Issues with HDR

[cmk]

Hi-

I am getting some strange results when attempting to use the Photoshop (CS4 Extended) HDR function. The resulting image (while still in 32 bit with no changes made to the image at all) shows some random colors in certain areas. The 'input' images do not show any of these random areas of color.

Obviously this is occurring in the Photoshop stage, but cannot figure out why (I would imagine that this may be a semi-common problem for individuals new to HDR)

Any ideas? Thanks!

[cmk]

Here is the image result I am getting (with the random spots of colors). Please note that nothing at all has been done to these images since they were moved off of my camera onto the computer, so I am aware that I will want to process them quite a bit. My question purely relates to the random incidents of color I am getting upon merging them into an HDR file. I am using Photoshop CS4.

Please note in the center of this image the random blue that appears on the water. This also appears in other areas of the image that are harder to see at this image size.



Note in these 'source' images that none of this blue appears in that area.

[David]

Hi cmk - I'm not familiar with Photoshop CS4 nor with its HDR facility. So I can't say whether the oddities you notice are caused by it. However, a way forward would be to download free HDR software such as Picturenaut (Google and ye shall find) and see if the same effect appears there. My suspicion is that the problem relates to the tone-mapping part of the procedure (see excellent posts by Colin Southern on tone-mapping).

Cheers

David