![]() ![]() ![]() Every photo manipulation program has an option for lightening/darkening an image. In Graphic Converter I simply used the Brightness with Curve dialog. I can see the tree branches, and texture in the grass, and to some extent texture in the leaves. I don't feel the tone is overly blue now, plus all kinds of details pop out. However as we see, darkening the picture a bit really improves it. The image looks much better but it still looks too dark. In that sub-menu is a choice to bring up the Color Mixer dialog box. Namely - in Gimp, on the Colors menu, there is a Components sub-menu. In other programs, like Gimp, you are instead put into a dialog box and there's a little mumbledy-foo to manage the swap. In Graphic Converter, in the Effect menu there is a sub-menu named Channels and one of the choices is Swap Red and Blue. If nothing else it looks too blue, maybe. To swap red and blue means, for each pixel, to take the Red value and put it in the Blue slot, then take what had been the Blue value and put it in the Red slot.Īs you can see the image improved tremendously. The first time I heard that I went "swap the what?" I think what's meant is - each pixel in an image is made of a Red, Green, and Blue value. The next common recommendation is to "swap the red and blue channels". However there are two changes that need to be made. Therefore - for this picture, when asked to set the white balance point I clicked on the grass. ![]() In the infrared - since grass or tree leaves show up as white - the recommendation is to set white balance using grass or trees as the reference point. In the camera you're asked to point the camera at something that should be taken as "white" and the camera sets its white balance appropriately. ![]() This is very similar to setting a custom white balance in most digital cameras. It asks you to click on a place in the picture that should be taken as white, and it recomputes the image appropriately. Gimp's white balance tool doesn't support this, unfortunately, since it only has an "automatic white balance" tool.įor Graphic Converter the "Effect" menu has a choice named "White Correction". In Graphic Converter (and some other programs) you can set a custom white balance using a color picker to select a section of the picture that should be white. We'll take this a bit further, but we first need to talk about what I did. We could almost stop here (after darkening it a bit) because it looks like an old-school black-and-white infrared photo. Immediately the picture is so much better. You're about to make a change to the photo and with the duplicated layer you can easily flip back and forth to see how well the change worked out. The first step - if your photo editing program supports layers (as Graphic Converter and Gimp do) - duplicate the layer. How do you take a good infrared picture with a camera that doesn't support a custom white balance? Fortunately most photo editing programs (Gimp et al) can manipulate the white balance. But, even if I could go back in time, the camera in question doesn't even support setting a custom white balance. In this case I took the picture 15 years ago, and lacking a TARDIS I can't go back in time to set the white balance in the camera. For example the recommendation is to point the camera at some grass to set the white balance - because in the infrared grass looks white. Obviously in the infrared the camera doesn't have a clue what white looks like. It's widely recommended to use a camera that can set the white balance. ![]()
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