Thornton & Rodinal

[anyhuus]

I am not very familiar with Rodinal (tried it occasionally on a handful different films, but no systematical testing or anything like that), but I'm curious and would like to understand the developer a bit more.

As far as I have gathered, it is considered to be a high accutance developer, much like Beutler's or other dev.s with low suphite contents. It made me wonder if the late Barry Thornton ever used Rodinal - being so focused (!) as he was on accutance and compensation for that matter. He made his own variant of Stöeckler two-bath with accutance in mind, and later devised his own dev. (DiXactol) - still with accutance in mind. It would seem logical that he tried Rodinal, but I can not find any reference to that.

Are there any known sources on Thornton's view on Rodinal?

Maybe a peculiar question, but it's only an approach for me to gather information to familiarize myself with Rodinal

 

[Dan Henderson]

In Chapter 7 of his book, "Edge of Darkness," Thornton reviews common developers while describing his quest for his holy grail of a high acutance developer. He does mention Rodinol, which implies that he used Rodinol enough to at least observe its effects.

 

[Peter Black]

In example 5 (Lough, County Kerry) in his book Elements, he speaks of developing T-Max 100 in Rodinal "to try to give this fine grain film improved apparent sharpness". He concluded that his chosen time of 5 minutes at 1:25 was too much, and that Agfa's recommended 1:50 would have given extra compensation and kept the sky more transparent on the negative.

There may be other examples, but I haven't time to look just now.

 

[gainer]

There is only so much artificial acutance one can achieve without loss of resolution. The edge effects on narrow lines and fine detail can run together in the middle. I concluded once in an article in Photo Techniques that a modicum of sodium ascorbate added to Rodinal improved it somewhat.

The best bet for acutance IMO is to make the microdensitometer trace of a knife edge look like the cliffs of Dover, a true step function. Your eye will then see all the acutance it needs. Test it visually by photographing a resolution test pattern and comparing line widths of the original with those of the copy.

 

[gainer]

P.S.
If you improve Rodinal too much, you will ruin it.

 

[Keith Tapscott.]

Are there any known sources on Thornton's view on Rodinal?

My own correspondence with Barry Thornton, was that he favoured Ilford Perceptol used well diluted over Agfa Rodinal. At the time, I bought some Di-Xactol from him and he sent this to me and included a free sample of his Exactol (I think that`s what it was called) developer. I haven`t used any staining developers since though.

 

[john_s]

From memory, having read Barry Thornton's two books some time ago, he was well aware of the need for grain to promote the appearance of sharpness, but found that Rodinal produced grain that he found distracting in uniform skies. The example he gave looked pretty bloody good to me, but that's why he stopped using it. (I think it was T-Max100 in 120 size, but I'm not completely sure- I could look it up later if anyone was interested)

Gainer's article in Photo Techniques had some very convincing examples: improved but still with character. If I were looking for yet another developer to try, I would definitely give the Gainer-Rodinal a go.

 

[gainer]

From memory, having read Barry Thornton's two books some time ago, he was well aware of the need for grain to promote the appearance of sharpness, but found that Rodinal produced grain that he found distracting in uniform skies. The example he gave looked pretty bloody good to me, but that's why he stopped using it. (I think it was T-Max100 in 120 size, but I'm not completely sure- I could look it up later if anyone was interested)

Gainer's article in Photo Techniques had some very convincing examples: improved but still with character. If I were looking for yet another developer to try, I would definitely give the Gainer-Rodinal a go.

Here is a slightly different perversion of Rodinal. Use the ascorbic acid-borax solution (35 grams of ascorbic acid and 100 grams of borax to make a gallon)described in the article about Metol and ascorbic acid to dilute Rodinal stock. One part of Rodinal stock + 49 parts of the diluent make an 8 minute developer at 70 F. It can be reused for several rolls. 250 ml will develop one roll or 1 8x10 equivalent area. You can't see all the good qualities here, but the gradations should show fairly well.

 

[john_s]

Gadget! With your scientific background why are you listing grams/gallon? What is a gallon, anyway? Here at the British end of the Earth it used to be 4.546_Litre, but where you (probably) are it is, I think, 3.785_Litre. Can you confirm that you actually mean 9.2gram of ascorbic acid plus 26.4gram of borax in a Litre of water?

If someone wanted to try one of these two Rodinal improvements, which would you recommend? (The two I mean are the ascorbic acid + borax, or the sodium ascorbate).

 

[gainer]

I am convinced that the proportions of stuff in the diluent are not that critical. The borax is a buffer that will have the same pH whether you dissolve 90 or 100 grams in a gallon or in 4 liters. The difference would be seen if you created enough HBr through development to change the pH. The ascorbic acid is, at least in my view, acting as an antioxidant with the ability to regenerated the Metol or Phenidone or p-aminophenol or Amidol or any one I forgot, and the only effect its concentration will have is on the time constant of regeneration, which will only be seen when the molar concentration goes below 0.05 moles/liter, according to research by Mees & James. So it is in fact my scientific experience that leads me to think that whether you mix it in a gallon container or a 4 liter container, you ain't gonna see a difference in the results. There will be more difference in time of development due to individual preference for contrast, etc., than to concentration.

While we're on the subject, I would recommend that when doing the drastic dilution for long term stand development, you dilute more by adding less Rodinal to the ascorbic acid-borax solution.

 

[gainer]

I forgot to answer your second question. I think it is easier to keep on hand a supply of the ascorbic acid-borax solution. You can use it or not as the spirit moves when you have time for play. When I was learning to play the oboe, I read that a famous oboist said "If you want to learn to play the oboe, you must play with the oboe." The word "serendipity" comes to mind.

 

[3Dfan]

Does the ascorbic acid-borax solution increase/decrease the film speed versus just plain rodinal?

 

[gainer]

I usually bracket my exposures +and- 1 stop when I am doing pictorial tests. I don't see any difference except density between box speed and 1 stop over. 1 stop under begins to lose shadow contrast in both plain and perverted Rodinal. This change in curve shape makes it more difficult to get a good print unless that is what you seek. More development will make ends meet so to speak, but the inbetween may not suit. These same comments apply to most developers I have tried.



Of course, a lot depends on how you use film speed to calculate exposure from your meter readings.

 

[Bruce Osgood]

.......
in both plain and perverted Rodinal. .....

I've been using Gainers' Rodinal variant and referring to it a G-Rodinal. But I think I much prefer Perverted Rodinal better.

 

[gainer]

So do I.