OP
OP
Agitation, surge, and uneven development?
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OP
OP
Yes again for what it’s worth I’m still seeing the same effects/artifacts as in your original negative images.
OP
OP
Thank you. I am happy to learn that at least one other person can see the issue.
To solve some mysteries about film agitation I found article from "Darkroom Photography" Shake it up, March-April 1986 very helpful.
But, what are our policies here for posting copyrighted material?
But, what are our policies here for posting copyrighted material?
MattKing
Moderator
The effect is more visible in your more recent posts.
Which in turn makes me now think that the flow of developer is uneven - more at the channel edges of the reels, and less in the middle.
I'm thinking that your agitation is not sufficiently randomized - it seems to be imparting extra to the parts of the film nearest the spirals, and leaving the centre of the film less replenished with fresh developer.
Try increasing the randomness of the twisting and inverting part of your inversion technique.
Also try leaving a bit more air in the tank - the developer needs to cavitate more as it moves through during each inversion.
Which in turn makes me now think that the flow of developer is uneven - more at the channel edges of the reels, and less in the middle.
I'm thinking that your agitation is not sufficiently randomized - it seems to be imparting extra to the parts of the film nearest the spirals, and leaving the centre of the film less replenished with fresh developer.
Try increasing the randomness of the twisting and inverting part of your inversion technique.
Also try leaving a bit more air in the tank - the developer needs to cavitate more as it moves through during each inversion.
MattKing
Moderator
If there is a link you can post, that is best.
OP
OP
Thank you. I do twist the tank 1/4 turn before each inversion, but usually always in the same direction. Maybe I'll try twisting in the opposite direction every other time(?)
Up until yesterday, I have been leaving about 1/2-inch of air at the top of my 32 oz. tank. Yesterday, I filled the tank more completely, but I have not yet printed those negatives or tried to digitize them, so Il don't know if that had any effect.
It's definitely uneven development due to agitation problems.
120 film is finicky about agitation. You're seeing more development at the edges than the middle of the film. It might be overagitation, but again, might be underagitation. You'll have to put in the time experimenting with agitation techniques and find what works for you.
What you do know is that the edges are getting more agitation than the middle. Go from there and test.
Good luck! I had a time of it figuring it out myself, but it was worth it.
Another approach: Find someone who doesn't have this problem and has perfectly evenly-developed negatives and see what equipment, fluid volume and agitation techniques they use. That might help.
Best,
Doremus
120 film is finicky about agitation. You're seeing more development at the edges than the middle of the film. It might be overagitation, but again, might be underagitation. You'll have to put in the time experimenting with agitation techniques and find what works for you.
What you do know is that the edges are getting more agitation than the middle. Go from there and test.
Good luck! I had a time of it figuring it out myself, but it was worth it.
Another approach: Find someone who doesn't have this problem and has perfectly evenly-developed negatives and see what equipment, fluid volume and agitation techniques they use. That might help.
Best,
Doremus
MattKing
Moderator
Twist while you invert - just grab the tank with both hands, one on the bottom and the other on the top, and rotate your arms and wrists so that the top hand becomes the bottom, and vice-versa.
When you do that, your wrists will naturally impose a twisting motion on the tank.
And I wouldn't have tried increasing the volume - I expect that will tend to reduce the randomness of the flow.
For what it's worth, I do the same but turn 1/7 not 1/4, in the hope that the result is a little more random. I thought maybe your type of reel might be part of the problem, but seeing that you're using steel reels I expect that the amount of interference of the film edge by the reel would already be minimal (compared to the higher flanges of plastic reels).
My agitation is just a gentle turn over, enough to move the developer around quite a lot, air space enough to ensure adequate liquid movement. Then again after the twist. Then I leave if for a couple/few minutes. Initial agitation 2 minutes constant similar turning over. I don't detect any unevenness in sky density.
OP
OP
Good idea! There are about 5-6 other students in my class, and as far as I know, none of them are having the same problem. One is retired from a career as a professional product photographer, so very experienced. Next time one of my classmates is developing film, I will shadow them. I did recently observe the class instructor as she demonstrated development in diy coffee+ascorbic acid. I didn't notice that she was doing anything much different from what I am doing, but at the time I no reason to pay more than average attention.
I find it strange that none of the maker's of developers seem to mention any of these sophisticated methods of agitation to prevent runswithsizzers problem. Doremus suggests that the OP finds someone who have doesn't have this problem and learn from that person
Well as I said earlier I am one such person and I do what Ilford recommends. It's a pretty straightforward up and down agitation
I may have been lucky not to have been troubled by runswithsizzers problem by normal agitation and I expect to be told that soon but I still can't help feel that we appear to have eliminated all other causes and may be starting down the rabbit hole of agitation being the only cause
I note that there are even sophistications on a more sophisticated method. The danger with this is that all those with their own but slightly different agitation techniques may result in runswithsizzers facing the same kind of problem as Bob Hope in Son of Paleface when he gets advice on how to win the gunfight that he has been challenged to
A bit of late night humour except for our Antipodean members where it is early morning
Well as I said earlier I am one such person and I do what Ilford recommends. It's a pretty straightforward up and down agitation
I may have been lucky not to have been troubled by runswithsizzers problem by normal agitation and I expect to be told that soon but I still can't help feel that we appear to have eliminated all other causes and may be starting down the rabbit hole of agitation being the only cause
I note that there are even sophistications on a more sophisticated method. The danger with this is that all those with their own but slightly different agitation techniques may result in runswithsizzers facing the same kind of problem as Bob Hope in Son of Paleface when he gets advice on how to win the gunfight that he has been challenged to
A bit of late night humour except for our Antipodean members where it is early morning
One of the more arcane recommendations I was given concerning agitation was each time after inverting the tank to rotate it in the direction that causes the leading edge of the film in the reel to be pushed into the liquid. In my experience the leading edge of the film almost always curls longitudinally to almost contact the next row it didn't seem it would have much effect but I've been doing it anyway.
OP
OP
A month ago, I thought I knew how to develop film. Since 2019, I have processed more than 40 rolls of 135 film without noticing any uneven development in my negatives. Over the years I have used a couple of different variations in the number and frequency of inversions, but my basic technique, per inversion, has not varied by much.
Considering that four different normally reliable sources offer different (and sometimes conflicting) advice about agitation, it's hard for me to believe that minor variations in technique should make all that much difference.
oops! posted before complete. edited to add:
I made the following chart to summarize what four normally reliable sources recommend for agitation ...
Anchell and Troop say any agitation must be for at least 10 seconds, and 5 seconds will not produce enough movement.
Trying to sort-of juggle these recommendations into some kind of aggregate, my feeling is, I have not been agitating enough. I have been starting with a 30-second initial agitation, but after that (based on a class handout), I have been inverting only two times per minute, which takes me only about 5 seconds.
Considering that four different normally reliable sources offer different (and sometimes conflicting) advice about agitation, it's hard for me to believe that minor variations in technique should make all that much difference.
oops! posted before complete. edited to add:
I made the following chart to summarize what four normally reliable sources recommend for agitation ...
Anchell and Troop say any agitation must be for at least 10 seconds, and 5 seconds will not produce enough movement.
Trying to sort-of juggle these recommendations into some kind of aggregate, my feeling is, I have not been agitating enough. I have been starting with a 30-second initial agitation, but after that (based on a class handout), I have been inverting only two times per minute, which takes me only about 5 seconds.
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MattKing
Moderator
The advice actually doesn't really conflict, in its essence.
The primary advice is to make sure that there is enough even but randomized movement of the liquid in the tank.
The way to get to that goal is much more difficult to explain in words or pictures than it is to show in real (or perhaps reel) life.
The primary advice is to make sure that there is enough even but randomized movement of the liquid in the tank.
The way to get to that goal is much more difficult to explain in words or pictures than it is to show in real (or perhaps reel) life.
Exactly. You're being too gentle/cautious.
Your new examples are indeed compelling.
OP
OP
All of my recent 120 film has been developed in Kodak D-76 at 1+1.
MattKing
Moderator
And quite likely, in a manner that doesn't add enough randomized movement.
The developer is sitting almost stationary near the centre of the film, while the agitated developer is flowing only in and near the steel reel channels, adjacent only to the film rebate.
My reels never move in my tank. I have a 1x120 AP tank which fits 1 120 reel. The reel is securely kept in place by a round plastic pin. I also use a 2x120 Paterson tank, and I use it only when it's at full load - 2 x 120 reels. Nothing moves around. I would try removing this variable (reels moving around) as it might be of importance to what you're seeing here.
Also - I am just as gentle/cautious with my inversions and I never get this effect. 2 'very gentle' inversion at the beginning of every minute is what I do. I also use TLRs though not this particular one.
Another point - is this a new - to you - camera? Have you ever taken pictures with it that didn't show the issue? I'm wondering whether there might be issues with the pressure plate. Top and bottom of each negative will be held flat by the rollers. Left and right of the negative will rely, for flatness, entirely on the pressure plate. Could this be a contributing factor?
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I usually develop in D-76 (1+1), too, and the developing times are usually over 8 minutes for most combinations of Film/ASA rating I can think of. From this table, I use a slightly modified Steve Anchell agitation method (this really is my dad's agitation method, just stuck with it
): I don't twist the tank back, just twist in one direction and never had any kind of uneven development (me from 20 years or so, dad from the early 70s ), so maybe this method (or a variation on the theme) is worth a try given that it would comply with your typical development times.-
- rippa_the_hutt
- Deleted
MattKing
Moderator
The OP is using steel Hewes reels.
I used the Kodak way for every reel I've ever developed and never had such a problem as you have shown, and the problem is definitely clearer in the latest examples. Five to 7 180 deg inversions in 5 seconds is fairly rigorous imo.
edit: should've added using SS tanks and reels
edit: should've added using SS tanks and reels
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Thanks Matt. Are the reels in this design supposed to move around?
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