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anthony marsh
30-Mar-2010, 08:27
I'm new to LF and need help with this.I recently bought a Graphic View and found a fresnel screen in the carrying case but don't have a clue how to use it.Is it used in conjunction with the ground glass? If so is it in front or in back of the ground glass and which side textured or smooth faces which direction?

lloyd
30-Mar-2010, 08:33
on top of the GG smooth side out.

anthony marsh
30-Mar-2010, 15:01
LLoyd,thank you.The fresnel makes viewing brighter.I'm amazed at how many people in this forum are so willing to help newcomers like myself,Tony

RichSBV
30-Mar-2010, 22:18
The factory installation of the "Ektalite" (fresnel) screen is for the Ektalite to be closest to the lens when assembled with the grooves facing (touching) the frosted side of the ground glass.

Looking at it from the back as you would focus, you would have the ground glass clear side - ground glass frosted side - Ektalite grooved side (touching GG frosted side) - Ektalite clear side - air to bellows and lens.

You can get both the instruction manual and service manual (explaining this) at:
http://southbristolviews.com

Scroll down the menu on the left to Graflex Manuals and look on the right for the pdf files. The assembly of the back is on page 9, section 42 of the service manual (pdf page 11).

Ivan J. Eberle
30-Mar-2010, 22:56
The problem being, if it was originally designed for a fresnel but someone has installed it in the wrong sequence, your film plane may not correlate to the GG focus point, e.g. may not be installed at the correct distance. If that be the case all your carefully focused images will be out of focus-- on film. If you indeed have an "Ektalite" screen, it belongs in a sandwich with the fresnel screen to the inside.

But this being a Graphic View, it might pre-date that option and have come with a plain ground glass.

Also possible in the intervening 70 years that someone may have just acquired a generic fresnel to place over the top of a shimmed plain GG, outside (a placement where adding a fresnel is not critical to the focus). This could have occurred regardless of whether or not it originally came with an Ektalite.

Another way to determine if your GG is in the right place is to measure the depth of the GG compared to the flat surface of the film gape that it's recessed into. A plain GG reading should be something very close to .190" on any "modern" back that uses standard film holders. (The dimension for holders themselves is .197 without film in them.) If you're more than a few thousandths off in either direction there's a problem.

ic-racer
31-Mar-2010, 06:30
You need to determine if you have the appropriate frame to hold the fresnel in front of the GG (frame 03411-P2 or 30411-P3).
If not sure, leave it out of the system for now.

lloyd
31-Mar-2010, 06:55
good corrected info, I'm obviously not familiar with the graphic views........

anthony marsh
31-Mar-2010, 13:33
More good information,thanks to all,Tony