[Zac Pujic]

David

To do LRGB, you need Photoshop. You don't need the newest version, but at least version 5 since you need the layers function. The luminance channel (L) is just a b/w image with high detail obtained from a good b/w camera. The colour (RGB) channel is a colour image which can be poor and noisy and is made using a poor colour camera. Here is how I do it. Others may have different techniques.

To combine the two, you open the colour image and paste the b/w image into it. This gives you two layers. You then make the top layer 50% transparent so you can see the bottom layer. You then rotate and rescale one of the images so they overlap, as closely as possible. Obviously you have to have two layers so that you can control one image independently of the other.

Finally, you go the layers properties for the b/w image and make it "luminance". This is usually the last (bottom) option in the newer versions of photoshop.

This now gives the resulting image the image quality of the b/w image with the colour of the colour image. I usually pass the colour image through the photoshop noise filter. Then tweak the image so dynamic range in the histogram covers the whole range.

I usually use photoshop but I think other programs, perhaps paint shop pro, can be used instead. I'm not sure.

I hope that helps.

Zac