gum advantages

HOLTSLANDER@sask.usask.ca
Thu, 17 Mar 1994 09:24:56 -0600 (CST)

DATE SENT: 17-MAR-1994 08:42:20

>What is a polaroid transfer? The winter issue of View Camera mentions that
>process and I have some polaroid film ...

A polaroid transfer is the technique of transfering the image created by a
polaroid negative onto something other that the recieving paper in the polaoid
pack. The image is usually tranfered to a good paper, giving the image a
slightly different look. The image can also be more easily manipulated once
transfered to the paper. This process only works on the peel apart films not
the instant color processes (SX 70 and the like).

The positive image in the peel apart films is made by having the unexposed
silver from the negative diffuse onto the positive recieveing sheet. Easy
to say but quite an accomplishment chemically. I beleive that the positive
recieving sheet is chemically inert, it just an ordinary piece of paper,
therefore it is possible to make the transfer onto a wide variety of media,
most use paper of fabric.

The process appears to be simple. Ive not done it, only read about it.
To summarize quickly. The paper to be transfered to is dampened. The polaroid
pack is exposed. It is allowed to develop about half the reccomended time.
The pack is peeled apart. The negative is placed face down on the prepared
paper. The negative is firmly pressed against the paper using a roller.
The negative is removed.

I think most people who do transfers use the polaroid to copy an existing
image. There are many different sizes of polaroid medium format 4x5 and
8x10.

Polaroid has produced a very good publication of Polaroid transfers. If you
ask for it they will send it to you for free.

I have played around with 4x5 polaroid. I have a polaroid back for my 4x5.
I have tried to make a pinhole camera to use the type 50 series of polaroid
film. I have found it is possible to process this film by placing it on my
kitchen counter and with firm pressure roll an old rolling pin over the film
pack. This breaks the pod and spreads the chemistry fairly well, but not
perfectly.

For my pinhole polaroid, I made a slot for the film with a light seel and
a latch for releasing the the paper dark slide. I have had little success
and run out of old polaroid (its a little expensive for trail and error stuff)
Has any one else tried anything similar.

Another Polaroid product that sounds promising is Polachrome film. This
is Polaroids slide film. It is quite different from all other slide films,
in that it is an additive color process. The film is made up of a fine
grid of primary colored filaments in film. I don't recall the details of
the process. The image is made by the interaction of ultra fine filaments
to make a color image. The image has been compared to the early Autochrome
transparencies made by the Lumiere brothers at the turn of the century. The
physics of the processes are the same. The results are a very soft color
image. This would likely be the ideal transparencies to make color
gum bichromates from, though it will be quite a while before I try color
gum. A good refernce for this process is the book "Everything Photographic"
I can look up the exact reference if anyone is interested.

Other polaroid references are Ansel Adams book on Polaroid, and the book
"Lands Polaroid" the latter is more a histroy of the company, but it does
explain the processes in understandable terms.

>Now that I am on the air, I would like to ask those who use it why they have
>decided to use the various gum processes? Is there something extra that that
>process offers?
>
>Thanks
>David Green.

The reason I am using the Gum Bichromate process, is that it is relatively
cheap, the basics are straight forward and yet it is allegedly capable of
producing fine images (I haven't made any "fine" images yet.) You are
also capable of making a lot of modifications to the image through a variety of
techniques. Its cheap, relatively easy to do and quite flexilble. It is
probably one of the easiest alternative processes to begin with, though I
think it takes consideralbe skill to master. The trick to gum printing
is that there are so many different ways of doing things, so many
variables that will be specific to your own situation that it is impossible
for guides or handbooks to tell you exactly what you have to do to get
good images the first time you try it. It takes a certain amount of
fiddling and it is not a fast process. Other than that it is quite easy
to use.

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Gord Holtslander Department of Biology
HOLTSLANDER@SKYFOX.USASK.CA University of Saskatchewan
Saskatoon, Saskatchewan
Tel (306)966-4433 S7N 0W0
Fax (306)966-4462 Canada
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