ADDING DE TO SAND FILTER

Zweidel's question about Lens Flare in IR Photography intrigued me so much that I decided to run this little experiment. (EXIF data is for the top left photo).

The top left photo has severe lens flare and it appears to be coming from two or more sources. I have severe lens flare on the bottom Right near my left hand and moderate lens flare in the center of the photograph, and a little bit at the far left edge.

Top right: Even though the sun is behind me, you can see that I had direct sunlight hitting the bottom of the IR filter due to the fact that I have it tilted up at a significant angle. This appears to be the source of the worst part of the lens flare. Now for the lens flare in the center ... there appears another light path direct from the sun in addition to the one at the lower right side. The Bottom Right Photo shows how the second light source is entering the optical path. Intense IR light is leaking into the optics between the IR filter and the lens striking the back surface of the IR filter. This back surface light leakage appears to be the source of the lens flare in the center and edge of the Top Left photo.

The Bottom Left photo was taken under the same conditions except I used a 9"x12" envelope in my right hand as a lens hood and held it above the camere so no direct rays of sunlight hit any optical surface ... neither front or back surface ... and the lens flare is gone.

PS: How do you like my "dark shades" and Red & White print shirt in the IR spectrum.

Kodak color infrared film (EIR) was used here and processed in E-6 (normal). The film is quite grainy. This was shot with a normal lens. I thought the roots added an unusual quality. This film is no longer made. It was a very expensive film and required a special lens filter and loading in total darkness - however, it will be missed.