Three yeas ago, Don Smith and I took a trip up the California and Oregon Coast across the Columbia River Gorge and back through North Central California. We had a great trip, saw and photographed some amazing sites.
Recently I was looking through my portfolio and came across this image from that trip. I wanted to smooth out the moving water with a long exposure so used a Hitec 10 stop Filter. When I looked at the results 3 years ago, there was a terrible red cast to the whole series of images and I didn't know what I did wrong or how to process the photo.
When I looked back at it a couple days ago, the issues were a little more obvious. First problem, the Hitec 10 stop filter! Most 10 stop filters create some color cast and this one is no exception adding a red tint to the image. The second issue surfaced when I tried to remove the red color cast I came out with an image that was much too blue and green. Identifying problem number 2 required the realization that I had set my camera white balance to auto when I took this series of photos. The camera did not really understand what to do with this image and the color temperature it set for the image was way too warm.
Color temperature is not an issue if you shoot in RAW which I do. Had I shot this in JPEG, it would have probably been unrecoverable. The solution: 1) dialing back the color temperature to a more natural daylight temperature of 5000 degrees which got rid of the color temperature problem and 2) taking it a little further back into the 3000 degree range eliminated the filter's contribution to the red cast.
Find more about C.W. McGowen at: http://www.linkedin.com/in/cwmcgowen