So this probably only applies to about 3 people on planet earth who care, but I’ve read here (and elsewhere) about problems with the rotating backs on the 4x5 burke & james press cameras leaking light, but just discovered that of the 3 variants I have, one has a fatter area between the groove (in which the thin ridge of all 4x5 holders fall into) and the outside edge of the camera, so with most modern film holders, their topmost “bump-out” rides up on that, leaving the film open to light leaks. Older holders that are flat from the ridge to the top (where the slide is) or have slightly larger areas before the top bump-out, settle in and work fine, no light leaks.

Anyway, something to be aware of if you happen to use one of these great little press cameras. Hopefully the crudely marked up pic makes it more clear...Click image for larger version. 

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