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Roll Your Own All-Sky, Raspberry Pi Camera

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Re: Roll Your Own All-Sky, Raspberry Pi Camera

#11

Post by giantrobot »

geerlingguy wrote: post #9
ShadowBanThis01 wrote: post #5

Earlier quoted context omitted.

Thanks. I guess at some point the value proposition is antithetical to that of the Pi itself...

Yeah the problem is optics (the more important part of getting really good images) are expensive, and few companies make decent lenses that target tiny sensors. So you're stuck with the little optics included with the tiny hobby cameras from Pi or ArduCam (et all). They're okay for some purposes but a lot worse than even a cheap SLR/Mirrorless lens. The best results I've gotten are with the C-mount camera module, an…

Thrift/antique stores are a place to look for old lenses on the cheap. If you've got a C-mount adapter for your sensor you can mount the lens on it. Then you can manually focus it and epoxy it on the right point.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#13

Post by wkat4242 »

ShadowBanThis01 wrote: post #3

Is there a MIPI camera that doesn't suck? I have every official Pi camera, and they are all just terrible. I would never use them for anything artistic, when it's easy to get far-superior results from even a cheap regular camera or used SLR. I'm just curious if there's a very-high-quality camera with a MIPI interface. Thinking it through... I only really care about video. Even if it's only HD resolution, something wi…

They suck at video. Take stills and they do a lot better.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#15

Post by TheSpiceIsLife »

wkat4242 wrote: post #12
porphyra wrote: post #7

How do you prevent the sun from damaging the sensor over time?

I've had a pi 1 camera looking out at the horizon for many years and it didn't really get damaged. Don't forget the default lens is tiny. It doesn't really capture a ton of light.

If you know the diameter of the lens, and your areas insolation, you could work out it's annual solar energy exposure in watts yeah.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#16

Post by jws »

Having done this…

- don’t make your camera the highest thing around. My dome was showing scratches. Eventually I got a nice photo of the inside of a juvenile bald eagle’s talon. A bird’s gonna perch where a bird’s gonna perch. Sacrifice some sky and put a better perch next to it.

- the manual focus cameras seem to be temperature dependent. Maybe get something that can be auto focused or add a heater to control night time lows.

- for long exposure low light work, you may find you get much better pictures in very cold weather. This relates to charge leakage in the sensor. If you decide to try keeping your sensor cold, consider condensation. Maybe have something in there that is colder.

- also for long exposures, the noise in the image from leakage tends to be device pixel specific. You can make a dark view map at a given temperature and use it to denoise your images. You’ll need a shutter though, or do something clever with multiple frames as stars move around to get “darkest sample” or something

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#17

Post by jws »

wkat4242 wrote: post #12
porphyra wrote: post #7

How do you prevent the sun from damaging the sensor over time?

I've had a pi 1 camera looking out at the horizon for many years and it didn't really get damaged. Don't forget the default lens is tiny. It doesn't really capture a ton of light.

I had one pointed east at the horizon the show a lighthouse a mile away using an old spotting scope. Worked ok until the sun made its way around to rise in frame. Now everything is greenish. I think with sufficient magnification you can cook your color filters or maybe the sensor wells under the filters.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#18

Post by ShadowBanThis01 »

geerlingguy wrote: post #9
ShadowBanThis01 wrote: post #5

Earlier quoted context omitted.

Thanks. I guess at some point the value proposition is antithetical to that of the Pi itself...

Yeah the problem is optics (the more important part of getting really good images) are expensive, and few companies make decent lenses that target tiny sensors. So you're stuck with the little optics included with the tiny hobby cameras from Pi or ArduCam (et all). They're okay for some purposes but a lot worse than even a cheap SLR/Mirrorless lens. The best results I've gotten are with the C-mount camera module, an…

I have the C-mount module and a Canon security-camera lens with zoom, focus, and aperture settings. Disappointingly, it still sucks.

I know there are excellent C-mount lenses, because I shot a great-looking movie on a Bolex with them.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#19

Post by gmiller123456 »

The Pi cameras might seem like a good choice because they're cheap, and might be a good way to start. But with all of the work required to build, install, and maintain one, the cost of the camera is a drop in the bucket. I used a much better camera from ZWO (ASI462MC) for about $300 (I actually ended up building a second one with the ASI462MM (monochrome)). It even comes with an all sky lens. IMHO it doesn't make a lot of sense to cheap out on the camera with all the effort involved in building one. I also needed to add a short length of Nichrome wire (1amp at 12v) to fight condensation.

I started with the color camera, but had to give up on any real meteor detection due to the amount of light pollution, and the fact that I live directly in line with the airport in Louisville. I built the second monochrome version, since the monochrome versions are roughly 3x as sensitive, hoping it'd be better at detecting meteors at shorter exposure lengths. But it still required exposures of a few seconds, much longer that you're typical meteor. So, now I just have two all sky cameras doing 20 second exposures. The monochrome one will still pull out the Milky Way from my Bortle 7/8 skies, so I just like the pictures it takes and don't plan to change it.

Re: Roll Your Own All-Sky, Raspberry Pi Camera

#20

Post by fludlight »

jws wrote: post #16

Having done this… - don’t make your camera the highest thing around. My dome was showing scratches. Eventually I got a nice photo of the inside of a juvenile bald eagle’s talon. A bird’s gonna perch where a bird’s gonna perch. Sacrifice some sky and put a better perch next to it. - the manual focus cameras seem to be temperature dependent. Maybe get something that can be auto focused or add a heater to control night…

> Maybe have something in there that is colder

Such as?

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