Thread: Perseids 2013
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Old 07-08-2013, 06:49 AM
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sil (Steve)
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Quote:
Originally Posted by JB80 View Post
Does the length of exposure effect the meteors brightness in the picture?
For instance if you had caught the same meteor on a 30 sec exp and the other on a 3 minute one would the build up of the exposure dim the meteor?
No, once the film or sensor has been exposed to a photon it stays "captured" and won't dim if photons are no longer coming from the same spot.

However what you will lose is contrast as the dark areas slowly accumulate more light or image noise. So for example an area of the sky that is black in a 30sec exposure will become lighter in a 3min one, how light depends on conditions and where you are shooting. So as the "background" blackness of space in a widefield shot grows lighter, the meteor stays the same brightness but is now less noticable against the brighter background.

Some meteors are very faint so you probably won't want the background sky to be too light. A longer exposure will give you a better chance of capturing multiples in one shot and steadier (longer) satellite trails (so you don't confuse a short segment of satellite trail as a meteor).
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