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The glass cover plate is scratch resistant and
anti-reflective coated on both sides. This gives maximum light
transmission and back light reflection suppression. This choice
is ideal for studio and location work, greatly reduces the
eyestrain on complex set ups and long working hours. The above
description fits what we call Type 1 cameras, i.e those cameras
that originally had a ground glass screen only, or a ground glass
screen plus a separate fresnel between the glass and the eye. The
Type 2 cameras (for 10cm x 12.5cm cameras only) are those having
a fresnel lens between the taking lens and the ground glass
originally. We provide a part called Acrylic Set Back for these
type cameras. This clear acrylic part substitutes for the
original fresnel and provides the necessary mechanical thickness
and optical set back to focus the image to
correspond with the
film plane in the film holder. The focussing screen and cover
plate are then used as described (see copy of the
"Installation Guide", which describes this in more
detail).
The Intenscreen can be ordered
either plain (no markings), or with grid lines (1cm grid
with open centre) and
crop markings (heavy
lines, for cropping, 6 x 7, 6 x 9, 6 x 12 format markings).
The main grid lines are
.006" to 0.010" wide. Lines appear black when viewing.
The following list the two types of
camera:
TYPE
1 CAMERAS
Calumet, Sinar,
Deardorff, Zone VI, Graflex, Speed Graphics, Dr. Phillips,
Linhof, Cambo, Graphic View, Techihara, Nord I & II,
Inka,
Wisner & Plaubel.
TYPE
1 - Installation Arrangement
TYPE
2 CAMERAS
Toyo, Horseman &
Polaroid MP 3, 4, 5
TYPE
2 - Installation Arrangement
Almost any camera can be fitted
provided accurate dimensions are taken for the acrylic set back,
the focussing screen, and any cover plate. As a rule, a minimum
of 1/32" clearance between the wood or metal holder and the
screen is necessary for expansion and contraction.
EXTRA
FRESNEL LENSES
A final optional part can be
provided for short wide angle lenses such as the
"Superangulon" by Schneider series. This extra fresnel
lens, when attached in place of the outer cover plates or on top
of them, will give a clear corner to corner view of these lens
images. This part is shatter resistant. This part is recommended
when using these wide angle lenses, especially if the Schneider
centre filter is in use to compensate for the light fall off
inherent in this type of lens.
The combination of the Intenscreen and the extra fresnel will greatly improve the viewing of
the wide angle lenses.
When a wide-angle taking lens is
used in a view camera - 4" x 5" , 5" x 7",
8" x 10"- a clear fresnel lens must be used to remove
the vignetting at corners. For a 4 x 5 view camera, a
clear
fresnel (0.060" thick) will be needed. For a 5" x
7" or 8" x 10" view camera, a clear fresnel
(about 0.080" thick) will be needed. The clear fresnel lens
will replace the anti-reflective cover glass. The size of a clear
fresnel lens is the same as that of the AR glass.
1. Any lens with a focal length
shorter than 150mm (6") is considered as a wide angle lens
in 4 x 5 cameras.
2. Any lens with a focal length
shorter than 200mm (8") is considered as a wide angle lens
in 5 x 7 cameras
3. Any lens with a focal length
shorter than 250mm (10") is considered as a wide angle lens
in 8 x 10 cameras.
Installation
Position of an Extra Fresnel Lens
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