cgardner Offline Upload & Sell: Off
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Working for years in reproduction I'm very aware of how image tonal values change during the workflow. For example when I did QA for the production of maps at National Geographic in the mid-1970sto get the desired 30%, 40%, 50% and 60% halftone values in the ocean we needed to start with 27%, 36%, 45%, and 56% screen tints. This was determined by starting with 5% - 95% target and plotting how the values changed at every step of the multi-stage workflow.
My approach to digital exposure is the same. As SOP intentionally underexpose my RAW files about 1/3 stop under clipping because I've found that if I don't by the time I make a small 8-bit JPG in sRGB the file would have blown highlights, particularly in the red channel of the skin. When using flash and able to control the tonal range at will with fill, I intentionally over fill the RAW so the shadows are lighter than I want the them in the final images which keeps all the shadow detail further away from the point where noise starts to exceed signal and is seen.
The the process of doing flash testing for tonal range and expose I noticed that by simply exposing per the clipping warning so no solid whites where clipping I rarely got any clipping at the end of my workflow in the 8-bit JPG in sRGB. That makes sense because the clipping warning in camera is based on a JPG the the RAW. In the shadows I judge the exposure based on seeing detail in the playback, and when using flash knowing what ratio of key and fill will fit a full .05 - 2.3 reflected density range to my sensor. In the studio and elsewhere when convenient I use white and black towels as 3D targets and proxies for the full range.
My workflow winds up being the reverse of working with B&W negative where you'd err in exposing for shadow detail and often need to "burn-in" the highlights a bit if over development of the negative caused the highlights on the print to "clip" and wash out. With digital err on the side of underexposing the highlights and overfill the shadows to avoid clipping in the final JPG (not the RAW).
In my PP workflow I create a "Master Edit" copy of the file in CS5 and in it keep the highlights and shadows about 1/3 stop under and over exposed relative to the final eye dropper readings I want. I make the final "trim cuts" after resizing and converting it JPG and sRGB.
I check the JPG in Levels holding down the alt/opt key and clicking on highlight and shadow sliders to see what if anything is clipping. Usually the 1/3 stop allowance in the 16-bit ProPhoto RAW is enough that no tweeks are needed, by I will move the end point sliders in Levels to adjust tonal range as needed for screen files and move the middle slider back and forth off 1.0 to see how that affects the appearance.
Adjustments for prints are based on on screen appearance but how the shadows and highlights turn out on the prints, which varies depending on whether I print on my ink jet or at Costco. The same is true for mid-tone contrast. I find that a file that looks perfect on screen will tend to print darker. The amount that is noticed varies with the content of the photo. I compensate for the gain by moving the middle slider in levels left to lighten the midtones. If printing a file in several sizes I make copies scaled to size at printer native (printhead spacing) resolution applying USM and other tweeks as need for that size.
The poll is because I'm curious how many others take these workflow changes into account. I often see clipped red channels in people shots I C&C and scenics that lack a full range of detail in the JPGs posted.
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