how to compensate for low dynamic range monitors?

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kiki - 29 Nov 2004 08:18 GMT

Hi all,

I have a bright image which is taken using good camera, and I upsampled it
to a higher resolution(say NxN larger size)... and then applied some image
processing, color space conversion, gamma transformation, inverse gamma,
filtering, etc... and the new image look dark...(or equavalent, the LCD
monitor does not support the new image due to its limited dynamic range...
what can I do to compensate for the low dynamic range and still make the new
one viewed from several meters a way the same as the old one?

Thanks a lot,

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Jerry Avins - 29 Nov 2004 22:23 GMT

> Hi all,
>
[quoted text clipped - 7 lines]
>
> Thanks a lot,

I can guess what you're doing because of what you've written in other
threads. I don't like to guess, mostly because I'm too likely to waste
time and cogitation by guessing wrong. If this is the same problem you
already provided details about in another thread, starting a new thread
won't get you new information or recruit new gurus to your cause.

Examine the image after each processing step to learn which one dims it.
Learn how to do gamma correction. (Google) Brightness is increased by
adding a constant to each pixel. Be sure to make it color neutral.
Contrast is done by multiplying, but adjusting offset (brightness) is
often also needed.

You seem to be doing sophisticated transformations on images without
having enough of the ground concepts to guide you. Dig into that. Think
about the brightness and contrast controls on an old B&W TV.

Jerry

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