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View Full Version : Cutting and fitting a Plastic Fresnel Lens



Greg
9-Nov-2015, 18:01
Finally have acquired 2 plastic fresnel lenses for my Whole Plate and 11x14" view cameras. Both fresnels are oversized so have to be cut to working sizes. Both cameras are Charmonix (wooden backs). I have yet to figure out the best way to secure the fresnel lenses to the back standards.

2 questions:

1. How to cut plastic fresnel lenses? Which side is best to cut into?

2. How to mount the fresnel lenses? Any hints or ideas will be very welcome.

thanks

Greg

Bob Salomon
9-Nov-2015, 18:14
If I had to cut them I would go to our local plastic supply/fabrication shop and let them do it properly for a minimum charge. I would mount it to the eye side of the gg with some good, clear, double sided tape in the corners.

LabRat
9-Nov-2015, 18:42
Cut them the way you would cut a sheet of acrylic... Use a plastic cutter knife (or Xacto with more scores), and score it until about half way through the material, then rest the sheet on a piece of wood (as a step), and one over it to clamp the sheet, then press on the cut-off part with another strip of wood to break it off evenly with even pressure... Cut into the groove side so the base breaks evenly...

If thin and flexible, a paper cutter might do it...

Steve K

vinny
9-Nov-2015, 19:10
I've cut them as labrat describes and with a band saw. The band saw produced a smoother result w/o any chips.

LabRat
9-Nov-2015, 19:55
Oh, and don't forget to keep the center of the fresnel centered by cutting off the equal amount from the two sides, and top/bottom...

Steve K