[Leica] Slide Projection Lens Basics

[Marc James Small <msmall@roanoke.infi.net>]

Leica makes a range of slide projector lenses.  These are available in two
different mounts, the older P mount shared with most, if not all, of Leitz'
and Leica's earlier projectors and with the current P2002, and the newer P2
lenses used by the P150, P300, and P600 projectors.  The two families are
optically identical and vary only in the mounts for the lenses between 60mm
and 200mm in focal length;  the P series includes lenses both shorter and
longer than this, though, including such specialty items as the 35mm f/2.8
Elmaron -- talk about being able to show slides in a phone booth! -- and a
300mm f/4.3 Epnor which would be suitable for projection down the nave of
the Cathedral of St John the Divine.  There are also two zoom projection
lenses available in both mounts.

For normal purposes, the shorter the focal length, the shorter the distance
necessary to fill an entire screen.  A 35mm lens will fill a screen at a
remarkably short distance, 7 or 8 feet.  In America, where rooms are a bit
larger than in Europe or Asia, slide projectors often come with 100mm or
longer projection lenses, but in Europe, the land of apparently small
rooms, an 85mm or 90mm is normal.

(And how many of you guys remember the lamented Prado Universal for which
the 2.8/35 Elmaron-P lens was introduced in 1968?  There were attachments
for hooking microscopes or test tubes up to the Prado Universal projector,
so that an instructor could sit with a student at his or her desk and
project the results onto a screen immediately in front of them.  I owned
one, once, and stupidly sold it -- it was one of the neatest Leica toys
I've every had.)

The P150 comes with a so-so, not-good, not-bad 85mm f/2.8 Hektor-P2, but
this can be, and really should be, replaced with the much more satisfactory
90mm f/2.5 Colorplan-P2, for glass-mounted slides, or the Colorplan-P2 CF
(curved field) for cardboard-mount slides.  An even finer optic is
available in the 90mm f/2.5 Super-Colorplan-P2.

I do not have a current Leica pricelist in front of me, but I would
guesstimate that the Colorplan lenses are available for under $200 and the
Super-Colorplan around $325.

Medium-format projectors are a step beyond this.  There, the normal
projection lens is around 180mm or so in the US, 150mm in Europe.  (And,
stunning as a 35mm slide can be, a "superslide" (4cm by 4cm) is even
better, and a 6cm by 6cm slide MUCH better.  Fall is coming -- and my
Rolleiflex and I will be firing off some E100S of those turning leaves.)

Marc


msmall@roanoke.infi.net  FAX:  +540/343-7315
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