PDA

View Full Version : Whooping Crane Pair



Michael Lloyd
03-06-2012, 10:08 PM
I shot this on Sunday, down near Rockport, TX. The Texas count this year was up to 270 but i've seen the number described as murky due to the birds ranging as far north as Austin. Due to the drought the marshes are too saline and the blue crab population is way down. Blue crab is a staple of the Whooping Crane diet.

On to the question. Most people will see the blown highlights on the posted image. At least they will if they can ignore the leg growing out of the front cranes neck (female I believe). :t3 Here's my question. When looking at the raw file in ACR the highest white reading that I get is 240. That's right out of the camera. No manipulation. Yet there is a spot on the JPG, and TIF file for that matter, that is very definitely blown. Info shows 255 and it's apparent to the eye. Why is that? I went back through the various layers and all that I did was a mask and background noise removal followed by a mask and smart sharpen.

Kerry Perkins
03-08-2012, 10:02 PM
Hi Michael, somewhere in the processing the red channel got clobbered. You say it is in the TIFF file after you convert from RAW? In that case I would have to say the ACR is doing it. I guess the obvious thing to do would be to go back to square one and check the whites at every step. I have seen both noise reduction and smart sharped push some whites over the line. The image as posted has a magenta cast, so lowering the red channel (and a bit of blue) in ACR would be a good idea anyway, and it might save the whites from clipping. The only color channel that shows 255 in the image is red. If you use one of the tools I talk about in the sticky at the top of the forum page you can check the color values easily every step of the way.

Michael Lloyd
03-08-2012, 10:20 PM
Thanks Kerry. That gives me a place to start. I'll check the sticky as well. I didn't notice the magenta cast so I'll check that too. Sometimes the white balance dropper in ACR gets a little happy with the magenta slider.

Kerry Perkins
03-08-2012, 11:16 PM
Michael, I agree regarding the eyedropper tool. Like so many other "automatic" processes, it often falls short of what the human eye can do.