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Arthur Morris
01-27-2009, 07:23 PM
This image was originally posted in Avian. Juan kindly educated me as to handling over-saturated REDs. Be sure also to check out Juan's original tutorial here:

http://www.birdphotographers.net/forums/showthread.php?t=29869

What I learned has helped me to consistently get the right exposure when creating sunrise/sunset silhouettes using Robert O'Toole's Kelvin White Balance trick. See Bulletin 285 in the BAA Bulletin Archives. It will be posted in a day or two.

This Roseate Spoonbill was photographed at Merritt Island NWR with the handheld Canon 400mm f/4IS DO lens and the EOS 1D MIII at the same pool where I photographed the flock of Snowy Egrets (Dive Bombers) that I posted yesterday. ISO 400: 1/1600 at f/7.1 (should have been f/8 but I recovered the blown hightlights while converting in BreezeBrowser. AI Servo AF with the central sensor only. Slight crop.

If you are not out at Alafia Banks with James Shadle it is not often that you have spoonbills landing right in front of you; sure was fun.

All comments welcome. Don't be shy; I am here to learn too!

Juan Aragonés
01-28-2009, 10:49 AM
Artie I would crop just a litle bit on the top and right of the frame but keeping the feeling of empty space around the bird. The pose of the bird with "flaps" raised reminds to me an aircraft ready to take land. You know that I am a big fan of toning down BG in images like this one.... ;-)

By the way, some whites in the red channel are on the 255 level

Arthur Morris
01-28-2009, 10:57 AM
Artie I would crop just a litle bit on the top and right of the frame but keeping the feeling of empty space around the bird. The pose of the bird with "flaps" raised reminds to me an aircraft ready to take land. You know that I am a big fan of toning down BG in images like this one.... ;-) By the way, some whites in the red channel are on the 255 level

Thanks on all counts Juan. I cropped as suggested for the repost but have several questions.

#1: I am unsure of what you mean when you wrote, "You know that I am a big fan of toning down BG in images like this one.... " Are you saying that you like that in this image or that this image needs the BKGR toned down. I think the former but wanted to clarify.

#2: Please explain how I check the whites in the red channel. The optimized TIFF showed no overexposed highlights but I must be missing something...

thanks again on all counts.

david cramer
01-28-2009, 01:57 PM
This slight shift to the right of the red channel is often a result of converting a highly saturated adobe rgb or prophoto rgb color space to srgb for web jpg. It results in a loss (slight in this case) of saturation of and tonal differences in the reds. Here it shows up along the front edge of the wings. The tiff and print should be fine.

I like the cropped version best. Overall a beautiful angle on the bird.

Juan Aragonés
01-28-2009, 03:58 PM
[quote=Arthur Morris;204481]

#1: I am unsure of what you mean when you wrote, "You know that I am a big fan of toning down BG in images like this one.... " Are you saying that you like that in this image or that this image needs the BKGR toned down. I think the former but wanted to clarify.
quote]

#1 What I mean is that, instead of the fact that the sky is OK in terms of exposure, I think that a slightly darker sky would improve the result and the reason is very simple: images with a high contrast and/or a high saturation are very attractive for the human brain (and for the avian brain too due to common biological reasons related to vision). If you want to increase the contrast of an image, and made it more attractive for the viewer, you just need to enhace the differences between dark and bright areas in the image. The spoonie is very bright and if you tone down the sky then the contrast would increase. Of course, toning down the Bg is an alteration of the original Bg but during many years photographers have been using fifferent sistems to do excatly the same (using filters, working on the development of the negatives, etc).
In the attached file it is possible to see the effect of toning down a part of the image. The spoonie is untouched but the contrast it is clearly different in the four versions (I prefer the second version from the top)

Juan Aragonés
01-28-2009, 04:36 PM
#2: Please explain how I check the whites in the red channel. The optimized TIFF showed no overexposed highlights but I must be missing something...



There is an area that is very bright in the spoonbill but very few pixels are on the 255 level and they are located on the red channel. You can check that by several ways. In example, select the eyedroper tool ang the info panel and if you place the eyedroper on different areas of the image you will see the levels of each pixel on each channel. Or you can go to the levels adjustment panel and select the histogram for each one of the three channels. As you can see, the histogram of the red channel show some pixels in the 255 level.

Being honest, I think that the number of hot pixels in the red channel is almost unnoticeable and doesn´t affect the overal image quality. Anyhow, this is a good oportunity to explain how I test if I have this problem in my images and to learn how other members do the same. :)

Juan Aragonés
01-28-2009, 04:38 PM
#2: Please explain how I check the whites in the red channel. The optimized TIFF showed no overexposed highlights but I must be missing something...

Here is the second attachment

Arthur Morris
01-28-2009, 07:22 PM
Thanks a ton Juan on all counts. It is rare that the sky looks the way I remember it but I do not concentrate enough on the sky. I will from now on. Here is a version that employs all of your tips. BTW, the Red Channel in the converted RAW was fine till I worked on it. The Red Channel lessons are esp. important as I have been doing lots of work at sunrise (often at 7000K) and have been pushing my EXPs to the right, so knowing how to check on hot pixels in the Red Channel is a plus. The sky in my repost is probably darker than in your #2 but I like it.

Juan Aragonés
01-29-2009, 03:52 AM
Artie, I am glad to hear that you have found usefull the information and I like your repost, the sky is more dramatic :-)


David Cramer wrote: "This slight shift to the right of the red channel is often a result of converting a highly saturated adobe rgb or prophoto rgb color space to srgb for web jpg. It results in a loss (slight in this case) of saturation of and tonal differences in the reds. Here it shows up along the front edge of the wings. The tiff and print should be fine."

I think that you are right David. Sometimes our master file is OK but when we convert to a different color space, type of file or web size the image show some deagradation.

Juan Aragonés
01-31-2009, 02:31 AM
... The Red Channel lessons are esp. important as I have been doing lots of work at sunrise (often at 7000K) and have been pushing my EXPs to the right, so knowing how to check on hot pixels in the Red Channel is a plus.

Artie, I think that you could find interesting the information about problems with the red channel/saturation/details in a couple of posts that I wrote in the following thread (http://www.birdphotographers.net/forums/showthread.php?t=26485):)

Arthur Morris
02-08-2009, 12:19 PM
Thanks again Juan. I would advise that everyone visit the link in the pane above. It is excellent and informative.

Robert Amoruso
02-10-2009, 06:32 AM
Artie,

The link in your first post at the top is broken.