Earlier this week, as I waited outside to flag down a delivery truck, I happened to notice that the view down the street was rather pretty. It was about 10 AM, but the sun was behind a cloud, so the light was pleasantly soft.
I popped inside, spent a couple minutes looking for my camera, and when I got back out.. of course the sun had moved past the clouds, ruining my soft lighting. Rather than admit defeat, I took several shots one stop apart for HDR processing.
This was the final result. Rather than using the typical local contrast enhancing tonemapping that sometimes produces strong halos, cartoonish colors, or exaggerated contrast, I processed the color and luminance separately, using Photoshop to roll off the highlights in order to give the image a more natural quality. There's roughly two to three more stops here than my camera is capable of capturing with one shot, and very little noise in the shadows: perhaps doable with one RAW shot with a good DSLR, but this was shot with a Canon Powershot A700.
What do you think? Does it look good, or strange? (I like it, but I'm obviously biased.) Anyone curious about my process?
bsc2112, here's one of the source images (rescaled - if I don't do it, flickr will). I think it's the one most similar to the final result in terms of overall tone.
1. Create or open your 32-bit HDR image in Photoshop.
2. From your HDR master, create two 16-bit RGB images. (You'll want to Duplicate the HDR for this.)
2a. One image is converted to 16-bit using Photoshop's "Exposure and Gamma" option, with the Exposure slider pushed far left and the Gamma slider pushed far right. This should give you an image with lots of color but little or no contrast.
2b. The other is first desaturated by any means you prefer and then converted to 16-bit using Exposure and Gamma again. This time, adjust the sliders so that the darkest part of the image that you want to retain detail is just barely black, and the lightest part of the image that you want to retain detail is just barely white. If you can't tell whether you're clipping or not, err on the side of retaining more dynamic range; it's easy to fix in the next step. This should give you a fairly dull-looking B&W image.
3. In your B&W image, open a Curves adjustment layer. What you want to do here is set a point somewhere near the white end of the curve and drag it up to make that point lighter (think something like input 190, output 220). What this will do is increase the contrast in your shadows and midtones and decrease it in your highlight areas. In other words, where your source images might have had highlights that clipped and blew out, now you'll have a more film-like response. Depending on your image you might need to make other changes in the curve as well. This is the trickiest part of the process, especially if you lack experience working with curves and don't know what adjustments to make, because there's no magic number or formula that works every time. When you're done with this step you should be happy with your overall tone and exposure, and your image will look a bit dull due to a lack of local contrast.
4. Make a copy of your image with its adjustments in a new layer. You can do this using Stamp Visible, or by converting the background later and its adjustments into a Smart Object that you duplicate and rasterize.
5. In the new layer, apply Unsharp Mask to restore some local contrast. The trick here is to find the right radius (I have an action that performs several Unsharp Masks at different radii, then blends them, which is a bit inelegant but often eliminates this kind of guesswork) and to not apply so much that you create obvious halos or clipping.
5a. You can also do fine sharpening here, or on a duplicate layer if you prefer.
6. Switch to the other image, the one with the color, and copy-paste the whole thing into your luminance image. Set the blend mode to Color.
