LITH FILM and SOME OF IT`S APPLICATIONS

By  the late Dr. G. A. W. Neill

As suggested by John Batty (Area 9)

I received, both before and after Dr. Neill`s death, lots of his equipment "and a few of his photographic notes. The on here I thought may be of interest to members:­ 

Slides make a better impression when they are presented with satisfactory Titles and Credits. It is necessary sometimes to include diagrams and maps in presentations. For those purposes LITH FILM is extremely useful. Widely used commercially as sheet film in the printing trade, it is available in the 35mm format. "KODA LITH Ortho film 255. Type 3 " is probably the most readily obtainable. (Jessop of Leicester - £15.20 for 100ft). This film is consistent. Its ISO rating is ISO12. It can b e handled under a red safelight and it stores satisfactorly for a number of years. If high contrast is  required it should be developed in a high contrast developer, such as Kodak D-8. Quite satisfactory results can however be obtained with a general purpose print developer such as D163 or ID62. It comes with very full data enclosed in the container can. 

KODAK DEVELOPER D8:  

For those who would wish to use it, the formulae is:-

Stock Solution:

                  Sodium sulphite (anhydrous)     90.0gms. 
                  Hydroquinone                           45.5 gms. 
                  Caustic soda                              37.5 gms. 
                  Potassium bromide                    30.0 gms. 
                  Water to 1000.0 mls. 

For use take 2 parts of stock solution to 1 part of water. Develop for 2 minutes at 20C. Developer keeps for several weeks bottled. It retains its use for several hours in an open dish. 

Without loss of density the caustic soda may be reduced to  28.0 gms, in which case the stock solution will keep longer still - (perhaps 3 months at least). 

LITH film is obtainable from other sources which supply it in smaller quantities and at lower cost. Experience has shown that these are very inconsistent. ISO can be as low as ISO 3, and the contrast rather less than Kodaliths. In view of its good keeping qualities and the many possible applications, 100 ft of Kodalith is not a bad bargain.

The usual practice in making Lith titles is to load a cassette with Lith film and photograph title or diagrams in the usual way. For this the ISO 12 of Kodalith is an advantage over the slower material. Develop - stop bath and fix the resulting negative. A positive title transparency can then be obtained by contact printing. A useful printing frame for this purpose can be made by obtaining from a glass dealer several strips of plate glass the exact width of 35mm film and approximately the length of 6 frames. Two pieces of 3/4" angle aluminium a little shorter than the glas and screwed down to a suitable base board in such a way that a glass strip just fits between them. 

The negative strip and a matching strip of un-exposed film are placed under the glass, emulsion side to emulsion side. Then the contrivance is placed under the enlarger and exposed. The exposure is estimated in the same way as for a black and white print. Reversal development of Lith film is possible and can be quite satisfactory. The process is generally similar to Colour Reversal but differs in several important details - either white light or chemical reversal may be employed.

Titles and Credits maybe made with Lith film, either from the original negatives or from positives. Negative titles backed by coloured foils are particularly suitable for superimposing on colour transparencies with a dissolve unit in an AV sequence. Positive transparencies are used in making "sandwich" titles and it is here that the very high contrast of Kodalith is a great asset.

Lith film can be used for making positive Black and White transparencies from ordinary Black and White negatives, either originals or made with a Slide Copier from Colour Transparencies. It has the advantage that contact printing under a safe light and developed by inspection is possible - somewhat easier than using a slide copier or bellows. Contrast can be controlled by exposure and choice of developer.

Lith film has also many possibilities in Creative Photography - Positive and Negative Lith slides can be projected on a single screen with 2 projectors, through coloured filters and slightly out of register, the resulting screen picture can be photographed asa colour transparency to produce an interesting effect.

The Sabbatier effect can be obtained by experimentally exposing Lith film to white light during development, this provides Creative opportunities.

Apart from all this, Lith film offers infinite possibilities for making Masks for slides. here again a slide copier can be useful. Should however soft edge masks be desired,it is as well to make the original negative on a low contrast ordinary black and white film such as Pan X or FP4. It is also prudent to have on hand some "Photo Opaque" to deal  with "Pin holes", though these are much less frequent with Kodalith than with some other offerings from the photographic trade.

Finally for those who want good quality titles without investing in  100 ft of Kodalith, High Contrast titles can be made by developing Pan X or FP4 in the Kodak KD8 developer.

The disadvantages are:

(1) Such films must be handled in absolute darkness and this tends to make contact printing difficult - so the slide copier must be used again.

(2) The film base of these films have a Bluish-Grey coloration which detracts from the high contrast."

I have recently bought 100 feet of the said film - cost £21 to £22.

          John Batty.