PDA

View Full Version : Uneven Developement with Diafine - how to test properly?



zechi
21-Jan-2014, 15:41
Hi all,

I'm very new to self developing my 9x12cm black and white negatives (Fomapan 100) and am having trouble with uneven developement. I use Diafine, and a Paterson tank with the taco method, but I also got uneven developement when using trays.

I tried different agitation schemes from the box instructions to the method of "eye of wally" described here

eye of wally's method (http://www.flickr.com/groups/diafine/discuss/72157624165181643/)

.. always uneven development. It seems to me that the harder I agitate the better the negatives get - I ended up inverting for 30 seconds in A and B and after that 5 times every 30 seconds - almost continous agitation but still no even developement. My temps are fine and I used distilled water to mix the chemicals - I also use distilled water for the final rinse.

What would be the best method for testing or for working out a proper agitation scheme? Should I take some test shots of say, an evenly lit wall or is it possible to just take out a sheet of the film holder, expose it to daylight and develope the sheet? It should come out evenly dark shouldn't it? I find it hard to judge the developement of regular pictures sometimes, so I wanted to test in a more controlled manner.

Thanks in advance for your answers & all the best,

Christoph

Mark Woods
21-Jan-2014, 15:59
An evenly lit surface at about 18% will show off any problems you may have regarding development.

Ken Lee
21-Jan-2014, 16:10
You may find that development in a continuously moving motorized tank (at sufficient speed) eliminates the problem.

Nathan Potter
21-Jan-2014, 17:24
I'll second Kens' comment. I use a small motorized tank with just one sheet of 4X5 film with continuous agitation, then toss the developer after each sheet. Don't seem to have any unevenness problems with Diafine unless I've had too much wine and goof. Just used a 2 year old part A and part B solution. Hit the density scale perfectly (well < 0.05 error, at least) and no unevenness.

But I also use tank immersion development with multiple films and with old Kodak SS film hangers and continuous but gentle swinging agitation with no unevenness. I'm mostly calibrated for 3 min. A plus 3 min. B development times at 75 F.

Nate Potter, Austin TX.

Leigh
21-Jan-2014, 20:20
Hi Christoph, and welcome aboard.

You're WAY over-agitating. The instructions say:
"...agitate VERY GENTLY for the first 5 seconds, and for 5 seconds at 1 minute intervals."

Follow the instructions on the box. I don't know who authored the instructions you're using, but I guarantee it was not the manufacturer, so they're useless.

Diafine is a compensating developer. All compensating developers need to sit undisturbed for most of the time so they can work as designed.

Diafine is the most forgiving developer on the planet.
I've used it without any problem for over 50 years.

A couple of points:
NO pre-soak of any kind. Pour Solution A into a dry tank with dry film.
Leave each solution in for five minutes.
Processing temperature should be around 70F, but it does not matter much, and time does not change.

- Leigh

BetterSense
21-Jan-2014, 20:28
With 35mm I found it important to follow the instructions. I agitate very gently maybe 1 or 2 agitations at the start, and again at 30 seconds. I don't agitate again after that because, well, it develops out fully in 3 minutes and mostly in 1-2 minutes anyway. If I agitated less than that I got marks from the sprocket holes; more and I got inconsistent huge grain.

I never used Diafine with sheet film.

Leigh
21-Jan-2014, 20:38
I should add that I use Diafine with all film sizes including 35mm, 120, 4x5, and 8x10.

- Leigh

frotog
22-Jan-2014, 10:29
Your uneven development could very well be due to the long pour times when introducing the b solution. Try turning off the lights, open your Patterson tank and pour the b solution in directly, mindful of limiting the amount of time that transpires before your first agitation in solution b.

zechi
22-Jan-2014, 16:34
Thanks for your quick answers!! Maybe I really did over - agitate ... I'll take some test shots tomorrow and try again with the box recommendations. Could the taco method I use also be a problem in combination with diafine?

As for a motorized tank - would something like a Paterson orbital work?

Also, thanks for the tip with minimizing the pouring time I'll give that a shot too!

thank you for your help,
Christoph

zechi
28-Jan-2014, 12:23
ok so, I finally found the time to take a test shot and develope the negative .. the result is very bad - I tried the box suggestions and agitated gently every minute for five seconds. I inverted the tank gently and tapped it on the counter after every agitation cycle. I did not presoak this time and rinsed the negative after B - I fixed for 5 minutes with constant agitation. I attached a quick scan of the negative. Sorry for the dust but at the moment thats my smallest problem ;-) ..The wall was illuminated by two 1000 watt lamps and appeared to be uniformly lit - my digital camera proved this ;-) ..

109381

It's quite frustrating, not matter what I do, the result doesn't even change much - I always get these blotchy negatives. Nevertheless I would really like to work this out since I've seen very nice negatives developed in diafine but can't imagine what I'm doing wrong .. Maybe I should walk away from Diafine and try another developer - I would like to use a hybrid workflow, is there a developer which is particularily suited for scanning?

Thanks,
Christoph

Leigh
28-Jan-2014, 15:36
I did not presoak this time
Hi Christoph,

You absolutely CANNOT use a presoak with Diafine. It says so in the instructions.

Diafine works by absorbing Part A into the dry emulsion, then having Part B work on that chemistry.

I realize that does not pertain to the current example.

What film? Is it fresh (before the expiration date)?

This really has me puzzled. I've developed thousands of negatives in Diafine with no problems.

- Leigh

zechi
28-Jan-2014, 16:16
Hi Christoph,

You absolutely CANNOT use a presoak with Diafine. It says so in the instructions.

Diafine works by absorbing Part A into the dry emulsion, then having Part B work on that chemistry.

I realize that does not pertain to the current example.

What film? Is it fresh (before the expiration date)?

This really has me puzzled. I've developed thousands of negatives in Diafine with no problems.

- Leigh

I know that I'm not supposed to do a presoak - and I didn't this time. I presoaked before because I got uneven developement without it and wanted to give it a try .. but with the negative I attached to my last post, I exactly followed the box instructions. The film is Fomapan 100 and it is not expired and has always been in the fridge, in a zip loc bag ... maybe it's the water? I used distilled water for mixing the chemicals and also for the final rinse with the wetting agent. But I used tap water for rinsing after B .. We have quite hard water here, maybe I should try with distilled water?

Leigh, how do you develope your 4x5 sheets in diafine? in a tank or tray? I tried tray developement too, but with the same poor result ..

Christoph

Leigh
28-Jan-2014, 16:30
Hi Christoph,

The tap water after Part B should not matter, as development is complete by that time.

I've never used distilled water to mix my developer, but it does not hurt to do so.

I'm sorry. You mentioned the film type in your first post and I missed it.
I'm not aware of any issues with Fomapan. I don't use it, but I know many people do without any issues.

I use square tanks or trays, depending on how many films I need to develop.
The tanks will hold 12 sheets, which is more than I can do conveniently in trays.

I did use a Nikor round tank for a while, but found it difficult to load.
Also, the fill/dump time was excessive IMO.

I find your problem to be particularly aggravating because I can't explain it.

Regarding agitation...
Diafine is a compensating developer. Developers of this type work by exhausting the developing agent in areas of high negative density, which is why they want very little agitation. Vigorous agitation replaces the active chemistry across the entire negative very frequently, which defeats the compensation action.

You can use more vigorous agitation if needed, but you will lose the compensating effect.

- Leigh

Kevin J. Kolosky
4-Feb-2014, 08:01
why is Diafine so expensive?

Leigh
4-Feb-2014, 08:28
why is Diafine so expensive?
Huh?

It lasts forever.

You top off both parts with fresh from stock to replenish.

- Leigh

BetterSense
4-Feb-2014, 11:00
My last batch of Diafine was mixed in 2009. It had dwindled from a gallon to less than a litre from attrition when I dumped it in 2013 to move. It's very cheap on a per-area basis, but even so I haven't brought myself to spring for a new gallon.

Leigh
4-Feb-2014, 11:12
It had dwindled from a gallon to less than a litre from attrition when I dumped it in 2013 to move.
The standard replenishment technique requires that you start with two bottles full to the brim, or with a volume that you can measure accurately.
That volume is your working stock, used for actual development.

After each development session, you add enough fresh Part A stock solution (from a separate stock bottle) to restore that original volume, noting the volume of fresh stock required to do so.

You then add the same amount of fresh Part B stock to its storage bottle, then return enough used Part B to restore its full volume, discarding any excess.

You can continue this regimen indefinitely. When you run out of fresh solutions, buy another 1-quart box and mix it.

- Leigh

Renato Tonelli
5-Feb-2014, 07:40
Leigh - Are you following the box instructions as far as the Exposure Index goes for Diafine and LF?

I have been using Diafine (and sometimes its cousin Acufine) with 35mm Tri-X for close to 20 years (as per instructions on the box) and I am tempted to try it with 320TXP (4x5 & 5x7) just for kicks... I need a little encouragement...

Leigh
5-Feb-2014, 07:51
Hi Renato,

I shoot everything at box speed. I don't use any film faster than 100ASA.

Diafine is a compensating developer when used with minimal agitation as instructed.
As such it works well with films shot at lower EIs than the box values.

- Leigh

Renato Tonelli
5-Feb-2014, 10:56
Leigh - thank you for your generous advice.

blueribbontea
5-Feb-2014, 12:40
zechi: Could your film be the culprit? You might try developing an unexposed sheet in dilute Dektol or some other developer...troubleshooting.

Bill

zechi
7-Feb-2014, 14:30
zechi: Could your film be the culprit? You might try developing an unexposed sheet in dilute Dektol or some other developer...troubleshooting.

Bill

No, I don't think it's the film, I developed a test shot in fomadon excel (xtol) and it came out fine .. I don't know why I cannot manage to develope with diafine ..