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 Inn
When 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.
Thanks for the run down of your technque Clark. This new method is well worth exploring to give your image a more natural look and going down the road of HDR which is unrealistic. Cheers
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