Re: [APML] Equivalent ISO of an ST10E CCD

[Jerry Lodriguss <jml@astropix.com>]

>The pixel value will read higher for the 8 sec exposure than the 1 sec
>exposure. Specifically it will read 8 times higher. If you look at
>Photoshop levels, the "hump" for the 1 sec exposure will be to the left
>of the 8 sec exposure's "hump". I am assuming left is the dark point. In
>both case you have captured the entire "hump", one just has more
>fidelity, i.e. the longer exposure.


Ok, now, what exposure does it take to put the hump exactly in the middle 
of the histogram at level 128?

Jerry

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