4 ms·
One benefit of shoot-move-shoot is that when combining/compositing the images together in post, you can remove and adjust for temporary artifacts like satellite
by LeifCarrotson 5y ago
One benefit of shoot-move-shoot is that when combining/compositing the images together in post, you can remove and adjust for temporary artifacts like satellites or terrestrial lighting that would otherwise ruin a long exposure. You can also compensate for motion platform inaccuracies by shifting the location of each layer to keep the object you're trying to image at the same location in the frame. Minutes-long exposures mean you're just ORing all the photons together, and you get what you get.
- astroflask 5y agoFor sufficiently dim targets, you absolutely need minutes long exposure. If you go for shorter bursts, you face two main challenges: 1) Not enough photons reach the sensor to distinguish the object you are trying to photograph from the noise floor of the sensor. This is by far the biggest reason to go for a tracking mount. 2) You bog your computer down in post processing. 50x1 minute images are far simpler to align than 500x6 seconds images. Combine (1) and (2), and there's barely any reason to go for untracked shots. As for satellites, planes, clouds, or other kind of transient phenomena that can potentially ruin a shot, that's where you apply some kind of clipping over data (usually sigma clipping or some variation of it) and problem solved.