<p>Zombie Glass Backs thread:<br /><br />The glass back option required 2 things (besides the glass):<br /><br />1: An F model (3.5 or 2.8) with the internal pressure tab to lock/unlock the flat glass, and a recessed pin located next to the right hand side film gate guide rail. <br /><br />2: The correct optical glass back with a raised tab on one side of the pressure plate; when the plate is set to the optical glass position; the pin pushes the pressure plate away from the film gate - to accommodate the optical glass.<br /><br />Regarding optical glass - the differences can be subtle, and vary with the subject (buildings with flat planes vs landscapes @ f16), aperture setting, etc.<br />Opinions vary as to whether the improvement is on the edge, center, or all over: <br />My own tests have so far been inconclusive. <br />In my limited experience, if the glass is clean & clear, it won't have an effect on images, or scratch negatives.<br>
<br />BTW - Rolleiflex backs are not universally interchangeable across all models: The later "White Face" film gate guide rails and corresponding film back's pressure plate are different than earlier versions: Using an older type of back will result in focus problems with a WF model: A post CLA field-test revealed this on my WF Rollei, and Harry Fleenor confirmed it. Exchanging pressure plates solved the problem.</p>
<p>220 most certainly can be used with Rolleiflex models having the 12/24 option:<br />Some people report success with hacks to use 220 on non-220 fitted bodies; usually non-invasive methods of fooling the counter.<br>
Note; there is no special setting on the film pressure plate for 220 - it stays in the same position as 120 - at least, that's the way my 12/24 equipped 3.5F works..</p>
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