What does the brightness filter do?

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timh
Posts: 680
Joined: Mon Aug 26, 2019 5:50 pm

What does the brightness filter do?

#1

Post by timh »

Hi Robin,

I use this filter but realise that I do not understand what it does exactly. Does it compare the overall contrast or pixel range within frames or literally 'brightness' - but the latter seems unlikely because then cloudy frames that merely reflected suburban light might look bright? I was thinking that relative 'star count' might be useful --but then limited to non planetary stuff

Timh
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Re: What does the brightness filter do?

#2

Post by admin »

Hi Tim,

it monitors the star brightness of detected stars (only looking at those that are not fully saturated I think, otherwise brightness is poorly measured). Anyway, the theory is that if you get thin cloud running through then the star brightness will drop down and the filter can reject those frames until conditions clear again.

https://docs.sharpcap.co.uk/4.0/#Filter ... ess)%20Tab

cheers,

Robin
timh
Posts: 680
Joined: Mon Aug 26, 2019 5:50 pm

Re: What does the brightness filter do?

#3

Post by timh »

Thanks Robin,

That makes sense. I will continue to routinely reject all frames < 80% or so of the first decent one and not worry that I am missing too much.

Tim
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