I talked about how to do windows in an earlier post, and want to let you know that is not the only way to do it. Another, equally effective, and perhaps easier way is as follows:
When shooting the interior of a home or business, and when there is a window in the scene, shoot at least two exposures of the exact same shot. Take one shot that is properly exposed for the interior, and one that is exposed for the outside light pouring in through the window.
The exposure for the outside is probably at least one stop over the exposure for the inside, so you’ll have to underexpose your interior to get the proper outside exposure. You can also use the bracketing feature if you have it, and shoot one normal exposure and one one stop under, and one two stops under the normal exposure.
You can adjust the images in photoshop later, but the less image manipulation you do after the fact, the better the image quality, since you don’t have to re-arrange as many pixels. Plus, it never hurts to have too many options for window fixes.
Once you have transferred the images to your computer, go into your image editing software, and open the “normal”
exposure image of the window. Using the polygonal selection tool, outline the entire overexposed window, and then ctrl-x it. This should leave a black hole. If not, you will need to make the selection black, otherwise the other window image will not show through.
Open the second image of the same window and drag it onto the first image (this will create a new layer). Change the transparency to a setting (usually 50% works) that allows you to see the first image through the second, and overlay the second image on the first, so that everything lines up. Change the transparency back to 100%, and select the first image as the top layer, by moving it up in the layers tab. Save the image.
What you should now have is the interior and the window properly exposed. Since digital “film” cannot handle the range of lighting that film can, you have to make some adjustments manually, or use specialized filters or supplemental lighting to get the light right. But if you can combine two images of the same scene, with both a window and what is seen through the window in proper exposure, you will have a much better picture.
You may also have to do the same thing with really bright light shining in on the floor or other areas of the scene. Usually, it will be okay just to do some dodging and burning to handle small areas like that.