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Repairing blown highlights and/or red channel (was: Another newbie concert picture)
Tom Mann
Guru
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The main reason the image looks the way it does is because the red channel is wildly overexposed (aka, "blown"). This happened for two reasons: (1) The dark background fooled the auto-exposure system in the camera into trying to lighten up the image; (2) the gelled stage lights lighting the subject have a spectrum that is composed of almost all red, no other colors. This is a *very* commonly occurring problem with concert and theater photos.
In the future, the way to prevent this from happening again is to look at the histogram on your camera and manually reduce the exposure until you don't see a tall narrow spike on the extreme right end of the red channel histogram. Doing so will make the rest of the image look quite underexposed, but it's much easier and more visually pleasing to increase the brightness of these parts after the fact in PS than it is to try to fix a blown channel. If you don't have, and/or can't borrow a camera that will let you do this, do whatever is possible with your camera to decrease the exposure by 2 or 3 stops. This amount is just a guess, but it's better than nothing.
With respect to repairing this image, to be honest, there is almost nothing that can be done to make it look even half-way good. About the best one can do is to look at the R, G, and B channels separately, see which one has the most detail in the important areas (eg, the face), and use that channel to control the luminosity of the entire image. Since this sort of image blooming tends to put bright halos around objects, you probably will also have to manually deal with the edges in PS. Here's about the best I could do in 10 or 15 minutes. I used the green channel for the luminosity information.
In addition to the blown channel problem, this image also has lots of noise. There are two types, the normal digital noise (looks kinda like film grain), and bright spots of light. You'll also have to deal with both of these using conventional NR techniques after you have done the best that you can to fix the blown channel issue.
HTH,
Tom M
In the future, the way to prevent this from happening again is to look at the histogram on your camera and manually reduce the exposure until you don't see a tall narrow spike on the extreme right end of the red channel histogram. Doing so will make the rest of the image look quite underexposed, but it's much easier and more visually pleasing to increase the brightness of these parts after the fact in PS than it is to try to fix a blown channel. If you don't have, and/or can't borrow a camera that will let you do this, do whatever is possible with your camera to decrease the exposure by 2 or 3 stops. This amount is just a guess, but it's better than nothing.
With respect to repairing this image, to be honest, there is almost nothing that can be done to make it look even half-way good. About the best one can do is to look at the R, G, and B channels separately, see which one has the most detail in the important areas (eg, the face), and use that channel to control the luminosity of the entire image. Since this sort of image blooming tends to put bright halos around objects, you probably will also have to manually deal with the edges in PS. Here's about the best I could do in 10 or 15 minutes. I used the green channel for the luminosity information.
In addition to the blown channel problem, this image also has lots of noise. There are two types, the normal digital noise (looks kinda like film grain), and bright spots of light. You'll also have to deal with both of these using conventional NR techniques after you have done the best that you can to fix the blown channel issue.
HTH,
Tom M
Image is so red to start with, i tried to post earlier but the site was acting up again?