Tim Rudman

Tim Rudman

Member, Freestyle Advisory Board of Photographic Professionals


Dr. Tim Rudman is well known as an accomplished photographer, master printer and authority on darkroom techniques as well as a regular writer and lecturer. He has conducted workshops on printing and toning techniques in Britain, Spain, Australia and USA. He is a Fellow of the Royal Society of Arts, The British Professional Photographer's Association and of The Royal Photographic Society in Great Britain, where he sits on the Society's Distinctions Panel for Visual Arts and is the Chairman of its Distinctions Panel for Photographic Printing. Tim is a member of the Arena group and is the immediate past Chairman of The London Salon of Photography. He was awarded an Associateship by the India International Photographic Council, for services to photography, and holds the distinction of Excellence of the Federation International de l'Art Photographique. Tim's work has been widely exhibited in over 25 countries, receiving numerous international awards and is held in several permanent and private collections around the world. Tim was a main feature writer for Photo Art International throughout its existence until its demise this year and has published several hundred articles on photography and printing in Europe, America and Australia.He has published three books. The first, 'The Photographer's Master Printing Course', was an instant best seller with the first print run selling out in just 4 months and has been regularly reprinted. This was followed by 'The Master Photographer's Lith Printing Course', which was widely acclaimed and remains the only book on this beautiful process. His new book 'The Photographer's Toning Book...the definitive guide' has met with much critical acclaim as the most comprehensive book on the subject.


The Importance of the Darkroom In Photographic Education

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This is an unusual question and quite difficult to visualise without seeing the results. I am not clear from your description whether the various filters you use are in front of the camera lens or the enlarger lens. If the former, the results should be on the negative and the enlarging distance should not matter, other than some contrast effects perhaps. I think therefore that they must be in front of the enlarger lens. The diffusion effects produced here would likely alter as the magnification increased and consequently the infectious development could cause blacks to appear in different fashion on the larger prints - I have not tried your technique, but can well believe this could happen as the kicking in of the 2nd development stage is very much influenced by relative exposure ratios. What puzzles me more is that you report that the effects reverse again to 'normal' (using the term very loosely!) at even greater magnifications. I suggest that you try adjusting the lens to filter distance as the lens to paper distance goes up. This should affect the amount of unwanted detail you are getting. The texture might be affected by printing through different contrast filters as you are using MGWT paper. I rarely use contrast filters for my Lith works as they increase the already long exposure times and I can get the effects I want without using them. However, your objectives and techniques are different to mine and it would be worth experimenting with this - although I must stress that this is quite theoretical on my part, not FROM experience. You might also want to experiment with adjusting the developer dilution. Stronger (and fresher) mixtures with perhaps some extra bromide will give results with more graphic effects, more texture, greater split and colder tone. Higher dilutions give warmer colours but also favour more highlight tonal differentiation. If every thing else fails you could scan the 10 x 8 print and make a large acetate negative for contact printing. I wish you good luck with what you are doing. It sounds fascinating!
Dear Frank, Whilst a considerable amount has been written about archival preservation and deterioration of film stock Frank, because of their commercial and archive storage importance, much of it has been to do with motion picture film and microfilm. Not so much that I know of, which directly answers your question. (Which is not to say that it has not been documented of course, only that I am not currently aware of it.) For the short answer, I should say first of all that, from a practical point of view and assuming normal darkroom use, I have never heard of negatives fading from exposure in the enlarger. However, you don't specify whether you are referring to conventional silver negatives or to chromogenic negatives, which as you know are based on colour film technology and contain dyes, they do not contain silver. These two materials are different. Henry Wilhelm's seminal book 'The Permanence and Care of Color Photographs: Traditional and Digital Color Prints, Color Negatives, Slides, and Motion Pictures' examines (amongst other things) the fading of colour film as a result of 'visible light and UV radiation by the image dye molecules, causing them to break down', but this is in relation to the intense exposure involved in motion picture projection. He also states that it is the light rather than heat that causes the dyes to fade (see the second part of your question). These conditions are very different from the exposures given in the darkroom of course, but we do know that colour transparency film fades with repeated projection. I have therefore asked my friends at Ilford/Harman Technology if they are aware of any reports of fading of their chromogenic Black and White film 'XP2 Super', as a result of enlarger exposures. The short answer was no, but the question has been passed to their technical department and if there is anything further to report from them, I will let you know. They were also unaware of this problem occurring with silver based negatives exposed in the darkroom, and again I will let you know if there is any further news from their technical department on this. During the 1980's The Image Permanence Institute in Rochester, NY, conducted work on silver based microfilm and ways in which its permanence might be improved. In their paper 'Stability of Black-and-White Photographic Images, with Special Reference to Microfilm' authors Reilly, Nishimura, Cupriks, and Adelstein described the mechanisms of fading with silver, either as improper processing or oxidising chemicals, the driving forces being moisture, air and pollutants (notably gases) - not light alone - and they examined the protective benefits of selenium, gold and sulfiding. Their paper makes interesting reading, for although it doesn't directly answer your question, it suggests the mechanisms for silver fading lie in other areas to those you are asking about, but more importantly, it underlines the importance of careful processing and protection - which I am sure outweigh any theoretical risk from enlarging exposures. I will let you know if I find any further information on your question.
Hello Mark,
There are quite a few references for making your own developers. As you suggest, The Darkroom Cookbook is a good starting point. It explains the basics and gives a range of formulae for different types of developer and what they do. It does also go into the function of the different components.
Some websites that you might also find useful (although probably going over more or less the same ground) are:

However, I sense that you want to avoid using existing formulae in favour of starting from scratch with your own. The existing formulae do have the advantage that they have been used for many years and there are people around on the internet discussion groups who use them and are happy to discuss their experiences. This can be a very good source. I would recommend Pure Silver (via http://www.freelists.org/ ) - or the now much bigger and more active APUG site. This is an internet community of 'analogue' photographers with over 16,000 members and they have discussion forums for any analogue interest - including chemistry, making developers etc. They are a very friendly and helpful group. As always, the members range from the expert to the not so expert but you would find them a useful resource I am sure. They are at http://www.apug.org

Kind regards,
Hello Shawna Firstly, perhaps I can say something about what often makes some papers unsuitable for Lith printing, because knowing this can save a lot of time and experimentation. Resin coated (RC) papers typically develop very fast - almost instantly in some cases. This is partly because they may contain incorporated developer agents or development accelerators mixed into the emulsion. Such papers will not usually be suitable for lith printing as these agents take over the development and interfere with the infectious development process, on which lith printing depends. Fibre based papers do not normally contain these agents and as a group are rather more likely to be suitable for lith printing than RC papers. However, there are some RC papers that share the same emulsion as their FB counterpart - i.e. the paper comes in two versions, FB and RC which are otherwise virtually the same. In these cases they usually lith print (or not) as well as the FB version. Fomatone MG Classic (which is FB) and Fomatone MG (which is RC) are examples, and both lith print to give the same effect and colours. If in doubt about whether an RC paper contains these products take a small piece of the paper in question into the daylight and add a few drops of Lith B developer. If a black quickly appears, proceed no further - that particular paper is not going to lith print successfully. Now, what makes a paper lith printable? For success in lith printing the emulsion must be capable of "filamental crystal growth" when over-exposed. As a general (but not absolute) rule, papers with small or fine grain emulsions are more likely to do this and tend to lith print best. I.e. most good lith papers are warm-tone papers. However there are exceptions and there are other factors that facilitate lith printing: For example, Kentmere, who manufacture some of the most 'lithable' papers, tell me that removing the supercoat seems to allow this to happen with their Bromide emulsion, and bromide emulsions are of course typically cold in tone and large grained. Other constituents also promote lith printing. Cadmium is perhaps one of the better known and papers that contain this generally excel for lith work. For environmental reasons, cadmium is now restricted in the manufacturing process of photographic papers and consequently some of our favourite lith papers are now cadmium free and this significantly alters their response in lith developer and in toners, notably selenium. Whilst they may still lith print, they have a different look. Adding pigment particles to the emulsion also seems to act as a partial catalyst in lith printing in some cases. For example Kentmere's Fineprint Warmtone liths well - but the same emulsion as Fineprint, without the pigment, does not lith print. So you see the process is complex and as you can't tell what pigments have been added to a paper that you buy, or whether they were added to the emulsion or to the paper base before coating, it helps to have a master list for reference. Such lists can be found in my lith printing books 'The Master Photographer's Lith printing Course' and the new 'The World of Lith Printing', but we live in a changing world and materials for silver gelatin printing alter all too frequently.
Dear Mark, The answer to this question is not simple, as so many variables affect the outcome with FSA, sometimes to a large degree. Using bleaches based on the 3 different halides can produce very different results with the same paper in the toner. I did write up a chapter on this in my toning book, which you might find interesting. However, this is only the tip of the iceberg, as these results can be modified considerably by partial bleaching or partial toning, or by both. You have chosen for your example a toner that is capable of an unusual range of effects and also (unusually) substantial increases in density, thus expanding the options with partial toning, as complete redevelopment may be unnecessary for adequate density recovery and this can affect the colours. Throwing into the equation a mix of different halide bleaches sequentially on the same print must have some other effects and I imagine is quite possible to do, but I wouldn't care to predict what these might be - and in any case, the results are likely to vary with different papers as well as bleach times, solution strengths, and whether or not there is an R in the month! In short, there could be unpredictable results of spectacular interest or thoroughly underwhelming appeal! The only way is to experiment in true pioneering spirit and find out for yourself, keeping careful notes and changing only one variable at a time - otherwise you can be sure that the one experiment that you truly like above all others will be the one where you can't remember what you did! I spent more hundreds of hours playing with toners than I care to recall, but you have unerringly alighted on on that I didn't do, so have a go and let us know your results. With kind regards,