Processing difficulties

[Tony-S]

I'm having an issue with my 120 processing I hope someone can help me isolate. On the last few of rolls of B&W film (Acros, Pan F+, Delta 100) I'm getting inconsistent development at the top of the rolls, and sometimes both the top and bottom. This only happens with B&W film that I develop. The color film (Ektar and Velvia) processed by my local lab do not exhibit this, so I'm sure it's my developing and not the camera (Bronica GS-1 6x7 back). I've used both plastic and stainless steel reels. The attached image was shot on Fuji Neopan Acros 100 at 100 and processed in Perceptol (1+2) for 16 min at 75F. Any ideas?

TIA.

 

[srs5694]

Assuming the light (too dark in negative) area at the top is the problem, then it's likely an agitation issue. Proper agitation can be tricky to describe, and depends to some extent on the tank you're using. Personally, I agitate continuously by inversion for 30 seconds, then do four or five inversions every 30 seconds thereafter. Each inversion (complete turn upside down and back rightside up) takes about 1 second, or maybe just a bit more. After every agitation cycle, I rap the tank to dislodge bubbles and give it a slight twist (about 90 degrees).

I've seen descriptions of agitation that are more and less vigorous than mine. I've seen claims that under-agitating or over-agitating can produce the problems you seem to have. I recommend you shoot a few test rolls and try radically altering your agitation routine. You may also want to check YouTube; I'm sure there are demonstrations that could be more informative than a written description, but I don't happen to have any links bookmarked.

Another thought: Are you using inversion agitation, agitation via a rotating stick, or some other method? Most people seem to prefer inversion agitation, but some people prefer using the rotating stick. Most (all?) stainless steel tanks lack the stick for that style of agitation, although there are SS reels for some plastic tanks. A few (mostly elderly) plastic tanks aren't built for inversion agitation. Most modern plastic tanks can use either method. If you've got such a tank, you could switch from one method to the other.

 

[Rick A]

It does sound like an agitation problem, varies between top or bottom, means that the reel is loaded one way or the other at random. Standardize your agitation method to 180 degree inversions with a twist continuous for the first 30 seconds, then 5-7 (10 seconds) on the minute(every 60 secs). Make sure the tank is topped off with chems, I always use a little more than specified, and have a little spillover when filling my tanks.

 

[darkroomphotography]

I agree, its agitation problem.
Test diferent times of agitation.
Like Ralnphot's method or some others like the 1st minute continously and then 2 every 30 seconds.

 

[Dan Henderson]

I concur with my esteemed colleagues. I had a similar problem that was solved when I slowed my agitation way down.

 

[clayne]

It does sound like an agitation problem, varies between top or bottom, means that the reel is loaded one way or the other at random. Standardize your agitation method to 180 degree inversions with a twist continuous for the first 30 seconds, then 5-7 (10 seconds) on the minute(every 60 secs). Make sure the tank is topped off with chems, I always use a little more than specified, and have a little spillover when filling my tanks.

We've probably discussed this same issue in two other threads this week, but the short is that one should NOT top of their tank. The liquid needs to move. It has more trouble actually doing that if it doesn't have airspace to displace with. Filling to the brim == gradient density effect on the edges which sucks even more than improper agitation because it's a lot of work to fix after the fact.

 

[Anscojohn]

Being the dinosaur I am, I use standard ASA agitation. I have no reason to change.

 

[Rick Jones]

Your sample appears much as some of my 120 films of the past. More specifically, my problem was uneven development which resulted in increased edge density. Never would I be so presumptuous to state that I have solved the problem but I can say I'm currently holding the gremlins at bay. If the previous posts don't solve your problem my suggestion is you give us a detailed description of the tank(s) you are using (I favor ss), its capacity, exactly how you are agitating and what type of reels you use (did I say I favor ss?). Also how much developer you are using for each roll. Sometimes a problem can be corrected by adjusting one or two details. As simple as film development is the devil can be in the details!

 

[ic-racer]

Hard to know for sure. A color scan of the entire negative up to and beyond the film edge can be better, as the foggyness from inadequate fixation or inadequate anti-halation removal can also cause excess tinted density.

Having said that, my guess, based on the info presented is that the developer is going to exhaustion during the process. So,...

How much developer per roll are you using?
1000ml of Perceptol processes 4 rolls of 120. So, it takes 250ml for one roll. If you are diluting to 1:2, you need a tank capacity of 750ml. Is that what you are doing? Are you using empty reels to take up the extra speace? How full is the tank. If you have, say, only 750ml in a 1000ml tank the solution could swish around too much as you agitate. The tank should be filled to its capacity.

 

[Jeff Kubach]

Looks like agitation problems to me also.

Jeff

 

[Tony-S]

Thanks to all who responded. I'll give the inversion method a try for the agitation. I just have to find a cap for my ss tank's lid...

 

[George Collier]

I have found 120 film to be temperamental to agitation techniques, depending on the developer. And what works for some folks won't for others.
My experience is:
HC110 is very forgiving, using standard interval agitation.
Rodinal semi-stand is fussy, but worth it, for me. I had much trouble with what some call "surge" - what I see in your scan, occurring on either the top or bottom of the reel(or both, but usually the top), and I tried a lot of things before finding the right combination, for me.
As some suggested, shoot some test rolls, and do everything as consistently as you can (reel always positioned the same way in the tank included).
I agree that the tank should not be full to allow the chems to move around. I measure 420ml every time. I know from measuring for my Kinderman tank and Hewes reel that this is comfortably enough.
There's more to say, and you can find more commentary on this by searching this forum for "surge".

 

[pentaxuser]

Seems like several threads going on this topic (including my own!). One thing I keep noticing is we don't seem to have a concensus on whether or not to fill the tank or leave some space. Clayne says leave some space, which to me seems logical. But others are still saying fill to the top.

Not sure who is saying fill to the top if this means that the liquid doesn't have the chance to move. Fill a bottle to the top of the neck with water and add a tiny quantity of coloured liquid then agitate with inversion and see how long it takes to disperse the colour. Then do it again with some space and time again. You will be surprised as how little agitation is possible in a full container.

What I think we should be saying is fill the tank with whatever quantity of liquid the manufacturer of said tank specifies. If there is no specification then add water to a tank until it covers the reel then decant into a measuring jug. However much liquid you get is the quantity of developer and fix to use.

Some tanks allow quite a bit of headroom so even if "overfull" will still allow more agitation than others where headroom is less. A Jobo v a Durst is a good example of this more and less headroom so the only safe route is fill to cover the reel.


pentaxuser

 

[tkamiya]

I don't know exactly what kind of tank you use but....

I use stainless steel tank with plastic lid. I usually fill developers to the max but not always. With my tank, when I do inversions, the reel has some room to move up and down causing the fluid to circulate. I never experienced problems like ones shown here.

Is your developer fresh and active? It could also be a problem with fixer not clearing sufficiently. Is "out of frame" area nice and completely clear?

 

[fotch]

Fill to the top of the reel, not the top if the inlet. If you don't know how much fluid that will be, check it by putting the reel/s into the tank, no lid is needed, and fill until you top the top reel. Then pour this out into a measuring cup. Observe the ounces needed. Now your done. :rolleyes:

 

[Tony-S]

My ss tank covers the reel with about 420 ml and I use 450 ml. My developer was 1+2; 150 ml Perceptol, 300 ml water. The reel is recessed inside the tank with about 2 cm between the top of the reel and the top of the tank, so there is air at the top of the tank but the film is completely covered. The developer is about 2 months old. As I agitate (swirl), developer seeps out of the tank around the lid. I'll do the inversion method next to see if that works.

 

[Anscojohn]

Thanks to all who responded. I'll give the inversion method a try for the agitation. I just have to find a cap for my ss tank's lid...

**********
It'll leak anyway.......

 

[Anscojohn]

Agree. The liquid needs space to move.

***************
Yup. And then you can get surge marks through the sprocket holes and over-development on the top edge of roll film!!

The liquid in a small tank needs no more room to move than it does in the gallon and three and a half gallon tanks used for sheet film, for criminy's sake. All we do is move the hangers in the solution. (well, in and out, really).
The gentle "click" sound as my ss reels move in the solution tells me they are changing position, bringing new solution into contact with different exposure level parts of the film.
I used to tell students that the sound of that click should be a bit less than the sound of gently popping open a snap-open beer can. They immediately get it.
The half-turn or so Rainphot mentions helps move the solution. I bet even the healthy thump I give my ss tanks with the heel of my hand at the end of agitation helps gently move the solution as well.
Since I began developing film in 1961, I have filled the tank till I see the developer. That is the way I was taught because it worked for those experienced guys who taught me.
With the exception of adding the half turn mentioned by Rainphot (and only in the last ten years or so), I have followed a strict ASA developing regime.
To the best of my knowledge and recollection, I have never had any of the problems lamented upon by OP and other posters.

 

[Thomas Bertilsson]

With the exception of adding the half turn mentioned by Rainphot (and only in the last ten years or so), I have followed a strict ASA developing regime.
To the best of my knowledge and recollection, I have never had any of the problems lamented upon by OP and other posters.

I agree fully that the problems appear to be about agitation and not getting the liquid within the tank to move across the film plane uniformly.
I had some problems like this a couple of years ago that nearly caused me to tear all my hair out. As it turned out, getting agitation under control is exceedingly important for consistent results.

You need enough of an air pocket in the tank for the liquid to be able to move, but you also need enough developer so that it doesn't move around too quickly. For a particular tank you use, always use the same volume. It's trial and error to establish what that volume is.
For my purposes, whether I use the full capacity of my 4-roll 120 stainless steel tank or just process one roll, I fill it to the same volume, which is 1,750ml. I measure this every time I process film. And I lower the film into the already full tank, then put the cap on and start agitating immediately.

Basically, make enough room for the liquid to move around, agitate well, but make sure it's not too vigorous. John's description of how it should sound by opening a soda (barley soda) can is very good.

 

[Tony-S]

I'm also still unclear on the amount of stock Perceptol required to develop one roll of film. 250ml seems like a lot, and leaves virtually no room for any of Ilford's recommended dilutions without switching to a much larger tank.

I don't understand what you're saying. I used 150 ml of Perceptol stock plus 300 ml of water (1+2, 1:3) and that provided coverage of the film throughout development.

 

[MattKing]

I don't understand what you're saying. I used 150 ml of Perceptol stock plus 300 ml of water (1+2, 1:3) and that provided coverage of the film throughout development.

It is not enough just to cover the film. You also need to have enough active chemistry to actually develop the film.

From what others have said, you need at least 250 ml of stock Perceptol before dilution in order to have enough active chemistry to make development happen properly. If you start with just 150 ml of stock, it will exhaust itself before finishing the job.

If you want to use more dilute working solution, with Perceptol, you will need to use a bigger tank.

 

[pentaxuser]

I'm also still unclear on the amount of stock Perceptol required to develop one roll of film. 250ml seems like a lot, and leaves virtually no room for any of Ilford's recommended dilutions without switching to a much larger tank.

Yes I'd agree this is the second point on which there isn't a consensus. There was a whole thread on this second point a couple of months ago. One of our APUGers from Germany wanted to know what the minimum stock quantity of Perceptol was to properly develop film. I forget whether this was 120 or 35mm. Ilford actually seems to say that it doesn't matter presumably on the basis that the area of either is roughly equivalent. Well it is a very rough equivalent. 36 frames of 35mm is about 310 square cms whereas a 120 in 6x6 is maybe 340 square cms or a little more.

Anyway if we accept that a 120 is only a little more than a 36 frame of 35mm then I'd make two points.

I have had regular success with 1+1 with D400, D100 and Fuji Neopan in 35mm in a Jobo tank which means 120 mls of stock using inversion.

I have had success with 1+3 in HP5+ in the same tank which means 60mls of stock.

A guy called John Tinsley wrote a very successful book on rotary processing including using Perceptol at 1+1. He had doubts about any dilutions beyond 1+1 being adequate but in rotary processing you use only 140mls so at 1+1 this is again 70mls of stock.

If we assume I was pushing at boundaries when using only 60mls of stock there would still appear to be good evidence that 70mls works and even if we say that in small tanks 1+1 is the upper safe limit for Perceptol then this is still only 120mls of stock.

All a long way from 250mls minimum and yes you are right that on this basis and using 1+3 the smallest tank has to hold 1 litre! It begins to sound incredible to me that 250mls is the minimum but you pays your money and takes your choice.

pentaxuser

 

[Tony-S]

It is not enough just to cover the film. You also need to have enough active chemistry to actually develop the film. From what others have said, you need at least 250 ml of stock Perceptol before dilution in order to have enough active chemistry to make development happen properly. If you start with just 150 ml of stock, it will exhaust itself before finishing the job.

That seems contraindicated by Ilford's data sheet for Perceptol:

Before starting to process prepare the appropriate volume of all the required process solutions according to tank size and number of films to be processed together. The solution volume must be enough to cover all the spirals used.

This is why I went with the volume I used (they even recommend up to 1+3). It also recommends inversion for 10" on the minute (which seems to be the consensus here).

However with Perceptol if you take Ilford's publication literally it could be interpreted as requiring 250ml of Perceptol stock per roll.

I think I missed that in their data sheet - can you tell me which page it's on? I see 250 ml referenced if the developer is reused, but I use once and discard.

Thanks again to both of you.

 

[Anscojohn]

My ss reel stays on the bottom of the tank during inversion because I use a second reel above it as a spacer.
***********
Sure. We all do that. But there is still movement of the reels. Just enough movement, methinks.

That is for the most part what eliminates surge. Surge is most commonly caused when the reel moves through the solution.
**********
Or moves too much; or the solution moves to much.

I've never had that problem, or over-development on the edges.
********
Nor have I.

I've tried filling the tank to overflowing, and leaving about 1/2 inch air space, using the same agitation technique, and to be honest I did not see any difference.

Upon reflection, an added reason fill the tank is that I replenish my developer and the less exposure to air, the better. But the key to your approach is consistency.

But I still leave the 1/2 inch just because I assume it makes the most sense.
************

As above, be consistent.


So back to my original point, we don't have a concensus in this forum as to whether the tank should be filled to the top or not.
*******
The consensus for me was established by the experienced old lab rats who taught me in the early 1960s. Their's was a wealth of knowledge I still value.

 

[MattKing]

Tony:

As several of us have said, it isn't just the volume of working solution that matters, because if you are going to dilute chemistry, you have to first start out with enough chemical activity to do the job. Most commonly one refers to the manufacturer's recommendations about capacity to determine how much stock solution is enough. Then one dilutes that amount of stock solution (or more) to the dilution one intends to use.

As you note, the Ilford worksheet suggests 250 ml per roll, but only in the context of re-using developer. That section of the worksheet then goes on, however, to sort of make clear that in addition to being limited to 4 rolls per liter of activity, one must also take into account the effect of the "release (of) halides and other by-products into the developer that act as a restrainer on the development of subsequent films." That section then goes on to suggest that one increase the developing time for each subsequent roll, but that no more than 4 rolls be developed per liter.

All of which says to me that there isn't enough chemical activity in a liter of Perceptol to develop more than 4 rolls.

Hope this helps.