Developing 35mm Film

BMbikerider · Mar 6, 2023

cliveh said:
May I suggest on the best method I have so far encounted to develop 35mm film?

If others can suggest a better method, I would like to learn about it.

Mine is basically the same as yours but because I use a JOBO processor but I would suggest mine is more accurate where the temperature is concerned.

I start out but mixing the right amount of developer, stop bath and fixer. I then load the film into the tank and put it to one side. I fill and switch on the JOBO and place the tank with the film inside in the shelf inside the processor and allow the water to climb up to the correct temperature. This allows the tank, film and developer to get to the right heat level before I pour in the developer. It also cuts out the guesswork if the ambient room temperature is different. This applies to both colour and B&W, but of course allow for the different temperatures required. Using rotary motion you also have to reduce the development time for B&W by 15% as suggested by JOBO. But not for colour C41, but I have no idea why! It is always 3mins 15seconds whatever the film or manufacturer.. Go work that out!

Although not strictly necessary I always use the stop bath and fixer at the same but can be 20c. +or- 5 degrees more or less.

For the final wash I use Kodak Fotoflo wetting agent or a final rinse and almost never get drying marks or dust when I hang them up for drying

Don_ih · Mar 6, 2023

BMbikerider said:
That is absolutely not correct!

You should address your complaint to Kodak, not to me.

faberryman · Mar 6, 2023

cliveh said:
Yes Matt, I fully agree, but I still think my original post is the best method of developing a 35mm film.

Everyone thinks their way is the best way or they wouldn't be doing it that way. They all involve putting the film on a reel, putting the reel in a tank, and putting chemicals in the tank. That still leaves plenty of room from personalization.

Don_ih · Mar 6, 2023

faberryman said:
Everyone thinks their way is the best way or they wouldn't be doing it that way

I don't think my way of doing anything is the best way.

Hilo · Mar 6, 2023

There exists no best way to develop film.

There also exists no best way to print.

Luckily, we have freedom of how we do all that.

VinceInMT · Mar 6, 2023

Regarding temperature, my tap water is just above 42 degrees F this time of year and my darkroom stays about 58-60 degrees F (which I find very comfortable). I have a microwave in there and use it to warm things up, usually to 68 degrees F.

George Collier · Mar 6, 2023

I live in Richmond, VA and my darkroom varies from 60˚ - 80˚ F, winter to summer. I have a temperature controlled valve, but the temp will go only as low as the cold water, more an issue in the summer. I keep cold water in a fridge for summer processing (both tap water and distilled).
I have a good time/temp combination for the films I use (Trix - maybe soon to be HP5, and FP4) and Rodinal 1:60. My processing temp is 72˚ year round. (I know of no minimum of Rodinal straight up necessary for each roll of 135 - 36 exp roll of film, but would like to if there is one.)
My underlying effort, besides keeping time / temp relationships the same all the time, is to keep the film at a +/- 1 degree from developer through wash and photo flo. This to keep the emulsion from expanding and contracting, which may create unevenness in the grain pattern (some like it, some don't).
I have a long trough-like plastic tank that I use for a water jacket, and all chems are brought to temp, then placed into this jacket to maintain temperature during the process. If the room temp is above or below, I keep a graduate of cold or hot water handy to add to the jacket, all the way through both fixer baths.
In the summer I make a bucket of water at 72˚ and use the basic Ilford wash method of fill and dump, but to slight excess (my fixer is TF5, which washes out much moe easily than acid fixers.)

MattKing · Mar 6, 2023

If you use D-76 (or ID-11) with less than the recommended amount of stock solution, you are vulnerable to developer exhaustion.
It probably won't happen with every roll, because the other variable is overall negative density - dense negatives from high key subjects are more likely to exhaust developer than photos of jazz musicians in cellar jazz clubs (with the proverbial single red light bulb).
And it is not an either/or situation. As you go farther and farther past the recommendations, the consistency of your results will become less and less. And it is consistency (with a variety of differently exposed rolls) that the Kodak recommendations are aimed toward - those recommendations being aimed at commercial processors of volumes of film.
If your rolls are relatively consistent - you tend to expose film in similar situations - you may never notice the effect of using less than recommended amounts of stock D-76, because the effects of partial exhaustion may be consistent - may even be to your taste!
Localized developer exhaustion can sometimes be advantageous - there is a bit of compensation inherent in it, so if if it is combined with reduced agitation, it can result in high contrast scenes actually being better recorded.

Craig · Mar 6, 2023

George Collier said:
(I know of no minimum of Rodinal straight up necessary for each roll of 135 - 36 exp roll of film, but would like to if there is one.)

I have an original bottle of Agfa Rodinal, and for 500ml concentrate it says the capacity is between 30 to 80 135 rolls, depending upon dilution. So best case ( 80 rolls) that's 6.25 ml per roll, and worst case (30 rolls) that's 16.6ml per roll.

Unfortunately that's all it says about capacity. It does give a chart of developing times for 1:25 and 1:50, HP5 is not recommended at 1:50, so presumably it exhausts the developer more than other films?

Don_ih · Mar 6, 2023

Craig said:
Rodinal

Anecdotally, people say the minimum is 5ml. But that, conveniently, is also 1/100 of 500 ml. I never use Rodinal at that dilution, though. I like it at 1:25.

Bill Burk · Mar 6, 2023

cliveh said:
May I suggest on the best method I have so far encounted to develop 35mm film?

…

And never ever, ever after the film is fixed, washed and dryed, use a squeegee. Let the film dry naturally overnight in a bathroom or airing cabinet.

If others can suggest a better method, I would like to learn about it.

Good advice. I was thinking of all the people who say they just wipe the film with their fingers.

This is how my fingers looked Saturday after I got my darkroom running again after a winter’s break. I had to do a bit of plumbing. I had to recondition the Leonard valve’s bimetal coil spring because it had accumulated rust. I put some hoses back the way they belonged. And after a wipe-down of my sink my fingers were fully chapped.

BMbikerider · Mar 7, 2023

Don Heisz said:
You should address your complaint to Kodak, not to me.

It was not a complaint merely an observation. I am talking of practical experience whereas the Kodak figures will have a degree of safety incorporated which will save them from litigation should things be overstretched. I feel they are just being cautious.

I have yet to experience developer exhaustion using ID11 or D76, but to be honest I had not even considered it as a factor that may affect the quality. I shall continue to do as I have done for over half a century.

One thing I do appreciate with using ID11/D76 is that it has a very long shelf life after mixing and then storing in screw capped glass bottles. The last lot which I have just finished was mixed nearly 2 years ago.

Don_ih · Mar 7, 2023

I'm still marvelling over how short Bill's fingers are....

Molli · Mar 7, 2023

I'm with Maris on not trying to hold to a temperature that would involve a constant fight with the room's ambient temperature. Where we differ is that Maris adheres to that very sensible and logical practise - and his exquisite prints prove its worth - and I am a slob making snapshot family photo albums (you can tell who's in the photo? Good, job done!) so I employ my sloppy temperature control knowing I'll never sell a print.

Like Maris, I deal with Australia's extremes. There are two sweet spots in the year in Autumn and Spring when it's pretty much 20°C in the darkroom and I feel obliged to develop film and print whether I'm in the mood or not.
At the outer edges in Summer and Winter, I simply mix the chemicals with my 40°C/5°C tap water and pop the jugs into the fridge or sink full of hot water depending on the direction of travel required.

Simple, slothful and entirely stress free.

JerseyDoug · Mar 7, 2023

I develop my 35mm film using a 1 gallon jug of distilled water, a 1 liter bottle of working strength fixer and a small bottle of Rodinal, all at indoor ambient temperature.

Because I don't use tap water, its temperature, which varies greatly with the seasons, is irrelevant.

After I mix the working strength developer I put a thermometer in the graduate. When I am ready to start processing I read the thermometer and look up the necessary developing temperature adjustment on an old Kodak chart pasted inside the workroom cabinet door.

Spending no time messing with temperatures and using the Ilford film washing method lets me process a roll of film from setting up to washing up and putting everything away in less than 30 minutes.

pentaxuser · Mar 7, 2023

BMbikerider, I haven't tried D76 diluted but started my photographic life with ID11 diluted 1+1 in a 250ml Jobo tank so it was never more than 125ml of ID11 stock and my negs always seemed to be fine. They produced prints that looked fine to me - maybe I was easily pleased and I am probably still easily pleased.

Like another poster I never saw any sign of exhausted developer in cliveh's pics and this seems to be borne out by aparat's experiment and statement that there would likely to be no difference at all that you would see

Mind you I once asked Ilford for the minimum of stock needed for Perceptol and got the answer of 70ml. I had actually used about 63 ml of stock in a Jobo tank. Anymore at 1+3 and the tank overflows

Others were/are sure that I was seriously "shortchanging" myself by denying myself a better negative Maybe we are back to the explanation that I am just easily pleased but on the other hand Ilford did seem to say that 70 ml was OK which is a mile short of the minimum of 250ml of stock Perceptol that others are convinced is needed

So why mention Perceptol when it is D76 that is the main subject? Well, I simply use the example of both my experience of ID11 at 1+1 and Perceptol to illustrate that to a large extent the argument about minimum required stock levels is stuck on the same perpetually revolving roundabout as stop bath and presoak. It will revolve forever and I am sure my post isn't going to help us reach a conclusion but I make this post to ensure that the subject has balance in case we have any viewers that might benefit from a range of views

pentaxuser

Tom-Thomas · Mar 7, 2023

cliveh said:
Pour 150ml of developer into a measuring jug and measure its temperature. If it is under or over 68F/20C, make a separate jug of water to compensate for the difference. Example if the developer temperature is 18C, make the water to 22C, before adding 150ml of developer.

(1) Forgive me if I come out sounding pedantic here. I sincerely am not trying to be pedantic but I am pointing this out in the interest of accuracy.

You are assuming that when mixing equal amount of 2 different liquids (water and stock D76) at different temperature would result in a solution having a final stable temperature equaling to the mean of the two temperatures — in your example, (18+22) ÷ 2 = 20.

But that is only true if (a) the 2 liquids have the same Heat Capacity, AND, (b) they are in a closed system (i.e., heat only exchanges between the two liquids). Even if we assume that the two liquids are in a closed system, I doubt that water would have the same Heat Capacity as the D76 stock solution. You can refer to this web page for the calculation of the final temperature: https://www.tec-science.com/thermod...ing,thermodynamic equilibrium will be reached.

(2) I have never been able to completely dissolve all the D76 powder at around room temperature, no matter how much I stir or shake the solution. Kodak recommend to mix D76 at around 125° F and that's what I do and use the developer when it cools down to around room temperature (changing time to match the actual temp.)

tokam · Mar 8, 2023

I develop at ambient temps and I always have about 8 litres of bottled water inside my apartment. Summer is rarely a problem as the air-con is set to around 22 C. In winter I sometimes have to boost solution temps in a water bath.

If you are worried about temperature drift while developing John Finch of youtube Pictorial Planet fame has an approach which may help. Goes something like this:

1. Establish your target developing time according to dilution and temperature.
2. Halfway through development measure the solution temp.
3. For every 1 degree C difference from your start temperature, add or subtract 10% to overall development time.

So if you start at 20 C with development time of 10 mins, if your temperature at the 5 minute mark is 19 C then your overall development time becomes 11 minutes.

Link to the video below

cliveh · Mar 8, 2023

Tom-Thomas said:
(1) Forgive me if I come out sounding pedantic here. I sincerely am not trying to be pedantic but I am pointing this out in the interest of accuracy.

You are assuming that when mixing equal amount of 2 different liquids (water and stock D76) at different temperature would result in a solution having a final stable temperature equaling to the mean of the two temperatures — in your example, (18+22) ÷ 2 = 20.

But that is only true if (a) the 2 liquids have the same Heat Capacity, AND, (b) they are in a closed system (i.e., heat only exchanges between the two liquids). Even if we assume that the two liquids are in a closed system, I doubt that water would have the same Heat Capacity as the D76 stock solution. You can refer to this web page for the calculation of the final temperature: https://www.tec-science.com/thermodynamics/temperature/richmanns-law-of-final-temperature-of-mixtures-mixing-fluids/#:~:text=law of mixtures-,Adiabatic mixing,thermodynamic equilibrium will be reached.

(2) I have never been able to completely dissolve all the D76 powder at around room temperature, no matter how much I stir or shake the solution. Kodak recommend to mix D76 at around 125° F and that's what I do and use the developer when it cools down to around room temperature (changing time to match the actual temp.)

I understand your pedantic point, but perhaps I should of mentioned that after mixing the stock and water, I take the temperature of the 1:1 solution and if there is any variance from 20C (which usually there is not), I adjust the development time using my own time/temperature chart.

faberryman · Mar 8, 2023

cliveh said:
I understand your pedantic point, but perhaps I should of mentioned that after mixing the stock and water, I take the temperature of the 1:1 solution and if there is any variance from 20C (which usually there is not), I adjust the development time using my own time/temperature chart.

What is your own time/temperature chart, and how did you arrive at it?

cliveh · Mar 8, 2023

faberryman said:
What is your own time/temperature chart, and how did you arrive at it?

This is what I use and the original is taken from a magnified area from a time/temperature chart in an Ilford manual, followed by experimentation by me to determin these times for FP4 in D76 at 1:1

pentaxuser · Mar 8, 2023

Tom-Thomas said:
(1) Forgive me if I come out sounding pedantic here. I sincerely am not trying to be pedantic but I am pointing this out in the interest of accuracy.

You are assuming that when mixing equal amount of 2 different liquids (water and stock D76) at different temperature would result in a solution having a final stable temperature equaling to the mean of the two temperatures — in your example, (18+22) ÷ 2 = 20.

But that is only true if (a) the 2 liquids have the same Heat Capacity, AND, (b) they are in a closed system (i.e., heat only exchanges between the two liquids). Even if we assume that the two liquids are in a closed system, I doubt that water would have the same Heat Capacity as the D76 stock solution. You can refer to this web page for the calculation of the final temperature: https://www.tec-science.com/thermodynamics/temperature/richmanns-law-of-final-temperature-of-mixtures-mixing-fluids/#:~:text=law of mixtures-,Adiabatic mixing,thermodynamic equilibrium will be reached.

I had a look at the link and both the formulas and the maths needed "blew my mind" but can I ask you and others who know a lot more than I what the difference will be between the example of (18+22) ÷ 2 =20 and what the formula in the link produces

Thanks

pentaxuser

Bill Burk · Mar 8, 2023

I bring my running water to 68-degees F(20C) using a thermostatic mixing valve. I underrun it (modest stream not the gallons per minute it really needs) so it always needs fiddling. This past week I had to take it apart and clean out the rust.

But once the sink water comes in at 68-degrees (or 69 or 70), I make a water bath in a one-gallon steel pot, and put the beaker of developer in the bath until it comes up to temperature.

Sometimes I will fill the steel pot with hot water to kick start it if the developer is really cold.

Once all the temperatures are stable I will start the timer - CompnTemp - having a nominal target temperature set at 68, but no matter what the temperature of the inlet water is, the real time fluctuates according to a curve that was implemented in the Zone VI compensating timer.

Whew. Lots of words, but it’s simple like that. The development time that I choose is from Time-CI charts that I have drawn from previous tests for the contrast I feel like aiming for.

If I don’t have any particular reason to aim for a specific contrast I will do a time of 13:30 (for most 100 or 400 speed films from Kodak or Ilford). That’s what it takes for me to reach ASA parameters. (Other films get their own times like Panatomic-X and APX-25).

aparat · Mar 8, 2023

@Bill Burk Thanks for that. It's a really cool approach.

Before I converted to Jobo, I used a method very similar to what Kodak describes on p. 3-2 in the z131 document. The section concerns commercial C-41 processing, but the overall approach to temperature control can be easily adapted to one's own darkroom and processes, including B&W. I am not saying it's the best method, only that it worked for me and that I found it to be reliable and simple to implement. To make it even more streamlined, one can write a simple program that keeps track of ambient and solution temperatures and adjusts processing time in real-time. It can run on a Raspberry Pi, for example. I believe CatLABS sells a thermometer/timer with such programming included, if I am not mistaken.

Tom-Thomas · Mar 8, 2023

pentaxuser said:
I had a look at the link and both the formulas and the maths needed "blew my mind" but can I ask you and others who know a lot more than I what the difference will be between the example of (18+22) ÷ 2 =20 and what the formula in the link produces

In a nut shell, the correct calculation takes into account the different heat capacity of different substances. Heat capacity is "the amount of heat to be supplied to an object to produce a unit change in its temperature" (link to Wikipedia). In other words, the amount of heat energy released by substance A when its temperature is lowered by 1 degree isn't the same as the heat energy needed to raise the temperature of substance B by 1 degree if substance B has a different heat capacity. Therefore the final stable temperature wouldn't simply be the mean value of the 2 initial temperatures.

Developing 35mm Film

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