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View Full Version : ? Fresnel lens for 11x14


Greg
18-Nov-2016, 17:55
Anyone out there use a fresnel lens with their 11x14? I use one with my 4x5 and love it. Have an OEM one with my 8x10 Sinar Norma but just doesn't seem to be as great to use in practice compared with the 4x5. Have been considering getting one for my 11x14, but wondering if larger the format - less a fresnel really matters or is even effective. Have never seen a manufacturer of ULF cameras offer fresnel lenses for their cameras. Is there a reason for that?
thanks
Greg
Tracy Storer
23-Nov-2016, 18:42
It depends on your ground glass. If your GG has heavy diffusion (coarser texture), you will have a dim, even image; if the diffusion is light (finer texture), you will have a bright image with a "hot spot" that moves with you as you move around viewing it. Fresnels are good for reducing the "hot spot" problem(which is accentuated with shorter FL lenses).

I have offered ULF fresnels for years, but have sold relatively few.
blindpig
6-Dec-2016, 08:23
My home made 11X14 camera has a fresnel lens for it's ground glass.I removed the lens from a rear projection TV,cut it down and lightly sanded the smooth side.It works swell, don't need a dark cloth unless the light is very,very bright.Don't know why camera makers don't offer them,for my part it's very helpful.
Mkillmer
15-Feb-2017, 21:16
My home made 11X14 camera has a fresnel lens for it's ground glass.I removed the lens from a rear projection TV,cut it down and lightly sanded the smooth side.It works swell, don't need a dark cloth unless the light is very,very bright.Don't know why camera makers don't offer them,for my part it's very helpful.

I have also used the fresnel from a rear projection TV. The TV was very inexpensive (and heavy!) but the fresnel is very high quality. The total cost was $3.
AlexGard
4-May-2017, 08:55
Hi Tracy
are you still selling 11x14 fresnells?
Dave Wooten
4-May-2017, 12:00
Got one from Tracy, I like it. 14 x 17.
Tracy Storer
7-May-2017, 15:10
Hi,
since starting to offer these several years ago, I have sold very few. But Yes, they are still available, I order them from an optical house and supply a CAD drawing so they can Laser cut them to my specs.
Email me directly from my website if interested.

Hi Tracy
are you still selling 11x14 fresnells?