposure off --flicker off --awb off --awbgains 2,1.53 --shutter 60000000 --drc off --analoggain 1 --mode 3 --timeout 3000 --digitalgain 1 --stats --burst
If you want long exposures make sure to set the --stats, --burst and --analoggain [value] parameters and set --exposure off to limit the capture and download times (need since the latest updates of May 19th for short process times)...

BTW don't use ISO, just set the analog gain (1 - 16 (I though it only went up to 12 but in this thread 16 is mentioned)).

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HermannSW
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Re: Raspberry Pi High Quality Camera

Sat May 23, 2020 2:51 pm

billgs wrote:
Sat May 23, 2020 6:53 am
I will set up an analogue clock to do a series of measurements to confirm the EXIF data.
The measurements so far confirm that maximum exposure is 240seconds.
Please confirm, according docs it is 200s (and I assume that 240s shutter time argument will be capped to 200s).

6by9 used (1500€) Image Engineering LED-panel for such confirmation:
viewtopic.php?f=43&t=273358&p=1664566#p1664463

Motivated by that, I used <5$ diy solution (1.40$ 8x8 dot matrix LED, 3$ Arduino Uno R3 clone) for that.
My Arduino sketch lights 1 led at a time for 3.333s, rows from top to bottom, from left to right.
200s/3.333s=60.006, so 3 leds remain unlit, room was completely dark:
viewtopic.php?f=43&t=273358&p=1664566#p1664566
Image
https://stamm-wilbrandt.de/en/Raspberry_camera.html
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/raspiraw
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/github_repo_i420toh264

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jbeale
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Re: Raspberry Pi High Quality Camera

Mon May 25, 2020 10:56 pm

In case anyone else is interested in longer lenses, I came across a "PixAero" brand f=25mm, f/2.8, M12 mount lens that claims 4k or 12Mpixel resolution and 20 degree HFOV. https://www.ebay.com/itm/25-mm-DUO-Manu ... 3537670923

This is intended for a YI 4k "action cam" using a Sony IMX377 sensor in the same 1/2.3" format size as the IMX477. You would need a M12 to C/CS lens adaptor for the Pi-HQ cam, but those are cheap.

The listing links an example video, in macro mode with insects https://www.youtube.com/watch?v=36VwhKezXBM but that is for a wide-angle, f=3.77 mm lens from the same company, not using this particular lens.

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HermannSW
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Re: Raspberry Pi High Quality Camera

Tue May 26, 2020 12:18 am

HermannSW wrote:
Sat May 23, 2020 2:51 pm
billgs wrote:
Sat May 23, 2020 6:53 am
I will set up an analogue clock to do a series of measurements to confirm the EXIF data.
The measurements so far confirm that maximum exposure is 240seconds.
Please confirm, according docs it is 200s (and I assume that 240s shutter time argument will be capped to 200s).
By calculations done on I2C capturing of 200s raspistill long exposure I was pretty sure that 239s are possible:
viewtopic.php?f=43&t=109137&p=1666826#p1666758

I remembered that you stated that 240s is possible with raspistill.
I did reprogram the Arduino to light each 8x8 matrix display dot for now 4 seconds.
And I did capture with the command shown before, but this time with 239s shutter time.
239s/4s=59.75, therefore 4 dots remain unlighted, and that is really the case (room was completely dark):
long_exposure_239s_d.15%.jpg
long_exposure_239s_d.15%.jpg
long_exposure_239s_d.15%.jpg (81.16 KiB) Viewed 27 times

Summary:
raspistill (after rpi-update) allows for 239s(!) long exposures.
Documentation needs to be corrected.
https://stamm-wilbrandt.de/en/Raspberry_camera.html
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/raspiraw
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://stamm-wilbrandt.de/github_repo_i420toh264

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