Using a Sinar Fresnel Lens on an F or Norma Camera???

[neil poulsen]

I just received and have been experimenting with a Sinar, framed fresnel lens on a Norma, 4x5 camera. I've observed the following:

o The framed fresnel doesn't fasten to the Norma back. It appears to vertically rest against the ground glass. Once one presses it against the ground glass, perhaps a faint suction between the frenel and ground glass helps to keep it in place. It seems like it ought to fasten, though? :confused:

o The framed fresnel definitely brightens the image, and makes it easier to compose the image, but it's a little blurry. While one could focus using a loupe with the fresnel in place, it's much easier to focus without the fresnel.

Is any of this different using a Sinar F back? For example, do the Sinar, framed fresnel lenses fasten to a Sinar F back? (Seems like it ought to fasten?) Is the image through the fresnel lens any better on a Sinar F?

[RSalles]

Definitely it is. I forgot to swap the framed fresnel between my present F2 and the Norma which I bought and CLAded for a photog friend last year: the last stayed a couple of weeks for adjusting and I have had the opportunity to use it in the field and in the studio for some portraits.
What I really like about the framed fresnel in the F2 is the easy way to put and remove it for accurate focusing, it's a piece of cake, as far as you have a place to put it between both operations.
In a bright day, with a fresnel and a dark cloth I'm comfortable with lenses which max aperture are f9/f11, or more clear lenses with any filter.
To resume: for composing, the fresnel is much better - subjective, my own eval. - for acurate focusing, without the fresnel - for sure, no discussion, it's a fact. This happens with any camera, not only with the Norma or F/F2.


Cheers,

Renato

[neil poulsen]

Ranato, Thanks for your response. As it turns out, I purchased a 4x5 Norma recently and received framed fresnel that locks into an F/F1/F2 back. Interesting, it also "locks" well into the earlier Norma cameras that don't have the locking mechanism. To explain, it holds it's place via friction, but it can still be easily removed.