I use WP, and was fortunate to buy a kit that contained 6 film holders. I love the format, and I need to use it more. My camera is a modified Rochester Optical Standard, originally a plate camera. Somewhere in its history, a skilled woodworker converted it to focus on film in Eastman holders. The holders had been modified with 1/8" shims on each side to fit the camera. It's not a perfect fit, but it's light-tight and produces sharp images.
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