Found a simple way to fix star trailing without buying a star tracker

I was getting blurry stars in my 30-second exposures on my Canon T7. Tried stacking 5-second subs instead and aligning them in DeepSkyStacker. No more trailing and the detail is way better. Anyone else do short subs for wide field shots?

2 comments

2 Comments

uma_taylor4715d ago

The thing nobody brings up is that shorter subs also help you dodge light pollution better. I shoot from my backyard in a bright orange zone, and stacking 10-second frames lets me clip out the skyglow way more aggressively in post without wrecking the stars. With longer exposures you're filling up those pixels with both light pollution and signal, and it's harder to separate them. I do 8-second subs at ISO 1600 for my 50mm lens and get clean 2-minute stacks. Also helps with saturating those red emission nebulas without blowing out the core of Andromeda or the Milky Way bulge.

janarivera15d ago

Take a look at how many subs you really need to stack before the noise reduction stops helping. I've seen people do 200+ short subs and hit diminishing returns around 60-80 frames. Have you tried testing a 4-minute stack of 8-second subs against a 2-minute stack of 4-second subs? That ratio matters more than people admit. Also, are you dithering between every few frames or just letting the alignment software handle it? Manual dithering makes a shocking difference for me even with those short exposures. My 135mm lens at f/2.8 still shows walking noise if I skip it.