Does the lens collar rotate to a 180 degree position? (In 35/70 projectors, the lens needs to be centered on the film frame for 70mm mag and offset for 35mm optical to accommodate the soundtrack) This would be a side-to-side offset.

If you remove the lens from the projector lensmount, the collar usually will have three set screws around the outside near the center of the collar that are used to tighten the pressure plates that hold the lens. These can sometimes be used to adjust how the lens is centered in the collar and, thus, on the screen. Just loosen one and tighten the other two to nudge the lens. >>Do this at the workbench, so you don't drop the lens! << Put it back in the projector and see what happened. Take note, however, that if the collar is slid forward or back on the lens, it will significantly change the focus, and you want both lenses to be at the same focal point so you don't have to adjust too much after a lens change (especially if it's during a show).

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How far is it off?

(If it's only off a little) I have found some of those 5" to 2 25/32" lens bushings are machined poorly. Sometimes by rotating the bushing, you can get it to hold the scope lens in the same plane as the flat lens.

With the shorter focal length lenses used nowadays, I've seen where the lens has to be positioned so close to the film, that only the front 1/2" or so gets clamped into the bushing; which means it doesn't get clamped "straight." They sell screw-on lens extention collars for that.

(If it is off a lot) On some projectors (Simplex) you buy one bushing for 35mm use and another for 70mm use. They both are 5" to 2 25/32" bushings, but the hole in the 70mm one is offset to center the lens for 70mm film. Usually the 70mm bushing is painted red, but I got one that wasn't.

If I remember, the bushing that comes with a DP70 was a type where one screw clamps a "C" shaped section inside the bushing.

I agree that the printer can introduce a vertical shift (especially bi-directional printers), but that wouldn't be particular to scope vs. flat. And Super-35 extraction to scope would depend on the setup by the optical printer operator.

The guy who did them messed up and just reframed and adjusted the turret to compensate. I checked it by shutting down the projector and looking into the aperture. There WAS a framing difference between F and S!