Large Film Holders

Grafist@aol.com
Wed, 12 Feb 1997 11:32:56 -0500 (EST)

Large Format Filmholders. O.K.Mac. I knew it would catch me up....I've been
so busy!

<There was a thread on this list several months back on
< home-made cameras (I think the phrase was "DIY cameras"). DIY
< film holders were included.
Its surprising what you can make with a few sheets of good quality (1mm
thick) mount board i.e.cardboard, but it must be the kind which does not
separate into thin layers and peel appart as you are working. Use a very
sharp scalpel type blade and a STEEL STRAIGHT EDGE which may be held in place
as cutting takes place, with LARGE thumb tacks (not the little ones used for
pinning up notices). The sheet material used for making dark slides does not
need to be strong enough to withstand a bomb blast and can be reinforced with
black "gaffer" tape along the multiple layered edges.
It takes a fair amount of practical trial and error before you can"
mass produce" the slides but after measuring out the areas required to be
cut you can make a template from thin rigid laminate (Formica) containing all
of the measurements defined at the corners by small holes drilled (using
miniature craft drill ).
After several hours I managed to get something consisting of five
layers glued together with instant IMPACT adhesive. START OFF with the
sheet size of the film you want to keep in the holder and design around that,
remembering that the lip of the retaining edge needs only to be about 3mm for
the film and 6mm to enable the sliding dark slide to be light tight.
After you have produced your first slide you realize why they cost
so much, commercially. But, even these plastic and metal babies at about $50
to $100 each go wrong, sometimes ( the slides break and crack) and they are
not flexible, which the cardboard ones are, which enables them to be held
ABSOLUTELY flat against the surface edge of the camera (which has velvet
glued on) .
Just in case anyone is interested....here's the posting re.DIY c/b
cameras.......
12/9/96
"...............results which left me amazed for days because of the very
slap dash way the camera was constructed producing a print which I swear
could not be distinguished from the results from equipment costing many
hundreds of pounds or dollars.
The ULT camera Mk. 1 was based on a Jacob^s "Cream Cracker " biscuit
packing box container for 24 X 300g packs.Box Code No. 30394. The box is 51cm
Long. 9 1/4" Wide and 11 1/4" Deep. The four flaps at each end fold up to
provide a mount base for the lens at one end and flaps at t^other end folded
inside to give a tight fit for cardboard film/paper negative base. The
negative material is loaded in a darkroom and secured with low stick tape. A
lid could be made from cardboard to fit over the back altho I used a black
cloth because of my impatience. The lens is composed of two meniscus 1
Dioptre(1000 mm) lenses available in glass or plastic from optician
suppliers. Mine cost approx $ 4 each. The two together give a focus of 500
mm placed like so: - ( ) . with a thin strip of tape round the edges to
hold together. The aperture was a piece of c/b with a pencil width hole
poked thru it.(approx f 80) All taped together, after making fine adjustment
with spring steel ruler of the distance from negative plane to front of lens,
the shutter( lens cap) on this Mk 1 version was nothing more than a piece of
black tape over the lens opening. Constructed in less than an hour I was
ready to test with a guessed exposure of 5 secs counted ( one little
elephant, two.....etc.) with the camera weighted down with a house brick on
the roof of my car in the road outside my house. The weather that day was not
particularly bright but not dull. Typically British lightish grey sky. Using
a sheet of Ilfospeed glossy Grade 2 Resin Coated I obtained a negative with
very fine detail and tone gradations in the clouds which I had not even
noticed and the print contacted under glass and developed in Phenidone
HydroQuinone (P Q ), same as the negative, showed very fine detail with no
trace of paper fibre. The success of this slapped
together box encouraged me to go further with refinements into Mk 2 and Mk 3
which incorporated a salvaged shutter from a 35mm Voigtlander (lens removed)
the opening in the shutter was more than adequate to give workable apertures.
I have since collected cheap broken down old cameras just for the shutters.
Mk.2 incorporated a viewing screen made of 2mm plexiglass (Perspex) and
facility for sliding DIY neg holders into place. D o I t Y ourself
holders are made of 1mm thick mounting board. I made a template from 1mm
Formica sheet with holes drilled accurately at the corner points where you
cut through the board using steel ruler (also pinned down with thumb tacks
whilst cutting) and very sharp blade so as to ensure complete accuracy. Using
hardwood strips fitted at viewing end with light trap edge surfaces lined
with velvet tape glued on, the neg holders slide neatly into place. One
holder has a permanent plexiglass screen dulled up with domestic scouring
powder (Ajax or Vim) to allow for positioning of the subject. The Mk 1 & 2
is only good for landscapes whereas the Mk 3 has a sliding focusing light
tight body plus a hooded magnifying system to replace the traditional cloth.
All made of cardboard. I made a special wooden tripod with a 12" X 18"
table and 60" legs which when splayed appart and held with thin rope, and a
tight stirrup held down by the foot to the ground, provided great rigidity
for long exposures. The tape used throughout is called Gaffer Tape. About
$7.50 per roll used for sealing all corners, edges etc., from light.
Several skilled cabinet maker friends suggested constructing
the camera from sheet plywood. "It would be a much more substantial
article......." Yes, but you can drop the "Cream Cracker" box from a
skyscraper or a mountain. Stick it together again in half an hour with Gaffer
tape and continue to capture masterpieces. The dropping is NOT an essential
part of the system. If anyone wants to contact me
should you embark on the project I will be pleased to advise on tricky
details via private email or list postings, as you go along. 16" X 20"
version is just a matter of scaling up and finding a box to do the job.The
same lenses could probably be used with the enormous coverage they have. The
film/paper negative holders would work just as well in the larger size
provided care was taken with cutting and glueing the bits together.Impact
adhesive, BTW, but for schools you would prefer something less toxic, of
course.
I was thinking of a 16" X 20" myself. Will
keep you posted on the results of my searching. Jacob^s Bakery kindly sent
me 20 folded flat 30394 boxes by special articulated lorry when I requested
them thru the P.R. Deptartment back in 1993.
Best wishes in your endeavours.
John.......... ftgrfst"