CIBACHROME PRINTING

Arthur Mc Kee (Area 26).

The C.R.C. should live up to it`s name and show how good positive to positive colour prints can be. All colour slide makers should make them. Anyone who can process E6 slides will find Cibachrome dead easy. Some slides which are so-so as slides produce very good prints. It is also possible to change the mood of the slide in the print to it`s advantage. So I think there should be more about reversal colour printing in the Club`s Newsletter.

To put my money where my mouth is I have written two short articles on Cibachrome and also donate a book for the C.R.C. Library, "Complete Guide To Cibachrome Printing" which is the best book on the subject I know. One of the authors, P. Krouse, had a lot to do with the introduction of Cibachrome-A in the States and was at one time President of Ilford Inc.

The Dagneureo type of the fist days was a direct positive process. Reproduction could only be made by re-photographing. The copies were unfortunately much inferior than the original. This remained with reversal processing until recently. Now materials are available which allow copies to be a near match to the original. Remember prints from slides are a re-photographing job. As a result many people are using their original slides as a master to produce copy slides and prints. If such a slide is a master to be only used in this way, why not make it in such a way as to give the best copies? Say to reduce contrast by flashing or special processing. Weighers & Mixers should be able to get a purpose out of doing this.

Bictanol Chemical supply a Cibachrome developer additive which can be added to any B&W print developer for processing Cibachrome, whilst full contrast masking. Club members could use it to devise a multi contrast developer for Cibachrome to give improved results.

5" x 7" CIBACHROME PAPER

Most of us know of the ISO system of `A` stationary sizes where the next smaller size is obtained by halving with the relative proportions of the slides remaining the same. There are indications that photographic paper may conform to this standard in time.

What many may not know is that 5" x 7" is such a halvable format which is available now. When halved it produces two 3 1/2" x 5" prints which is the standard En-print size. Halved again and we have 2 1/2" x 3 1/2" a standard cut film format and the most popular snap-shot size in "Box Camera Times" worth reviving now as an economic hand-out with a novelty value as a shirt pocket mini print in these days of maxi sizes.

Halved the other way 5" x 7" gives two 2 1/2" x 7" wide-view prints which can suit some subjects. I agree with Rita & Major Pearle when they state in their excellent article on "Making An Exposure Frame" in the issue No. 44 that it is best to use such a device to produce small prints on a single sheet of 8" x 4" paper and then to cut it up in full light after processing. I suggest however that for those who feel that they will never need to make a full 8" x 10" print there are advantages in using 5" x 7" sheets instead. With most 8" x 10" processors it is not much more difficult to put in two sheets of 5" x 7" as one 8" x 10". This is so with the very good Paterson Orbitor which the Pearls use and is now the only price economical 8" x 10" motor driven processor.

3 1/2" x 5" is not much smaller than 4" x 5" and better suits full size 35mm format. 50 5" x 7" sheets costs less than 25 sheets of 8" x 10". There is also a saving in Chemicals. 55 - 60 cc instead of 75 - 55 cc suits the three measures which come with the Orbitor. An exposure frame similar to the Pearles` 8" x 10" but for 5" x 7" instead would need to be made.

An advantage of making 3 1/2" x 5" prints on two seperate 5" x 7" sheets against four 4" x 5" prints on a single 8" x 10" is that the exposure frame need never be moved, the second print of a pair can be made by reversing the paper in the frame.

WHITE BORDERS ON CIBACHROME

Multi-Format exposure frames such as the Pearles produce borderless prints which suit most people. Some however would prefer prints with borders. With positive to positive prints the ordinary masking frames give black borders which few want. The required being white.

Borderless exposure frames can be made to give white borders if used with suitable image masks. These are similar to the masks described by the Pearles for their Multi-Format frame (Newsletter 44) exept that they are made to the format size less on both breadth and length by the width of the required border. When making care must be taken that the slides are square with each other and are straight and smooth. They give the inside outline to the picture and faults are noticeable and cannot be corrected.

In use the mask is put on top of the print just exposed in the frame and pushed into one of the corners so that two adjacent slides butt against the corresponding sides of the exposure frame. On the other two sides there is a gap equal to the required border on those sides of the print.

The slide is now taken out of the enlarger whose light is switched on to continuous working. An exposure more sufficient to burn out all the colour leaving base white only in the unprotected gap, is given. Then without any need to switch off the light the mask is slid over the diagonally opposite corner so that the gap is now on the up to now protected sides of the print. The exposure is repeated and the lamp turned off.

If as in multiple printing from one slide, it is not desired to remove the slide from the enlarger. A suitable spot light at the enlarger can be used instead of the enlarger's lamp.

COMMENTS

As Arthur explains, he has kindly donated the book "Complete Guide To Cibachrome Printing" by Peter Krause & Henry Shull, to the CRC Library. Published by K.P. Books, of Tucson Arazona. U.S.A. This is an excellent book which contains Eleven sections explaining the various steps into Cibachrome printing. From Part one which explains how `Light & Colour` works and mixes to produce the neutral colours spectrum and how it can be used for photographic purposes. Part 2 covers Colour Photography and the additive and subtractive colour reproduction. Part 3 explains how the Cibachrome process came about and how the sensitive layers are formed and even giving details of the differences, advantages & disadvantages of the system. Part 4 gives scematic details of the paper`s density and spectral curves, exposure times and reciprocity failure. Part 5 starts in earnest into P-30 & P-3 Cibachrome processes, explaining solution composition & mixing, and solution life, misuse and substitution and standard replenishing rates. Part 6 assists you in equipping your darkroom with details on using the Enlarger and using colour filters, while Part 7 is all about exposing the print material, which includes a nine-part ring-around guide to exposure steps.

Part 8 explains the use of processing Cibachrome A11 print material and information on choosing a processing method such as processing drum or auto colour processor, or tray processing. Part 9 is on special exposure and processing methods, such as Burning-in, Dodging and using contrast masking and Flashing, including Local Colour Correction and contrast printing. This includes pictorial samples of Common Exposure and Processing errors. Part 10 is about Creative & Experimental Techniques including Sandwich slides, Photographs and using Texture and Overprinting with B&W letterings, plus a section on In-Camera Exposure of Cibachrome. The final chapter is called `Finishing Touches` which includes, Removing fingerprints, Retouching, Hot & Cold Laminating, Mounting by the Heat or Dry methods, Print Edging and framing.

All in all quite an excellent book with dozens of example colour prints to explain the sections. Originally costing around £10, the book will cost around £1.50 in postage (£3 return), but well worth it. If you are interested details of the Hon. Librarian`s address and phone number is on page 16.