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wheresclark
6-Apr-2016, 04:48
So I just started using Pyrocat-HD as my new developer. So far the results have been weird. The last two negatives I developed end up with this weird uneven development. I'm not sure what info you'd need to diagnose the problem, but I developed the 4x5 film (delta 100) in 5x7 trays using 500ml of Pyrocat-HD (2:2:500) for 40 minutes @ 71 deg F with 30 seconds initial agitation, followed by 10 seconds every 10 minutes. The 5x7 trays have not been a problem in the past . There are four things I've done differently which may be the culprit.

1. I pre-soaked the negative for 5 minutes in water. This is what I've been told to do with long development times like this.
2. I used a new developer (Pyrocat-HD at 2:2:500 ratio).
3. I used a new fixer recommended for Pyrocat (TF-4).
4. During the wash, I ran the negative under the shower with the lowest water pressure I could whilst refilling the tray with fresh water. I did this about four times. If you look closely at the negative, you can also see that the majority of the image is affected by what I think is the water droplets hitting the soft emulsion.

So I have two probems which I'm hoping someone could enlighten me how to avoid.

1. The weird blotchy sky that. Is this an effect from not enough agitation?
2. The center of the image that looks like it might be a product of the water droplets. Very unsharp.

Your help would help so so much.

Clark149262

Jan Nieuwenhuysen
6-Apr-2016, 05:51
The 'weird blotchy sky' looks like reticulation to me. Hard to tell on the monitor, but that is my first impression. Reticulation is what happens when there is a sharp increase or decrease in temperature when processing film. The gelatin and the base layer contract/expand different when cooled down/heated up. If you put the film from 71F chemicals straight under a cold shower that might explain it.
Apart from that, soft emulsion is, eh, well... soft. Showering it might indeed damage it. The bright side is that now you know, so that mistake you will not make again :)

koraks
6-Apr-2016, 06:51
Uneven development due to lack of agitation. Your semistand development approach is asking for trouble in my opinion. I have had nothing but problems whenever I've tried developing with minimal agitation.

IanG
6-Apr-2016, 07:28
Uneven development due to lack of agitation. Your semistand development approach is asking for trouble in my opinion. I have had nothing but problems whenever I've tried developing with minimal agitation.

I agree poor agitation. A pre-soak doesn't really help and things can be worse if you have hard water, commercial developers contain sequestering agents to counter hard water. I was having problems with air bells while in Turkey using Pyrocat HD and now add a very small amount of photo-flow to my Part A when I make up my. stock solutions. deionised I use tap water to make up the working solutions. I use inversion tanks for 5x4 processing and did visual tests - taking the top off the tank, the level of Photo flo is enough to prevent airbells but way below the level that would cause foaming.

Ian

Harold_4074
6-Apr-2016, 16:57
The 'weird blotchy sky' looks like reticulation to me.

Having (several times, but as a kid :) ) reticulated film, and with an understanding of the physical chemistry, I can say with some confidence that this is not reticulation. Without going into the physics involved, let me point out that reticulation would probably have a lateral spacing which is some small multiple of the coating thickness.

jose angel
7-Apr-2016, 00:43
Is this a negative scan, or a print scan?
My "reticulation experience" says this reticulation is too large to be real reticulation. I may be wrong, thanks God my reticulation failures are pretty scarce :D. And I`m not used to pyro developers.
BTW, I have experienced a similar issue printing on pretty updated papers.
Also, it reminds me the effect of really dirty condensers.

Doremus Scudder
7-Apr-2016, 01:26
I'll agree with those who say your problem is lack of agitation and definitely not reticulation (which is a much, much smaller crazed pattern, not large stripes). The stripes to me look very similar to the random stripes/striations of oxidation that occur on the surface of a staining developer like PMK or Pyrocat when you let it sit in the tray undisturbed for a few minutes. A similar thing is likely happening to the developer at the surface of your negative as it is sitting undisturbed.

I don't know what you are after with your reduced agitation scheme, but if it is just edge effects (Mackie lines) then you can try more frequent agitations during the first half of development (at least once every 30 seconds) and then reduce this to once per minute during the last half. I get very pronounced edge effects this way with PMK and very even development.

Best,

Doremus

Cor
7-Apr-2016, 01:37
In my limited experience with stand and semi stand: I do not think that a tray is the correct approach. It might be that the film might floats to the surface during the 10 minutes stand, causing the pattern. When I do semi stand with Pyrocat I put the film in a tube (BTZS tubes or similar) and fill the tube almost completely, and than semi-stand develop.

good luck,

Cor

wheresclark
7-Apr-2016, 18:06
Thanks for all your thoughts everyone. To answer Jose, it was a negative scan not a print scan. Doremus, I was trying to get increased edge effects, thanks for your idea with early agitation.

After a few more tests I believe the large stripy pattern is from too little amount of developer in trays. The shallow depth of liquid, combined with a long time sitting still wthout agitation meant the pattern that forms on top of the developer was affecting the negative. I did the same thing last night, but with much more liquid and had better results.

The other problem I had with the dotty/unsharp grain was because I scanned the negative too early and it must has still been drying (although it looked dry from inspection). I scanned the same negative again today and the dotty/unsharp grain had dissapeared and is now normal as expected.

What have a I learned from this? Well, wait until your negatives are COMPLETELY dry before scanning. And that if I want to experiment with stand/semi-stand I should probably get myself a tank or tube. I backed the SP-445 project on kickstarter (new daylight tank design) so will wait until it arrives in a month or two before attempting longer development times again.

Thanks again.

Clark

AtlantaTerry
7-Apr-2016, 21:17
Wheresclark:

I also do not think the problem is with reticulation. I my research and experience, reticulation problems are on the microscopic level so the images look grainy. Your problem is something else.

John Berry
9-Apr-2016, 21:17
Your problem is in tray developing. You now have the evidence as to why pyrocat and minimal agitation MUST be done vertical with hangers.

djdister
10-Apr-2016, 09:21
Definitely not reticulation. Looks more like part of the sheets of film were stuck together for some amount of time during processing.

wheresclark
10-Apr-2016, 17:14
Your problem is in tray developing. You now have the evidence as to why pyrocat and minimal agitation MUST be done vertical with hangers.

You said it John. Until I get myself a daylight tank, I'll stick to 9 min processing time with 10 secs every min.

Clark