From your comment on the E-1 dynamic range test:
"Now, for the opposite end of the spectrum. The Olympus E-1 sacrifices
the highlights for preservation of the shadows. This is different than
the Canon cameras which sacrifice the shadows for preservation of the
highlights. Where "Expose-to-the-Right" is a recommended procedure for
the Canons, exposing for the midtones or even the shadows is recommended
for the E-1."
Me thinks you don't really understand "expose to the right". It has
nothing to do with sacrificing the shadows for the highlights or
vice-versa. It's intended to avoid sacrificing anything. It's based
strictly on the characteristics of the binary representation of the
brightness of a pixel. Increasing the brightness level of any pixel
(regardless of the camera that produced it) has a tendency to create
posterization due to the multiplication and then integer rounding of
small binary numbers. Decreasing the brightness has no such effect.
Therefore if the exposure is not perfect it is better that it be
overexposed and reduced in brightnes in post processing as long as the
highlights are not blown.
For example: I have 3 pixels with brightness 10, 11, 12. I increase
their brightness by one stop by multiplying by the square root of 2 =
1.4142 which yields (after rounding) 14, 16, 17. But reducing the
brightness of overexposed pixels 245, 246, 247 by dividing by the square
root of 2 yields (after rounding) 173, 174, 174. After dividing down I
end up losing some tonal information by creating two pixels of the same
value but I have not created any tonality "holes" as in the jump from 14
to 16 above.
Chris posted a photo the other day that showed exactly this problem.
The histogram of his image showed a lot of spikes and holes caused by
brightness manipulation. This is also why you want to do any image
editing in 16 bits even if the original image is an 8 bit JPEG.
Chuck Norcutt
On 9/17/2010 6:19 PM, Ken Norton wrote:
>> Yeah! Let´s do it and show the charts to everyone. It took me too many hours
>> to generate them. Norman Koren (The Imatest programmer) told me he was
>> amazed with KODAK KAF-5101 sensor!
>> Shadow information is awesome. Yeah!!! Highlight EV is very narrow. I think
>> is the reason why E-1 underexposes.
>> I am pretty sure many people thinks E-3 had wider dynamic range compared to
>> E-1. :)
>
> LOL, not in my tests! The E-1 gives what appears to be at least one,
> if not two stops more recoverable shadow detail than the E-3. I
> regularily underexpose by a full stop and have to pull it up in
> conversion. Not a problem at all. There are few cameras you can do
> that with and still keep your sanity. Noise? Well, no E-1 image is
> clean at any brightness level anyway, so it's not much of an issue.
>
> I think I adequately proved this point with this test:
>
> http://zone-10.com/cmsm/index.php?option=com_content&task=view&id=493&Itemid=1
>
> AG
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