I am noticing some anomalies in some of my recent HDR attempts when shooting a nearby stream. I am enclosing a full size crop of the issue.
These black spots are cropping up after merging three bracketed exposures in Photomatix pro for tonemapping.
Any thoughts on what they are and why this happens and what the fix might be? I was getting a lot of purple fringing around the highlights in the water, but that was fixed through lens color corrections in LR4. This is something else. It is not showing up in each individual shot and it only seems to have occured in shots containing water.
That looks to me like an issue of the water reflecting and not merging evenly in three exposures... Try taking your median shot raw file, kick it down -2 and save, then +2, and save. Then take those three images and merge and see if you get the same result.
I would try it again with the remove ghosting off. Trying to remove ghosting of moving water is likely introducing errors.
I tried this and the merged file came out exponentially worse. There were black spots everywhere.
Originally posted by Sirashley:
That looks to me like an issue of the water reflecting and not merging evenly in three exposures... Try taking your median shot raw file, kick it down -2 and save, then +2, and save. Then take those three images and merge and see if you get the same result.
I am thinking this is what happened. The highlights changed with each shot so Photomatix was trying to merge an overexposed highlight spot with an underexposed non highlight spot. After saving and merging the median shot with 2+/- exposed images, there were no dark spots to be found.
ETA. I forgot to say thank you to all for your input!
