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Good job Michael. That's closer to my expectations too. Todd > > Mark, > > Thanks for posting. That's the first time I've witnessed anybody posting > anything for examination when this topic comes up. I appreciate it. > > Now, in examining the images and their histograms, what I see is a lack of > contrast in the 8 bit edited image relative to the 16 bit edited in the lower > end. If the exact same curve adjustment operations were performed, I don't > understand how this difference came about. Anyway, when I adjust the 8 bit > image's curve lower end to closely match the 16 bit image curve's lower end, > then the results are almost identicle. > > I've posted the 8 and 16 bit edited images that you posted untouced. I've also > posted the adjusted (or corrected as I call it) 8 bit image. Alos, I've posted > the 8 and 16 bit histograms along with the 8 bit corrected histogram. If you > notice, the orginal 8 bit image has a relatively narrow range in the low end. > Narrow ranges will ALWAYS lead to dull/flat looking images. The 16 bit and 8 > bit corrected ranges are pretty much the same and thus, the results are pretty > much the same. > > Navigate to http://greeraa.com/albums/bit_depth/ to see. > > --- email@example.com wrote: >> Mike, >> >> Here is a real world comparison for you. >> >> http://www.pbase.com/mark_kn/16bit_vs_8bit_editing >> >> The image was taken with a Canon D60 in RAW mode and converted to a 16 bit >> TIF. >> A duplicate was made and converted to 8 bit. >> An equal amount of levels were applied to both images. >> The files were then resized to 640x480 for speed of loading and saved as JPG >> quality 10. >> No other manipulation was performed. >> >> Download the images (they are ~80k each). Look at the original. Notice how >> far >> down in the shadows the lower portion of the image is. Now observe the >> Johnson >> grass in the lower right foreground on the 16 bit edited file compared with >> the >> 8 bit edited file. Draw you own conclusions. >> >> Regards, >> >> Mark K. - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.