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Does anyone know of any (perhaps open source) hardware that's suitable to aim a DSLR-sized camera in a suitable direction with a reasonable kind of precision? I

by tpmx 3y ago

Does anyone know of any (perhaps open source) hardware that's suitable to aim a DSLR-sized camera in a suitable direction with a reasonable kind of precision? I guess medium power (around 10-20W?) BLDC motors combined with hall effect sensors would be suitable for this application since they are used in gimbals? It would be neat to have an auto-aiming and tracking camera with a telephoto lens and record a close-up video of the aircraft instead of a wide angle photo.

dekhn 3y ago
I've done this but for observing the sun with a DSLR/telephoto for long periods. I've seen several projects to do this, a related project is https://opensamofficial.github.io/OpenSAM/ https://opensamofficial.github.io/OpenSAM/ but that's more of a stabilizer. When I built my own I hit a number of challenges: the 3d printed plastic parts melted in the sun (switched from PLA to PETG, printed in pure white). DSLRs with telephotos are heavy so I ended up using gearing. I should have put more time into balancing the camera to reduce the motor demands. I don't think a DSLR is ideal- I'd much rather use a small, cheap industrial camera, but I've never found the equivalent of an affordable 300mm telephoto that is C-mount and goes on industrial camera. I used stepper motors, not BLDC, without feedback (other than a zero-position limit switch) and a simple realtime algorithm for pointing; it worked, but wasn't really good enough to make the sunspot timelapses I wanted. I think for this it makes more sense to buy a quality telescope motorized mount, a nice refractor telescope, and then put a DSLR at prime focus. It'd be about $3K but would save a lot of time compared to DIY.
- tpmx 3y ago
  I didn't think about the heat. Yeah, a DSLR with a decent lens is quite heavy. And expensive, so it needs to be protected. It's a tricky problem to do on the cheap. I don't think I'm prepared to spend $3K, my idea was rather to spend some fun time on HW work as a diversion from the regular paid SW work - and to put some use to that expensive camera gear I'm not really using. Thanks for your lessons learned; they have been helpful!
  - dekhn 3y ago
    Do you have a 3d printer? Spend some time cloning this: https://www.bhphotovideo.com/c/product/689699-REG/Giga_Pan_EPIC_PRO_EPIC_Pro_Robotic_Camera.html https://www.bhphotovideo.com/c/product/689699-REG/Giga_Pan_E... That's what I did. This time around, I'd just buy that.
gavinsyancey 3y ago
Might be worth looking into motorized telescope mounts. Should have plenty of precision, although you might not be able to slew very fast and will probably have to handle zoom/focus/camera control separately. Looks like people have built and documented open-source telescope mounts, or you can buy a cheap one for a couple hundred dollars.
MandieD 3y ago
The steerable rotors amateur radio operators use with large directional antennas might be of interest. The EME (Earth-Moon-Earth) and radio satellite communities in particular have many automated antenna rotation solutions.

by tpmx 3y ago

dekhn 3y ago

I've done this but for observing the sun with a DSLR/telephoto for long periods. I've seen several projects to do this, a related project is https://opensamofficial.github.io/OpenSAM/ https://opensamofficial.github.io/OpenSAM/ but that's more of a stabilizer. When I built my own I hit a number of challenges: the 3d printed plastic parts melted in the sun (switched from PLA to PETG, printed in pure white). DSLRs with telephotos are heavy so I ended up using gearing. I should have put more time into balancing the camera to reduce the motor demands. I don't think a DSLR is ideal- I'd much rather use a small, cheap industrial camera, but I've never found the equivalent of an affordable 300mm telephoto that is C-mount and goes on industrial camera. I used stepper motors, not BLDC, without feedback (other than a zero-position limit switch) and a simple realtime algorithm for pointing; it worked, but wasn't really good enough to make the sunspot timelapses I wanted. I think for this it makes more sense to buy a quality telescope motorized mount, a nice refractor telescope, and then put a DSLR at prime focus. It'd be about $3K but would save a lot of time compared to DIY.

tpmx 3y ago
I didn't think about the heat. Yeah, a DSLR with a decent lens is quite heavy. And expensive, so it needs to be protected. It's a tricky problem to do on the cheap. I don't think I'm prepared to spend $3K, my idea was rather to spend some fun time on HW work as a diversion from the regular paid SW work - and to put some use to that expensive camera gear I'm not really using. Thanks for your lessons learned; they have been helpful!
- dekhn 3y ago
  Do you have a 3d printer? Spend some time cloning this: https://www.bhphotovideo.com/c/product/689699-REG/Giga_Pan_EPIC_PRO_EPIC_Pro_Robotic_Camera.html https://www.bhphotovideo.com/c/product/689699-REG/Giga_Pan_E... That's what I did. This time around, I'd just buy that.

gavinsyancey 3y ago

Might be worth looking into motorized telescope mounts. Should have plenty of precision, although you might not be able to slew very fast and will probably have to handle zoom/focus/camera control separately. Looks like people have built and documented open-source telescope mounts, or you can buy a cheap one for a couple hundred dollars.

MandieD 3y ago

The steerable rotors amateur radio operators use with large directional antennas might be of interest. The EME (Earth-Moon-Earth) and radio satellite communities in particular have many automated antenna rotation solutions.