Do It Yourself Build Your Own Recessed Lensboards
Tom Fuller, April, 2000

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Carefully measure the front standard of your camera to
determine the overall size of the lensboard and make a
full-size drawing of it before cutting the foamcore. Note
how the original lensboard is held in place and mark where
notches and grooves will have to be cut to clear toggle
mechanisms, clips and corners. Also measure the inside
of the bellows and plan the recessed portion, or well,
to be no larger than 70 percent of these dimensions and
no deeper than 11/2”. Even if it physically fits
into the opening, an oversized well will interfere with
the bellows pleats when perspective control movements
are used.
Photos © 2003 Tom Fuller, All Rights Reserved
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For our project this month,
we will be making very inexpensive recessed lensboards for large format
cameras. As a commercially-made board of this type easily goes for over
$100 and our homegrown version costs about $10, I especially want to
point out its cost advantage as well as the simplicity of materials
and assembly. The project can be done easily in an afternoon by anyone
with a modicum of do-it-yourself skill and classifies as a Level 1 undertaking
as defined below.
My new Do-It-Yourself Level Scale refers to the tools and skills needed
for Shutterbug projects. Level 1 can be done using only items found
in the typical home by those able to follow detailed instructions, with
the successful assembly of a plastic model kit being a good reference
point. Level 3 requires “home improvement” tools, such as
a soldering iron or power drill, and enough hands-on experience to replace
a wall thermostat. Level 5 is for readers with serious toolboxes and
an equal degree of technical savvy, such as those who replace their
own brake pads. Few of my projects reach Level 5, and all will fully
detail any special parts or materials that may be needed.
A recessed lensboard simply places the rear element of the lens closer
to the film plane. It is used when the front and rear standards of a
view camera cannot be moved close enough together to infinity-focus
a short focal length lens. This is often the case when a pleated (rather
than a bag-style) bellows is used, as the folds become too thick when
completely compressed. Even when a bellows does adequately compress,
a recessed board may still be needed to let the bellows extend slightly,
thereby freeing up a few pleats, to permit minor perspective control
movement at the front and/or rear standards.
Our material is 3/16” all-black (both sides and interior) foamcore,
available at office and art supply stores. It comes in a variety of
sizes from several manufacturers, but one sheet of Hunt’s 20x30”
Sturdy Board ((800) 879-4868; www. hunt-corp.com) will do. However,
don’t toss the leftover pieces, for you’ll find a host of
other uses for this strong, lightweight material. While wood may seem
the “proper” choice for large format accessories, foamcore
has the distinct advantage of remaining virtually warp-free during construction
and use. It’s also exceptionally easy to cut by hand and needs
only white glue for assembly.
Because a picture is truly worth a thousand words, I’ll let the
accompanying photos guide you through the procedure. Remember that this
design can be used “in reverse” to make an extension lensboard,
placing the rear of the lens farther away from the film plane, to focus
long focal lengths on cameras with short bellows extension or to add
closer focusing capability. The size of the board and the manner in
which it is held onto your camera will vary widely from the one shown
here, so be prepared to add a good amount of ingenuity to this basic
design.
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Foamcore is remarkably strong
and durable if properly glued and taped. Although all-black foamcore makes
for easier light-proofing of the finished lensboard, I made this one from
the white and gray version to better show structural details. Measure
the shutter mounting thread before boring its hole in case it differs
from the now standard Copal No. 0, 1, and 3 sizes. You may need to glue
thin sheets of model airplane plywood (available from a hobby shop) to
the back and inside bottom of the well to make harder surfaces onto which
to tighten the jam nut and shutter housing of a heavy lens. All edges
must be cut straight and even (a sharp art knife and sturdy steel straightedge
are a must), glued securely and covered completely with black photo tape.
Coat all exposed foamcore with white glue to seal in loose particles.
Light-proof the board with two thin coats of flat black paint on the inside
and one on the outside, then topcoat the outside with Krylon or other
protective spray. A Dremel MultiPro rotary tool and No. 561 bit ((800)
437-3635; www.dremel.com)
is great for cutting the mounting hole, and while this step can be done
with a knife, this miniature power tool system makes it and countless
other do-it-yourself operations a snap. Whether cutting manually or with
power, practice first on scrap to develop a steady, confident hand.
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Foamcore is remarkably strong
and durable if properly glued and taped. Although all-black foamcore makes
for easier light-proofing of the finished lensboard, I made this one from
the white and gray version to better show structural details. Measure
the shutter mounting thread before boring its hole in case it differs
from the now standard Copal No. 0, 1, and 3 sizes. You may need to glue
thin sheets of model airplane plywood (available from a hobby shop) to
the back and inside bottom of the well to make harder surfaces onto which
to tighten the jam nut and shutter housing of a heavy lens. All edges
must be cut straight and even (a sharp art knife and sturdy steel straightedge
are a must), glued securely and covered completely with black photo tape.
Coat all exposed foamcore with white glue to seal in loose particles.
Light-proof the board with two thin coats of flat black paint on the inside
and one on the outside, then topcoat the outside with Krylon or other
protective spray. A Dremel MultiPro rotary tool and No. 561 bit ((800)
437-3635; www.dremel.com)
is great for cutting the mounting hole, and while this step can be done
with a knife, this miniature power tool system makes it and countless
other do-it-yourself operations a snap. Whether cutting manually or with
power, practice first on scrap to develop a steady, confident hand.
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