Fresnel lens

[Thompsonr]

I have a Cambo Legend and I picked up a Fresnel Lens in a camera flee market that looks like the right boy for the job. Should it be fitted between the lens and the ground glass or should it be on the outside between the eye and the ground glass? It seems to fit and work in both places.

If it goes between the lens and the ground glass, can I be sure its not lifting the ground glass and therefore messing up the focus?

Either way I assume the rough surfaces touches the Ground Glass?

Thanks
Ralph

[Alan Davenport]

Apparently, there are some cameras that require the fresnel to go between the lens and groundglass, but Cambos are not among them. Put the fresnel on the outside of the glass, with the fresnel surface against the glass (this won't change the function of the fresnel but will help to protect the delicate ridges from damage.)

BTW, if you put the fresnel between the lens and GG, even without lifting the glass, it will still change the focus.

[ic-racer]

The Horseman FA 4x5 was designed with the fresnel between the lens and the ground glass, while the Horseman VH-4 6x9 was designed with the fresnel between the ground glass and the photographer's eye. With the fresnel between one's eye and the ground glass I think it is a little harder to focus because you are looking through the fresnel to see the ground glass (I usually need to use the central 'clear' area for critical focus). In practical use, focusing with both systems is similar.

[Thompsonr]

Thankyou for your help. The fresnel lens does seem to fit nicely between the eye and the ground glass under the two spring clips. Alan, I understand your last point, I hadn't thought about that before. I guess the Horseman refered to by Ic-Racer somehow compensates. Anyhow, I've fitted the lens and it works fine. Many thanks for both your responses.
Best regards
Ralph