Hi, I've been processing films in my improvised darkroom at home for a while. The results I get with color negative and slides are fairly good. Well developed, fine grain, good saturation, etc. However, lately I've noticed an increase in grain in my processed b&w films. I've been concentrating in Ilford emulsions, mainly Delta100, PanF 50 and FP4 100. The last two films, according to Ilford, produce the finest grain with Perceptol when used at full strength and that's what I'm using. I'm keeping the temperature at 20C by adjusting the tap water. I agitate by inverting the small tank 10 times every minute (1 inversion per second) and am processing at recomended times. Fixing is done with Ilford Universal Fixer or Kodak Rapid fixer. No stop-bath is used, just plain water filling and draining the tank about 5 times. At first I thought it was my enlarger, then I got a slide scanner (Minolta Dimage Dual II) and the scanned negs look grainy too. I've already tried TMAX developer but there's no noticeable change. I might be doing something wrong since with slides and color negs I have no problem. With those I use Agfa kits for C41 and E6. Any thoughts? Could that be my tap water? Should I try warmer development instead of 20C? Herbet.

-- Herbet Camerino (herbetb@yahoo.com), February 05, 2001

Answers

Response to Grainny film - What am I doing wrong?

Are you practising to become a cocktail waiter by any chance, Herbet? Because you're giving the film Far Too Much Agitation! You're probably overdeveloping the film as a result.
Two inversions per minute are more than enough.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 05, 2001.

There's no such thing as too much agitation _providing development time is appropriate_.

To translate, if you have a satisfactory development time based on agitation of five seconds every 30 seconds or 10 seconds every minute, if you then change to continuous agitation you'll need to reduce the time by around ten percent. Otherwise you'll have negs that are overdeveloped and show excessive contrast and graininess.

And you need to take a look at development time. Generally, the negs should print on grade 2 to grade 3 paper or if you're using a dichro enlarger, 25M to 40M filtration. When using small format it's often good practice to develop it a little less with the target of printing most negs on grade 3 paper; this decreased development reduces graininess and makes tonal rendition a little better.

So consider what grade paper you're printing on or dichro settings. If you're printing most negs on grade 2 to grade 1, back off development around ten percent or reduce the agitation to two or three inversions every 30 seconds.

You mentioned Perceptol. Usually a fine-grain developer such as Perceptol or Microdol-X used straight requires a lower film-speed setting to be used, or iow, the effective speed drops and the film needs more exposure than its ISO rating would indicate. If you're not doing that you could be underexposing the film; if you then overdevelop or print on higher-contrast paper to compensate that'll also increase graininess.

The C-41 and E-6 processes are designed for continuous agitation and development-time recommendations are based on that, while b&w development is usually assumed to be with intermittent (5 sec/30 sec) agitation and development recommendations are based on it.

-- John Hicks (jbh@magicnet.net), February 05, 2001.

I have to second the notion for decreased agitation, more along the lines of 4 inversions per 10 seconds. According to The Film Developing Cookbook, less frantic agitation can also improve tonal scale.

-- Brian Hinther (BrianH@sd314.k12.id.us), February 06, 2001.

> According to The Film Developing Cookbook, less frantic agitation can also improve tonal scale.

That makes no sense; too bad neither of those guys participate in these forums so they can be asked exactly what they meant to say.

Modern films routinely provide a very straight curve shape (if that's what's desired) from the speed point all the way out to five or six stops more range than anyone could ever hope to print on silver paper whether intermittent or constant agitation is given.

If that's not what's desired, modification of the curve shape can often be achieved by using different developers and this can be done with constant agitation as well as with intermittent agitation.

See _Controls in Black and White Photography_ by Dr. Richard J. Henry for more than you ever wanted to know about the effects...or lack of effects...of different methods of agitation.

-- John Hicks (jbh@magicnet.net), February 06, 2001.

I tend to agree with John concerning agitation. I think that the use of Jobo tanks kind of proves that continuous agitation doesn't really affect grain. I might look at a different thing here. Herbert, you state that you are pretty careful about keeping your developer at one temperature. But you don't say much about what temperature your other solutions are at. I have experiences grain migration in the past when I have inadvertently used varying temperatures for all of the solutoins required for development of films. In addition, it is well known that the longer a film is wet the more grain migrates (clumps) to make grain appear larger. I would try this. Keep all of your solutions the same temperature. Use a stop bath for 30 seconds instead of the many rinses. Use a hardening fixer. and keep the wash water at the same temperature as the rest of your solutions. Let us all know the results. kevin

-- kevin kolosky (kjkolosky@kjkolosky.com), February 06, 2001.

"In addition, it is well known that the longer a film is wet the more grain migrates (clumps) to make grain appear larger." - What?. This is sheer nonsense. Some of the finest grain developers also have the longest development times. I think this disproves that 'well-known' theory, but by all means test it.
Take a fine grain negative and print it, then put it back in the wash for, say 4 hours, dry it, and print it again. If the grain is increased, I'll gladly donate a tenner to the charity of your choice.

Gross temperature differences between processing baths can give rise to 'reticulation'; a micro cracking or wrinkling of the gelatine. It can look like severe grain, but isn't grain at all.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 07, 2001.

It looks like my tenner is safe, unless Kodak have got it all wrong.
Here's what they say in one of their technical publications on grain and granularity.

"Development usually does not change the position of a grain,.....", and again in the caption to Fig. 22. - "Contrary to widely held opinion, there is little migration or physical joining of individual grains."
I hope this lays one 'well known' myth to rest, since I could find absolutely no contrary reference to grain migration in photographic film at all.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 07, 2001.

Hi, I just wanted to clarify that all the process is being done in 20C. The water bath between the developer and fixer is also at 20C and it doesn't last longer than 1.5min I did try using Kodak Rapid Fixer which is contains hardener but no apparent difference. The negs do not look overdeveloped. The only slight difference in temperature is in the final bath with photoflo mixed with filtered water around 23C. I don't think that small variation would cause reticulation. I'm seriously considering using the TmaxCN from Kodak that can be processed in C41. I saw enlargements from it with almost no apparent grain. Herbet.

-- Herbet (herbetb@yahoo.com), February 07, 2001.

Try this:

For one test, mix _all_ solutions with distilled water and use distilled water for the wash. To use it for the wash, fill and dump the tank at least eight times. Be sure all temperatures are as close as you can get them.

Compare negs from that test to your grainy ones.

The reason I mention this is that many years ago I had a problem in which negs suddenly became _really_ grainy; the only difference was a change in water supply.

I went through mixing solutions with distilled water only to have the same results but I didn't change the wash water. Ed Meyers referred me to a chemist at Agfa who said that the wash water was the likely cause, especially since it was the only thing left.

I installed a Culligan ion-exchange water softener and the graininess problem was solved; the negs were back to normal.

So...assuming you haven't moved to a new water supply, perhaps what's happening is that there's some seasonal change in the hardness of your tap water or what's being put into it.

-- John Hicks (jbh@magicnet.net), February 07, 2001.

John Hicks wrote: >So...assuming you haven't moved to a new water supply, perhaps >what's happening is that there's some seasonal change in the >hardness of your >tap water or what's being put into it.

That's very likely. Since the incident of e-coli contamined water in Wakerton the City of Toronto has been increasing the volume of chemicals (mainly clorine) in our tap water. Would the water filtered through one of those Brita carbon activated filters work fine? Herbet.

-- herbet (Herbetb@yahoo.com), February 07, 2001.

Greetings,

I too agree with the water being the source of your problem. As a JOBO user (read continuous agitation) I can disprove the larger grain theory caused by increased agitation. The effect of constant agitation on grain size may be measurable from a scientific standpoint, but not aparent from a practical one.

I would not recommend the carbon activated filters. First, their level of effectiveness is not constant over their life. They can be highly effective for the first few gallons, but will change dramatically there after. Secondly, the carbon may not filter what's in the water, or may interact with the chemistry. I would stick with distilled water for the developer.

Regards,

-- Pete Caluori (pcaluori@hotmail.com), February 07, 2001.

I believe the Film Developing Cookbook comment about reduced agitation means moreso:

1. compensation can take place with reduced agitation and is inhibited by excessive agitation.

2. edge effects are also inhitibited by agitation.

-- Charlie Strack (charlie_strack@sti.com), February 07, 2001.

> 1. compensation can take place with reduced agitation and is inhibited by excessive agitation. > 2. edge effects are also inhitibited by agitation.

I agree with those two comments.

Actually I don't see any way any significant level of "real" compensating development could be achieved with continuous agitation. While it's possible to generally duplicate the curve shape, that's not the same although in practice it may not make any difference.

I think it's probably possible to get more edge/adjacency effects when using continuous agitation than expected although I believe those effects would surely be inhibited. It's my understanding that most edge/adjacency effects happen _within_ the emulsion via diffusion so wouldn't be entirely absent.

Henry had quite a bit to say about acutance and edge effects but I've forgotten exactly what he found regarding freqency of agitation in that respect.

-- John Hicks (jbh@magicnet.net), February 07, 2001.

> That's very likely. Since the incident of e-coli contamined water

OK, that's something to investigate. Note that for the test it's important to use distilled water for _everything_ including the wash.

I realise it's probably ridiculously impractical to continually use distilled water if you find that's the cause of the problem; I have no idea what to do about that other than ask water-quality specialists, preferably people who aren't trying to sell you their filtration system.

Can you think of anything else you've changed. Different HCA perhaps?

-- John Hicks (jbh@magicnet.net), February 07, 2001.

Pete I was just reporting my experience. I don't know what Kodak says, but I have had grain problems when not keeping my solutions close to the same temperature and those grain problems were cleared up when I tightened up the temp differences. Moreover, I was speaking about wet time BEFORE fixing the film, and not after fixing the film. Yes, fine grain developers have much longer developing times that other developers, but I am talking about total immmersion in liquid prior to fixing, such as pre wet time, stop bath time, and also fixing time. Let us all not forget that "grain" is actually the space between silver particles on the negative and not the silver particles themselves as the silver particles block the light from the print, whereas the clear spaces between the particles let light through which looks to us like "grain". The larger the space, the larger the apparent grain. This is just my theory, but it seems to me that if there was some silver halide there and it is not there now, it must have migrated somewhere! And of course, the other thing may be the type of developer used, as has been suggested, different chemicals have different effects on the silver halide crystals concerning their shape and their edges. I certainly don't pretend to be a photographic chemist, but I do know grain when I see it and I know that when I was very careful about temperatures mine went away. It could have been something else, and if it was I wish I knew what it was. Kevin

-- (kjkolosky@kjkolosky.com), February 08, 2001.

A charcoal filter WILL help remove some things, including chlorine from the water. They do vary in effectiveness over the life of the filter. It depends on the amount of chemicals in the water and the amount of water you run through the filter.

Charcoal will not cause any trouble with your chemistry. Every charcoal filter has a final particulate filter to keep the charcoal from getting out.

What I did (very hard well water) was to buy a table top distiller (Sears in the US). This distills 1 gallon of water in about 6 hours. I have a 10 gallon storage tank and use distilled water for everything except washing. Tests have shown that distilled or very soft (low mineral content) water increases wash times tremendously.

However, I agree with John that as a test you should process with distilled water thoughout the process and see what happens. If things go back to normal, try distilled water for everything except the wash. If this is fine, you can either test more or use distilled water for all chemical steps. If you continue testing, the developer step is most likely to be the one sensitive to water quality.

-- Terry Carraway (TCarraway@compuserve.com), February 09, 2001.

I use ilford pan f 50 all the time and delta 100. I use d-76 and have never noticed grain in prints until after 11x17. If you go bigger than 11x17 you notice small grain in the 50 and a little larger in the 100. Use tmax 100 and you will see what grainy is.

Using 35mm will give you grain in large prints now way around it.

If you don't like the grain and want bigger prints go medium format.

-- alffonso (awright@anera.org), April 16, 2001.