8mm Forum: Unexpected difference between Elmo 1.1 and 1.0 lenses

This is topic Unexpected difference between Elmo 1.1 and 1.0 lenses in forum 8mm Forum at 8mm Forum.

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Posted by Adrian Winchester (Member # 248) on April 15, 2011, 09:04 PM:

I've just been running a film on my GS and something caused me to switch from a 1.0 to a 1.1 lens part of the way through. The film was printed a bit off-centre, meaning that a white line was visible along the right edge of the frame, if I kept the image within the border of the screen. However, much to my surprise, once I switched to the 1.1 lens, the white line more or less disappeared, as very slightly less of the frame was visible all round. Obviously, such a change of lens makes no difference to the gate, so I'm puzzled by this difference. Can anyone explain it?

Posted by frank arnstein (Member # 330) on April 16, 2011, 11:08 PM:

Hi Adrian,

I would think that the 1.1 lens would have a smaller aperture than the 1.0 & this may explain why your projected frame is fractionally smaller using the 1.1 lens.

Thats just a guess & more knowledgable members will probably be able advise us on this interesting lens query. [Razz]

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