Hello,


I am trying to make night shots with a ccd camera.
The maximum exposure time that can be set on the camera is 750 ms, which
is of course too short.

Assuming the noise is random and the object I want to see does not move,
I should be able to improve signal-to-noise by taking the same shot
several times and  adding all the  images together (using an iterative
shell script which adds each successive image to the "sum" image,
starting from a black image with the correct size and depth): the noise
should "cancel out" and the signal should accumulate.
As adding many layers of noise will eventually saturate the image, I
decided to use the quantum:format=floating-point option.(support is
compiled in) and I save to the "miff" format.

Now for the questions:
- is it correct that both the "display" and the "identify" programs  and
the "histogram" option of convert have trouble handling this
floating-point format?
- supposing the adding worked fine, what would be the best way to
convert the result to a "normal" image for viewing on the screen (8 bits
per channel) while preserving as much information/contrast/image quality
as possible (without a priori knowledge about intensity distributions or
object shape etc.)

thanks for your help,

Klaas


P.S.: I correct each image with bias and dark images before adding them
to the sum
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