Fresnel Lens Screens for Large Format Cameras
Fresnel Lens Screens for Large Format Cameras
These Fresnel lenses are designed to be installed so that the grooved side of the Fresnel is touching the outside (shiny) side of your ground glass screen. This is not a focusing screen.
Please see the chart in the second photo, and the drop down list, for the full selection of Fresnels I have available.
My Fresnel lenses have been selected to provide the following benefits:
Increase in apparent brightness and more even illumination over the frame. Corners are visible without needing to hunt around the frame, meaning time under the focusing cloth is better spent.
Fine grooves. The fine groove width allows ease of focus through the Fresnel with a loupe.
Protection of the ground glass. 1.5 to 2.0mm thick acrylic material.
Each Fresnel comes supplied in a tin, or shockproof plastic, case. Ideal for you to store an emergency ground glass screen.
*N.B. Ideally, a Fresnel lens screen works best when the focal length of the Fresnel roughly matches the focal length of the lens being used. In the table (photo 3) I have added +20% to the focal length of the Fresnel to mark the upper limit of the optimum range. Lenses of a shorter focal length can of course be used, however the brightness-boosting effect will become less noticeable the wider the lens is. If you have a specific question, please get in touch!
Please allow 5 days for packing and postage.