Graflex.org Forum Index Graflex.org
Get help with your Graflex questions here
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Calotypes

 
Post new topic   Reply to topic    Graflex.org Forum Index -> Large Format Photography
View previous topic :: View next topic  
Author Message
KeithNP



Joined: 30 Nov 2001
Posts: 26
Location: Loma Linda, CA

PostPosted: Mon Sep 02, 2002 9:43 pm    Post subject: Reply with quote

Once again, questions about alternative printing processes:
1: are the chemicals used in calotyping (salted paper prints) likely to stain a fiberglass sink? I rent, and don't want to loose the deposit.
2: Are there any nasty gases given off during the process? I know Hypo stinks, but its not really dangerous... right? (my bathroom fan sucks , or more accurately, doesn't)
3: is it feasible to make a printing frame with a board, some piano hinge, a sheet of glass and epoxy, or is it smarter to cough up the $$$ for a real one?
any help greatly appreciated.
Back to top
View user's profile Send private message Send e-mail
Les



Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI

PostPosted: Tue Sep 03, 2002 12:10 am    Post subject: Reply with quote

Well I can't say much about Calotypes, what chemicals are used? Maybe that might jog my memory.

Printing frames are another matter. If you are committed to doing this then I say buy the frames (check ebay of course, they are for the most part cheaper than Light Impressions or Calumet on these things.

If you are just trying to get your feet wet, (or hands in this case then look into alt frames.

I once had to print some glass plates on Studio proof paper and then gold tone. There wasn't enough in the budget to buy a half dozen frames and I didn't have the time to do these one at a time.

I made my own frames, or to be more accurate, printing books. The base was masonite. To that I added a piece of heavy felt to give the neg some cushion. The top was a piece of 1/4" glass plate, cut raw and taped with aluminum "muffler repair" tape. This was used for the hinge as well. The masonite was split down the middle to act like the split back on a printing frame.
During the printing process I gaffer taped the glass to the back on each side near the hinge. Then one strip of tape on the side opposite the hinge.

This allowed me to untape the far side and look at the print, the other two pieces of tape held the print and the glass together so they didn't move.

Total cost was about $10 each. for 8x10
Back to top
View user's profile Send private message
bertsaunders



Joined: 20 May 2001
Posts: 577
Location: Bakersfield California

PostPosted: Tue Sep 03, 2002 5:50 am    Post subject: Reply with quote

A plastic garbage bag will protect the sink.
A hole over the drain, and a rubber stopper will facilitate the draining of liquids!
Back to top
View user's profile Send private message Send e-mail
Henry



Joined: 09 May 2001
Posts: 1446
Location: Allentown, Pennsylvania

PostPosted: Tue Sep 03, 2002 6:56 pm    Post subject: Reply with quote

Chemicals used in Fox Talbot's negative/positive and calotype processes included sodium chloride, silver nitrate, gallic acid (derived from tannin---the English drink a lot of tea), and bromine ("a heavy, volatile, corrosive, reddish-brown, non-metallic liquid element having a highly irritating vapor," according to The American Heritage Dictionary). If you're using that last one you may find a few extra holes in your sink. Silver nitrate stains indelible blue-black, NaCl is corrosive (ever drive through Syracuse?), and tannin?---try living downstream from a paper mill. It's a wonder those old-timers didn't kill themselves. The Daguerreotype process was just as toxic.

Last month in England I visited Lacock Abbey, Fox Talbot's home. Very interesting little museum there discusses thoroughly the chemistry of his processes. You can walk through the manor house and see the oriel window which was the subject of the world's first photographic negative. Negativo numero uno---think of it! Now we're up to 96.3 trillion and counting....
Back to top
View user's profile Send private message
KeithNP



Joined: 30 Nov 2001
Posts: 26
Location: Loma Linda, CA

PostPosted: Fri Sep 06, 2002 8:37 pm    Post subject: Reply with quote

The processes I've seen on the net so far don't use bromine or gallic acid. As far as I can see, I salt the paper, dry it, then sensitize with a solution of silver nitrate and citic acid. Dry in the dark, and then contact print under UV or sunlight. Fix with Hypo. The only obnoxious chemicals in the process are the silver nitrate and the hypo. I know silver nitrate is used to cauterize wounds in the medical field, so don't get it on your skin, and (as I said) hypo has a distinctive "aroma". Does hypo stain, or linger?
-Keith
Back to top
View user's profile Send private message Send e-mail
Henry



Joined: 09 May 2001
Posts: 1446
Location: Allentown, Pennsylvania

PostPosted: Sat Sep 07, 2002 8:27 am    Post subject: Reply with quote

Let's be clear about what a calotype is. The historical calotype of Fox Talbot, as described in Beaumont Newhall's "The History of Photography," was a radical modification of his original process. Quoting Newhall, "Previously he had allowed his sensitive paper to remain exposed to light in the camera until the image became visible. Now he found, as had Daguerre, that it was possible to give a much shorter exposure and yet secure a satisfactory image by after treatment. Although the paper was blank when taken from the camera, by development the image appeared as if by magic.
"He prepared the paper by bathing it first in silver nitrate and then in potassium iodide. The relatively stable silver iodide which was formed became, he found, highly light sensitive when he washed the paper with a mixture of gallic acid and silver nitrate, a solution he named 'gallo-nitrate of silver.' After exposure the paper was bathed again in the same solution which, acting as a physical developer, gradually brought out the image. To fix these negatives Talbot used at first potassium bromide and later a hot solution of hypo [sodium thiosulfate]. He printed them with his silver chloride paper."

You should consult the book "Health Hazards for Photographers," by Siegfried and Wolfgang Rempel (ISBN 1-55821-181-0), which details the effects of many chemicals used in photography. It makes for pretty scary reading. Hardly any are innocuous, and some are deadly.
Back to top
View user's profile Send private message
KeithNP



Joined: 30 Nov 2001
Posts: 26
Location: Loma Linda, CA

PostPosted: Mon Sep 09, 2002 12:16 am    Post subject: Reply with quote

Oh. OK. I had seen "salted paper prints" and "calotypes" used interchangeably. I'm interested in making digital negatives, and printing them in the sun or under UV - paper, salt, silver nitate, citric acid, lots of water, and hypo to fix. I'm looking for a minimum of chemicals, and no need for a darkroom. I know photographers formulary has a one-bottle cyanotype, and I'm also thinking about that.
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    Graflex.org Forum Index -> Large Format Photography All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group