×

INDI Library v2.0.6 is Released (02 Feb 2024)

Bi-monthly release with minor bug fixes and improvements

Feature request: Close shutter when an artificial satellite is approaching

  • Posts: 152
  • Thank you received: 20
I would like to have this feature once the sky will be full of artificial satellites.
Motivation: Megaconstellations like Starlink will  soon complicate our hobby. It is already complicating it now, but we still can get rid of the satellite traces during stacking. But once there will be 10k+ satellites, it will be really challenging for the rejection algorithms and HW.
Possible solution: A constantly running process, that will automatically shut mechanical shutter of the camera, before a satellite enters Field of view and opens it again when the satellite leaves the FoV. For this to work, a part of the imaging rig must be a scope/camera that has wider FoV. It can be guiding scope/camera or a separate scope/camera setup. This scope/camera will point to the same location as the main imaging scope/camera. Image acquisition speed needs to be quite fast, e.g. 1-10 fps. Every frame will be analyzed in real time and if there is a trace from incomming satellite, it will calculate in which time the satellite will cross (enters and leaves) the FoV of the main imaging scope/camera. During this time, the shutter will be closed and no satellite's trace will be recorded.
Another possible way, how to know, when a satellite will cross the FoV is to have some updated list of possitions of the satellites. I know that this exist, but can not remember the name right now. For this option you don't need wide field scope/camera, but you need online connection to the internet (or at least possibility to download the most recent "satellite list" and then use it offline) is needed.
2 years 8 months ago #73388

Please Log in or Create an account to join the conversation.

  • Posts: 2876
  • Thank you received: 809
This is a good idea in theory, but there are some complications.  One pretty serious issue would be that having the shutter closed for part of the image effectively changes the exposure time.  I guess a solution could be to then keep the camera shutter open by a longer time at the end, but if the camera gets its information about of long the shutter should be open at the beginning of the exposure and does its own timing, then that wouldn’t work, but if the INDI driver does the timing it could work.  I think different cameras do this differently.  Another big issue would be that satellite brightnesses are not constant.  At some hours of the night and at some locations on Earth, satellites are very bright, but at others, the sun doesn’t hit them.  Also some satellites change brightness as they tumble or spin, like iridium satellites did.  So this leads me to think that the best solution might be a wider field monitoring camera.  This is a good idea though and should be considered.
2 years 8 months ago #73405

Please Log in or Create an account to join the conversation.

  • Posts: 152
  • Thank you received: 20
Thank you Rob, so for me it means that it is possible to implement this function. Camera with its own mechanical shutter will benefit from this function. But for cameras without mechanical shutter (and most popular cameras don't have it) it will be needed to have specialized device, that will play role of a mechanical shutter in the optical path. This is a product, that is not on the market now, or at least I don't know if it exist.
2 years 8 months ago #73413

Please Log in or Create an account to join the conversation.

Time to create page: 0.707 seconds