grainy FP4 in ID-11 1:1

[Zsolt Kis]

Hi,

I develop my 4x5" Ilford FP4 film in ID-11 diluted to 1:1 at 20 Centigrade. When I look at the result on the light table with a 4x loupe (JOBO), I find the grain quite visible. I use JOBO CPE2 machine to develope the films and follow (at list I believe so) the instructions. What could be the reason ?

[Andrew_4548]

Zsolt,

This might be a bit basic but are you reducing the times for rotary processing? AFAIR Ilford suggest -15% as a starting point.

I'm using the same film / dev combo as you with a 3005 drum and don't have any problem with my architectural stuff where I want fine detail...

[Kevin M Bourque]

Is the grain visible in a normal sized print?

[Andre Noble]

I think there's a lot of other things you should be concerned about before you get to looking at grain, such as how's the negative's density and contrast?

The answer to that will provide you clues as to the problem with the grain.

[Zsolt Kis]

Andrew,

I reduce the developement time by 15%, and I have just realised, that probably it is not enough, because my negatives are too dense. So I should probably further reduce the development time. In fact, I also shoot architecture. May it be the problem, that I overdevelope my negatives ?

Kevin,

I do not enlarge them, I want to scan. I use an EPSON 3200 scanner and it turned out that the dynamic range of the scanner is not wide enough for my negas., although it is commonly said on this forum that it is.

[Zsolt Kis]

André,

You are probably quite right, my negatives are too dense. Can it be the reason of increased graininess ?

[rich silha]

the longer the processing time the more grain.

[Andrew_4548]

How about the rotational speed of the Jobo? I think on mine I have it set vers slow or just about moving - even the "F" (film?) setting is quick. Wouldn't extra "agitation" bump up the contrast / grain etc?

[Leonard Evens]

If the densities in your negatives are too high for the Epson 3200 scanner, it would seem that they are way overdeveloped or way overexposed or both. I scan b/w with an Epson 3200. I have developed Ilford HP5 and Delta 100 in D76 1:1, which is the same as ID-11, using a rotary drum. I sometimes overdevelop a bit, compared to what I would do for enlarging, in order to expand the dynamic range a bit, but I've neve seen a density higher than about 2.4. Usually the highest density is about 2.1-2.2, and if I were to use normal development for enlarging it would probably be about 1.8. The scanner supposedly can handle up to 3.4, and from my experience with transparency film, that seems accurate to me.

One question I would have is how you are estimating the densities. With typical scanning software, the RGB values you get should not be confused with densities. The scanning software will attempt to fit the range it finds in the negative within the values 0..255, and that can depend on the particular negative. Also, it may go about it differently for negative film and for transparencies. Vuescan, which I use, claims to be able to tell you the actual densities. You hold Ctrl while moving the cursor around in the image to read densities. That is what I use to estimate densities. I haven't checked the values against an actual densitometer, but the values look like what I would expect from my long experience with b/w negatives in the darkroom. Sometimes, they seem a bit higher than I would expect (by about .2-.4) but the density differences between highest and lowest seem right in any case.

If you are finding that the highest important values are 255 whatever you do, it could simply be a matter of adjusting you development, but there may also be ways to get your scanner to see higher densities. I assume you have set the black and white clipping points to the most extreme levels, so you aren't clipping anything. One thing you could try is telling the software it is scanning transparency film and then inverting the image in a photoeditor. For color negatives that would be a mistake, but for b/w, it shouldn't make any difference. I think there are other ways to do it with Vuescan with the b/w negative setting, but I haven't explored that yet since it doesn't seem necessary for me with my present techniques.

As to grain, are you sure you are seeing actual grain? The scanner is not really capable of resolving grain in these emulsions, but there can be a certain amount of grain aliasing in which the grain spatial frequencies are reflected downward about the so-called Nyquist limit, which is half the scanning frequency.

[mark blackman]

I suggest you check all your timings against Ilfords recommendations (http://www.ilford.com/html/us_english/pdf/FP4Plus.pdf), but from what you've said I can't see how you could have introduced viewable grain (at 4x magnification) without extreme pushing?

do you consistantly get these results - with different batches of ID-11?

[Zsolt Kis]

Thank you all for the responses! As you have already found out probaly, I am new in this bisnis, so I am very grateful for all comments and suggestions.

Andrew,

I use the quickest rotation speed, which is about 70 rotations per minute. This was recommended somwhere, either on the web page of JOBO or in the documentation. I have already realized (because of the bad scanning results), that my negatives are far too dense, the contrast is too large. Since it is not recommended to have less than 5 minutes developement time in a rotary processor, I will try the slower speed, thank you for the idea. By the way, for intermittent agitation the recommended developement time for FP4+ in ID-11 1:1 is 11 minutes at 20 Centigrades. It is also recommended, that in rotary processors, it should be reduced by 15%, hence my actual developement time is 9 min 20 sec. Of course, I can try to reduce the developement time even further, no problem, say by 30% from the basis 11 min, that means 7 min 40 sec.

Leonard,

That is the first time in my life that I scan a film. In fact, this is not my own system, I do it at a university media lab. The scanner is run by Silverfast AI. I have seen a densitometer tool, but I couldn't interpret the numbers becouse the software is in German and my German knowledge is quite limited. But you gave me a good idea: I bought a projection step wedge (Stouffer Graphic Arts) several months ago, which is calibrated. I couldn't use it up to now, because it is impossible to insert the projection step wedge and an other negative into my film holders. My idea was to use it for just calibrating the exposure time (i.e. estimate the film sensitivity) and developement time. But I can insert it to the scanner, and scan it, and I can also test in this way the dynamic range of the scanner, and the readings from the patches can be used to calibrate the densitometer provided by the scanning sofware. I think that should give me a good estimate at list for the densities of my negatives. I have already played a little bit with the Silverfast software and looked what will happen if I set an other sort of negative type before scanning. It essentiall moves to minimal-highest density range in the 0 - 255 interval, but I can always set it by hand. I tried, but I couldn't get significantly better result. Well, it is not a tragedy that my first trials are not so successful, I am still learning.

Mark,

I have read that document that you suggested. The result is not completely consistent, as I get more experienced with timing, using the machine, it seems to get more and more consistent. The grain is much less apparent in less dense negatives than the denser ones.