Vent: Spent years stacking photos wrong after a talk at the Griffith Observatory

I was at a talk at the Griffith Observatory 2 years back, and the speaker showed how he layers his deep-sky images. Turns out I had been stacking my nebula shots with the wrong calibration frames the whole time, just using darks and not bias frames. A guy next to me pointed out my Andromeda shot had a gradient from the sensor noise I wasn't removing. Anyone else realize they were skipping a calibration step for way too long?

3 comments

3 Comments

taylor.brooke1mo ago

Bought a whole set of bias frames thinking I was extra fancy.

rowan_ross1mo ago

I used to think spending money on bias frames was kind of a waste, that you could just take them yourself whenever you needed them. But honestly, after buying a set once from a reputable source, I realized I was getting way more consistent data, especially for those super dim targets where every little noise reduction counts. Your flat frames might also look cleaner too because the bias subtraction step just works better. Now I'm kind of a convert and see why people drop money on pre-made sets.

viola_garcia561mo ago

Paying for bias frames seems like a waste of money when you can take your own in a few minutes. A set made by someone else using a different camera or even a different temperature is probably not going to match your sensor's exact noise pattern anyway. Sounds like a way to burn cash on something that's basically free to make yourself if you just follow the right steps.