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Old 09-02-2016, 07:43 PM
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RB (Andrew)
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Quote:
Originally Posted by troypiggo View Post
Mind if I ask - Is there a benefit to doing this over Av mode? Why do you need an odd number of flats?
Hi Troy,

It's been years since I've done any astro photography, I'm pushing the old brain to remember, it's been discussed many times on here though I'm sure.

I use P mode and stick to 100 ISO (giving lower noise, better signal) because it initially gives me a histogram close to what I'm after, 1/3 to 1/2 way across.
If it's not close to that I can switch to manual and tweak the setting I got from the P settings to get the ideal histogram.

I use an odd number because I 'median combine' the flats and the 'math algorithm' used in 'median combine' works better with an odd number of frames, from memory.

RB
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