The Joy of Pixel Density

Started Jul 13, 2008 | Discussions thread
alanr0 Senior Member • Posts: 2,164
Re: The Joy of Pixel Density

John Sheehy wrote:

8 hours, and only one reply. The silence is deafening.

Well some of us are about to go to bed, and can't understand what's so difficult to understand in any case.

On the other hand ...

Graystar wrote:

I just want two images...from the same sensor area...resize the
higher resolution to match the lower resolution...

Which John has put in the two small inserts

of a scene with a
wide dynamic range. That's it. Oh...maybe some clear labeling. And
no pushing. Is that too much to ask?

With no pushing JPEG images won't show a wide dynamic range. That's the way JPEGs are. The images John has posted would be mostly black.

If John uses something close to the SRGB tone curve, anything not blown out in the posted image will have less than 8% pixel values (21/255) - somewhere between X and Y in the gray scale at the bottom of Phil's review pages. With the same 7 stop push, gamma=0.45 would put the brightest parts of the crop around 11% (X on the gray scale).

http://en.wikipedia.org/wiki/SRGB
http://www.w3.org/Graphics/Color/sRGB.html
With a linear tone curve, the image would be indistinguishable from black.

Are you still confused about the difference between dynamic range and tone curve?

Cheers.
--
Alan Robinson

Post (hide subjects) Posted by
ck3
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