Sometimes it advantageous to replace a channel in Photoshop. Below is an HDR photo in Photomatix, saved and ready to load into Photoshop. Three exposures were used to make the HDR photo. Notice the orange center. Hard not to, isn't it?!

That's the result of a channel being clumped up. This was a shot with a Canon D60. Highly saturated yellows and reds could be an problem with Canon D60 images. I have many images from bright, sunny days with highly saturated flowers where the reds or the yellows took on ugly artifacts like these with my old D60.

Saturation boost is characteristic of HDR photography. In this case, it took a bad problem and made it worse.

One way of attacking the problem is to make a selection of the orange center and work on that. With effort, you could get a good selection and you could finesse the color to blend more smoothly.

An easier solution became obvious when I examned the individual channels. Here's the Red channel followed by the Green channel:

No halo in the red channel. Nice smooth petals. But, there's the halo in the Green channel. Not so pronounced when you look at it in a single channel, but that's the culprit.

My obvious thought was to replace the Green channel with the Red channel.

Wait a moment! There's a one important difference! The Green channel has lots of important detail for the green leaves. The Red channel doesn't. The flower would end up looking like it was suspended in space, if I did replace the entire Green channel.

The solution was to use a selection and replace only the flower from the Red channel. I used the Magic Wand tool on the Red channel with a Tolerance of 20. To get the black "eye" in the center, I used Quick Mask and the Brush tool. Total time, just a couple of minutes.

The result after replacing the Green channel was much smoother color transitions on the petals. The ugly orange halo was gone. By using a selection to limit the channel replacement to the flower, the green leaves remain untouched for a nice color contrast.

The Red channel allowed too much Green to emerge, however. The color of the flower shifted from the red side of yellow to the green.

That was an easy two step fix. I started by applying Levels to the new Green channel. I used the Gamma slider to darken the flower petals. 

A Color Balance adjustment layer refined the color further. I left the selection in place. That way the Color Balance adjustment would only affect the flower, not the background. Here's the Color Balance settings and the result:

From here, some clean-up of the flower would be necessary. Anyone who has done any macro photography or near-macro photography of flowers is familiar with the tiny petal imperfections, dust, and dirt that plagues outdoor photography. It can take quite a bit of time with the Healing Brush to clean up a flower.

I decided to try a stylized effect. I used Nik color Efex Pro 3, in particular, the Foilage filter. That boosted the saturation further. 

Goosing the saturation had the benefit that many of the tiny imperfections in the petals were concealed. The result is a stylized effect that's common with HDR photos. Some like the effect. Some might feel the effect here is a bit "over the top." All of that is easily adjusted.

A damaged photograph was quickly and easily recovered by replacing a channel.

You can download a .PDF version of this tip by clicking here . . .

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