I've had in-camera flare problems using ultrawide lenses on large format cameras. When shooting at night, for example, a bright light source in the scene will reflect off a surface inside the camera near the edge of the film and cause fogging in that area. A bright sky or backlit scene will sometimes cause the same problem in the daytime. I solved this problem in my home-built 6x12 camera by gluing strips of black velvet inside (the velvet has much lower reflectivity than the matte black paint that had previously been sprayed inside the camera). Unfortunately, black velvet has thousands of little fibers that keep falling off once it has been cut. These tend to end up on the film, causing fatal pinholes. My Arca-Swiss 5x7 also needs flare proofing, but I want to find a non-fiberous substitute for the velvet. Does anyone know of any material with the same low reflectivity but without the little fibers?

-- Joel Pickford (pickimage@csufresno.edu), February 09, 1998

Answers

I'll bet that the velvet comes off at the edges. Try cutting the velvet to size and then singe the edges with a lighter or apply glue to the edges before applying it.

-- Tim Brown (brownt@ase.com), February 10, 1998.

a background paper product called Tufflok ( ? ) can be found at

-- al lewek (lewek@kwom.com), February 14, 1998.

a background paper product called Tufflok ( ? ) can be found at Studio Specialtiies in Chicago or thru your local Calumet store. Commercial photographers use this material for years. Comes in a number of colors plus black. Sold in long rolls - approx. 4 ft. wide.

-- al lewek (lewek@kwom.com), February 14, 1998.

Amateur telescope makers have devised solutions to this problem. They install long hoods over the aperture to block incoming stray light, install baffles (of thin aluminum) to block gross internal reflections from reaching the eyepiece, blacken any components/edges inside the tube, and then line the interior of the instrument with black "flocking" paper or matte board to attenuate other stray light. I can help you find sources for info or materials if you wish.

You may find that using a lens hood and touching up the matte black paint inside your instrument will suffice. I would be concerned that installing a soft material inside your instrument may become a maintenance nightmare -- fibers, fungus, damage to instrument from glue vapors, etc.

-- David Stokes (dstokes@texas.net), February 20, 1998.

You could use black flocked paper. This is paper with a velvet-like surface designed to absorb light. It is avaialable from Edumund Scientific with an adhesive, or non-adhesive, backing. Since it is designed for just the purpose you describe, I assume that "shedding" is minimized.

Catalog number P60,068...two, 27" x 36" sheets, non-adhesive back Catalog number P70,621...one, 20" x 30" sheet, adhesive back

Edmund Scientific (609) 573-6250

-- Chris Ellinger (ellinger@umich.edu), February 27, 1998.