A few months ago I got an upgrade to my Photomatix software. When I opened the updated version of Photomatix I noticed an option for "Exposure Fusion". After blending exposures with it a few times I realized it did a much better job of keeping the image looking natural, real, and believable. I have been considering doing a blog post describing this method but haven't done it up to this point because I knew it would be quite time consuming to do a thorough one. I came across another blog post today which did a good job of describing the technique much as I would have. I have never met Kevin McNeal but he has some of the best wilderness photography that you will ever see. If you go to his blog you can get a rundown of this method of combining images. http://kevinmcneal.wordpress.com/2010/02/07/exposure-fusion-best-way-to-blend-images/
Some of what I do is a little different than Kevin's method. Like most post-processing techniques there are several ways to get the end result you are looking for. In the next paragraph I will detail the differences in how I do it. I suggest going to his blog and reading it before proceeding here.
Guanajuato Opera House
The U Drop InnWhen you choose your source images in Exposure Fusion, you will notice that it says "Note: Blending exposures works with converted files. For good results with Exposure Blending, it is recommended to convert your Raw files into Tiff or Jpeg files." I have taken their word for it and done it that way. I open the raw file that is in the middle of the range of exposures that I have taken. I will make many of the same adjustments in the raw converter that I would if it was a single exposure I was going to use for my image. However, I won't worry too much about the clipped shadows or highlights. The other exposures should take care of those values. I will save it as a TIFF. I then open the other raw files in my range of exposures and make the same adjustments to them before saving. The brightest and darkest exposures may get a small tweak from the adjustment brush if an area needs it. I then choose these images to be Exposure Blended. I will start with the default values in the final dialog box before processing the images. It is easy to get an understanding of what the sliders are doing. A description of what they do comes up when you mouse over them. I have found I can improve the image more by adjusting the sliders. Unlike tone-mapping they don't do strange unreal things to your image if you get a little heavy handed with them. When happy with the way it looks I will tell it to process the image. I then give it a name and save it. I will open it back up in Photoshop. I will then look at the brightest areas of the darkest exposure and see if I think some of the detail is missing from the processed version. I will also look at the darkest area of the brightest exposure and see if it will improve the processed version. If I believe the processed version still didn't retain all the detail in one of these areas then with the move tool I will drag the TIFF image which includes that detail onto the processed version. Dragging while holding down the shift key should line it up perfectly when you let go. I then click the icon for a layer mask while holding down the alt key. This creates a black layer mask which hides the new layer. Then I choose the brush tool set to white with a 10-20% opacity and gradually paint back in the parts of the layer I want to keep. I paint and change the brush size and opacity until happy with the results. I repeat this with another layer if necessary. I will probably make some other small adjustments in Photoshop but the image is usually looking pretty good at this point. I will look at the image and try to decide if it needs something else done to it. If not, its finished.