Subject: Re: 50% Gray
I'm not sure what you mean by a 50% fill. Some people use a stepchart (such as the Kodak Q14) as an aid. The A in the chart corresponds to highlights and the B to shadow. The M appears as mid gray in a gamma 2.2 image, but the actual reflectance of M is ~20, not 50%
In digital exposure, most experts like to place the highlights as far as possible to the right (exposure to the right, ETTR) so as to maximize information and minimize noise. This is best done in the field by taking a reading from the highlight and exposing accordingly (there may not be a definite gray point). The digital sensor is linear, so this poses no problem and the tones are not distorted.
Then in ACR you can then place the gray, black, and white points where they should be. For a dark low-key subject with ETTR, the resultant image will have to be darkened if you want to reproduce the original appearance of the scene as best as possible in the print.
In summary, a gray card may not be that useful under these conditions. I'm not sure this answered your question, but it may help
View All Messages in adobe.photoshop.camera.raw
50% Gray =>
Copyright © 2006 WatermarkFactory.com. All Rights Reserved.