Hi David,
Years ago I built an 8 x 10 enlarger out of an old 9" x 12" plate camera
(with no permanent modifications so that the camera could still be used as a
camera). I built a small platform for mounting the camera horizontally so
it projected like a slide projector. Immediately behind the camera was a
light trap seal of weather stripping and a wooden and masonite track that
held a hinged negative carrier--two pieces of plate glass (darkroom tape for
the hinge and to define the seating space of the negative.) The light
source was an oversized Aristo 12 x 12 cold light. The lens was a 12 inch
Nikkor process lens. The whole platform sat on a small Black and Becker
work table, which clamped on to a small board nailed to the bottom of the
enlarger platform. You could either slide the enlarger assembly back and
forth on the work table or move the whole table further from the wall for
making mural size prints. A focusing cloth was laid over the enlarger
during exposure to cover any light leaks.
You can use the same camera you are shooting with as an enlarger, and simply
remove the ground glass and put a plate glass carrier where the film holder
goes, but the advantage of a slightly larger camera and light source is
being able to print the full negative without any cropping. Although
enlarging and process lenses are best for enlarging, I've also know people
to use the same camera lens for shooting and enlarging. The sharpness may
not be quite as good, but it will work, and if you're using a large format
negative to begin with, the loss of sharpness may not be as noticeable as
you would expect as long as your prints aren't huge.
The main advantage to horizontal projection for me was keeping the weight
down and being able to disassemble the enlarger to store and move it easily.
One difficulty, though, is setting it up to keep the lens plane, negative
plane, and image plane all parallel. Use a plum bob to check and adjust the
plane of the negative, lens, and projection surface. Project a large half
tone pattern as a negative to visually estimate overall sharpness and the
"square" from left to right. Measure the vertical height of both the left
side and right side of the projected rectangle to adjust for keystone,
insure your corners are square, and that both sides have the same exact
dimensions. For enlargements 16 x 20 or smaller, I projected onto a tacky
surface that held the paper flat by putting spaced sections of 3M "post-it"
bulletin board material directly onto a flat wall. (A vacuum easel can also
be made by using pegboard masonite mounted onto a closed wooden frame fitted
with a vacuum cleaner.) For mural size prints I discovered the concrete
wall was not flat enough, so I built a large easel out of a light weight
hollow core door that I mounted on the wall. The paper was held in place
with masking tape. For mural prints, a focusing extension was made by
taping a circle of strong cord onto the camera's focus nob--the loop of cord
long enough to reach while looking through a grain focuser.
Good Luck.
Rick
[EMAIL PROTECTED]
> From: david <[EMAIL PROTECTED]>
> Reply-To: [EMAIL PROTECTED]
> Date: Fri, 01 Jan 1904 00:33:21 +1000
> To: [EMAIL PROTECTED]
> Subject: [Cameramakers] 4x5 enlarger - building yur own
>
> Has anyone on the list had experience with building their ownenalrger
> for large format work - I coul use some plans or just advice.
> David Oliver
> Bowral
> Australia
>
> _______________________________________________
> Cameramakers mailing list
> [EMAIL PROTECTED]
> http://rmp.opusis.com/mailman/listinfo/cameramakers
_______________________________________________
Cameramakers mailing list
[EMAIL PROTECTED]
http://rmp.opusis.com/mailman/listinfo/cameramakers
