Re: [Leica] Re: Focussing cine-camera lenses

["Steve LeHuray" <icommag@toad.net>]

> Recently there was some discussion on the LUG concerning the focussing
> techniques used with cine cameras, and the fact that lenses were
> scale-focussed to pre-measured distances.

I guess I missed that discussion
>
> If any LUG members are involved in the cinema industry, could they
> tell me:

Went and dug out a Angeniux 16-44/T1.3 to help me answer your question


> If the lenses are manually focussed to preset distances, does that
> mean that the focussing is engraved to be read by someone standing in
> front of the lens, rather than by someone standing behind the camera -
> i.e the distance values are engraved 'upside-down' compared with those
> on a 35mm still camera lens?

Yes many times, but not always, cine lens are preset to a certain distance.
This is done by putting gaffers tape cut with scissors, on the lens barrel.
Then when shooting a scene the AC (assistant cameraman) turns the lens to
match the preset focus. Many, if not most pro cine cameras, have an
elaborate follow focus system mounted on the camera but still use the
gadders tape for setting any preset focus. These follow focus systems are a
gear set up that fits into the teeth of a ring on the lens barrel and then
there will be a small wheel to turn it and there will be a large white disc
where you can put the gaffers tape. This apparatus is part of what is called
a 'studio rig'.
>
> Do cine lenses have depth-of-field markings similar to those on
> still-camera lenses?

Yes they do but most critical focus (for feature films) is done with a
measuring tape. Documentary and cinema veri te' just go with whatever focus
they get looking through the viewfinder.
>
> The reason for these questions is that I have an old lens can be
> screwed into a Leica, but which has no DOF markings, and has a
> focussing scale engraved to be read from the front.

Do not know what that is.
>
> Given these odd features, I'm wondering if it may have been a cine
> lens which has been adapted for use on the Leica.

Probably not a great idea.
>
> Regards,
>
> Doug Richardson

Steve
Annapolis
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