How can I get images from the installed camera on a librem 5? I can get images form a USB camera but that is not rigidly attached to the phone so the gravity and hall sensors cant really be aligned. I am trying to do this all in python if possible. Hopefully this will be a hack that can get us a 500m CAP where a local map would be able to be brought into service for the final navigation.
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Do you mean that you want to automate the capturing of still images from the Librem 5’s built-in camera?
I’m not sure I grasp fully what’s asked, but if you’re looking for the command for taking a camera picture, it’s cam -c1 -C1, if I recall.
sorry for delay, yes I need to get an image from the main camera either a direct access to a /dev/camera0 or I guess maybe a processed image with exact timestamp near realtime could work too, I with best night vision settings to snap stars. I have not worked with cameras like this before and I am expecting the python libs to do the lifting for me.
is it possible to shoot the sun without burning out the sensor or as I suspect just washing out to white when even within a few degrees of the sunlight entering the camera?
You’re asking the camera a lot with those usecases. I’m not sure but in this post there may be something that could help with piping the image more directly: Lib[rem5|camera] to use everywhere - #8 by galilley but the noise ratio of the camera may be a bit much for stars (depending on the quality you want and environmental factors). Astrophotography forums may have better answers.
With sun, prolonged exposure is a risk. I’d get a sun filter and tape it (or do a 3D printed holder that you can slide) into place when taking a sun picture. You’re unlikely to get any details of it without one and even still, with wide angle lens, it’s probably just a small bright dot. Again, astophotography forums and sites have better info available.
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yea I have some welding glass for the sun. really the moon seems to be the best bet as it has a full disc. I was looking for a way to get inertial lnavigation with a way to adjust for the drift factor. maybe it needs a sundial graduated height stick to throw a shadow and the hall sensor since we probably cant directly image the sun.
Not just eye protectors for you or darken filters - I meant proper solar filter meant for cameras, and even a moon filter if you are taking moon shots…
I am on it, I used to make DIY sextants and did sea and air(bubble horizon + altimeter) navigation with them. I have a bit of ANSI shade-12 welding glass Neutral-density filter - Wikipedia cut and uncut which works perfectly for eye protection leaving a easily visible green disc of the sun. Funny thing is it only seems to work during the day and not at night, must be solar powered…
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If the camera is active and you can photograph the sky … then GPS should be working - and you will know exactly where you are - but you would of course need offline maps loaded onto the phone in order to relate your GPS coordinates to a feature in the real world.
So, still struggling to understand the requirement, are you saying that you want to navigate as in the good old days, except with 21st century technology available to you, except intentionally not using the GPS? So intentionally making things difficult?
I don’t know how good the camera will be in capturing night sky images. I think you would need to go somewhere and test that. However these days light pollution is bad even in some rural locations. So you would need to choose your test location carefully.
Edit: PS Would need these damn clouds to go away.
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Realistically this is likely not going to be a useful tech and more of a fun demonstrator. more that I like inertial navigation and celestial navigation and sort of like the effort put into assembling a jigsaw puzzle assembling a somewhat useful navigation program using available sensors is just that a demonstrator that might have a very few niche applications as well as exposing privacy hazards in photography with exact time in the exifs(celestial nav and landmark/terrain matching) or rogue software location tracking using inertial sensors and maybe wifi hotspots to adjust for drift.
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Not to mention, you know, GPS coordinates.
For sure, before sharing a JPEG file with an untrusted party, exiv2 rm foo.JPG
After a few years of not flying I took a refresher course and grabbed some type certifications. The school considered GPS cheating and we had to use and calculate like we were in the 80s with time, gyro, and VOR and NDB radio beacons. I guess I still have a minset that GPS is the last input to check that my work not a primary navigation tool. Also the middle east and southeastern europe have frequently been GPS free zones so I like to test tech that gets us toward any and all fallback alternatives to GNSS where the rest of the tech world relies entirely on that single technology. It is also why I like stuff like bluetooth based viral fidonet messaging solutions or neighborhood LoRa mesh nets. I hate relying on any centralized tech which can be revoked or jammed at will.
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That’s fine. I was just pointing out that an image’s metadata, particularly when captured on a smartphone, will usually contain GNSS coordinates - and that is a blunter privacy hazard than the one you mentioned i.e. no need for landmark / terrain matching, or tricky stuff with time + stars.
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I like your idea, Biketool!! And like you, I like too decentralisation! I’ll be happy to buy your app if you’ll develop it!! Never trust 100% on GPS 
You might be target audience for this: tpikonen/siltamesh: A simple bridge between meshtastic and XMPP - Codeberg.org (maybe the mapping feature can be turned to positioning)
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Hey, biketool, please any update about it?
Are you working on this project?
I’m interested!
Thank you!!
I have something I am working on with stars and sun mapped out, but it is currently back burner until I figure out dumping a readable image from the camera.
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Probably we’ve to wait for PureOS Dawn to have a working camera and readable pictures (hope so 
)
Firstly for GPU GLES3 working..