Replenishment of a Rodinal-type developer

[Jarin Blaschke]

Hi all:

I am a cinematographer shooting an upcoming black and white feature film on real, live black and white film. I am exploring alternatives to D-96 as a motion picture developer. I don't like the mushiness of the grain nor the flat highlights of solvent developers. I prefer a straight line to an S-curve response, highlight separation, micro contrast, resolution and acutance. For my still photography, I use a pyrogallol-metol developer and am in love with the tonality.

Unfortunately, what limits options is that a motion picture machine does not start development of all the film at the some time, but rather runs the thread of film through all the solutions, so the start of the roll is already being washed as the middle of the roll is just going into the developer. Therefore, a developer replenishment system seems to be necessary, as well as constant agitation. This system seems to preclude the possibility of a using tanning developer, which would have been my first choice by far. The oxidation products would keep accumulating. I will run tests at home in my hand tanks to see if this really is futile.

In the meantime, I am looking at what would be a second choice, which would be a Rodinal look. However I don't know if that developing agent can be formulated to work outside of a one-shot system. The motion picture machine takes 700 liters of solution, and it would have to consistently develop to the same density and gamma for a couple/few hours. Our daily footage could approach 12,000 feet on some days.

Are there any home brew Rodinal experts who can advise?

Thanks!
-Jarin

 

[Lachlan Young]

What you are describing could probably be done equally well by using the equivalent of a diluted (1+2 or 1+3) D-76 or similar - getting the sulfite level down & not overdeveloping will improve sharpness & straighten out the curve quite dramatically. Not sure however how well or easily a replenished system based on this could be achieved. Rodinal would be even more challenging I think - a full scale R&D job. Big issue is dealing with developer byproducts & their effects, which is probably why most replenished developers follow fairly similar designs.

Before you get too deep into developer formulation, have you given XTOL a shot? It seems somewhat sharper working than most of the alternatives & is designed for a replenished system.

Finally, how adjustable is the processing machine line speed & are you planning to scan/ DI the film or make a chemical print direct from the negative? I've been thinking about trying out some 5222 in 2-perf for a project, so I'll be interested to see where you go with this.

 

[Gerald C Koch]

D-96 is designed to produce lower than normal contrast, a gamma of 0.55 rather than 0.68. This is done because the negative film is printed on high contrast stock. Instead of trying to change things stay with the system that was developed.

Rodinal is intended as a single shot not as a replenished developer. Why not use a developer designed for use in automatic processors.

 

[Jarin Blaschke]

Hi Lachlan:

From what I see, the original D96 is basically D-76 with a little less sulfite (75g vs. 100g), reduced hydroquinone and a little introduced bromide. If every other avenue fails, I'll probably just ask them to just drop the sulfite levels a lot, to say, 5 or 10g/L. Useful Cine gamma is much lower than for still photography, so that should help somewhat too. Nonetheless, that is a last resort.

I found a circa 1918 p-Aminophenol hydrochloride / Sodium Carbonate cine developer, but it indicates a 1 min development time at 95 degrees!

XTOL may be economically prohibitive, as the machine uses 200 gallons of developer at a time, and we have 30 shooting days.

Most screenings will certainly be digital projection, but I hope to have some contact prints for special venues and screenings.

All these efforts are attempts to improve 5222, which always looked quite dull next to Plus X our FP4 back when Ilford made motion picture film.


-Jarin

 

[Jarin Blaschke]

D-96 is designed to produce lower than normal contrast, a gamma of 0.55 rather than 0.68. This is done because the negative film is printed on high contrast stock. Instead of trying to change things stay with the system that was developed.

Rodinal is intended as a single shot not as a replenished developer. Why not use a developer designed for use in automatic processors.

Because I don't like the solvent look.

 

[Lachlan Young]

D-96 is designed to produce lower than normal contrast, a gamma of 0.55 rather than 0.68. This is done because the negative film is printed on high contrast stock. Instead of trying to change things stay with the system that was developed.

No idea where you got this from, the 5222 data sheet explicitly states that the aim gamma of 5222 in D-96 for normal speed in cinema usage is 0.65-0.70.

The same data sheet also gives timings for 0.5 & 0.56 gamma & the curves they give might be more useful than the standard 0.65-0.70.

 

[Lachlan Young]

Another route possibly worth exploring: the metaborate buffered developers like DK-50, DK-60a - they've got a low enough sulphite content (30g/l in DK-50) to be non solvent, they're replenishable as designed, and (speaking very, very generally) they tend not to shoulder as readily as D-76 etc & tend to give more of an upswept curve. Might be worth a try/ look. Geoffrey Crawley published a modification of DK-50 for use as a one shot high sharpness developer which might also give some jumping off points for modifying the formula for greater sharpness.

If you're really determined to do something with Rodinal, Mirko at Adox/ Fotoimpex might be a useful person to ask - given that Adox now makes the official Rodinal "together with former Agfa scientists", there might be someone at Adox able to give a clear answer on the viability of making a replenishable developer that behaves like Rodinal.

 

[Jarin Blaschke]

Another route possibly worth exploring: the metaborate buffered developers like DK-50, DK-60a - they've got a low enough sulphite content (30g/l in DK-50) to be non solvent, they're replenishable as designed, and (speaking very, very generally) they tend not to shoulder as readily as D-76 etc & tend to give more of an upswept curve. Might be worth a try/ look. Geoffrey Crawley published a modification of DK-50 for use as a one shot high sharpness developer which might also give some jumping off points for modifying the formula for greater sharpness.

If you're really determined to do something with Rodinal, Mirko at Adox/ Fotoimpex might be a useful person to ask - given that Adox now makes the official Rodinal "together with former Agfa scientists", there might be someone at Adox able to give a clear answer on the viability of making a replenishable developer that behaves like Rodinal.

Thanks. If Rodinal didn't work out, I might try a metol-glycin developer (FX2). But first, there might be a possibility of getting a pyrocat variant to work, which is much closer to the ideal. Testing ahead....

What is Mirko's contact info? Maybe a Ordinal type could be replenished if it was activated by something other than hydroxide?

-Jarin

 

[John Wiegerink]

I was going to suggest DK-50 also, but figured somebody would and they did. I have used it with very good results on ISO 100 film, but I prefer it diluted. When it is diluted it acts like a Beutler style developer, but with a little more punch. More people should try DK-50, but I guess it's just one of those lost in space developers of old. JohnW

 

[Lachlan Young]

Thanks. If Rodinal didn't work out, I might try a metol-glycin developer (FX2). But first, there might be a possibility of getting a pyrocat variant to work, which is much closer to the ideal. Testing ahead....

What is Mirko's contact info? Maybe a Ordinal type could be replenished if it was activated by something other than hydroxide?

-Jarin

Mirko posts on here as ADOX Fotoimpex - however, not sure how regularly he logs in. I suspect that an email to Fotoimpex might be the best approach - info@fotoimpex.de - they're not a massive company, so I'm sure it should get to his desk reasonably fast.

The buffering properties of metaborate seem to be very useful in terms of getting a replenished system to work - and it is worth noting that metol and p-aminophenol are very close relatives (as is glycin) - and I suspect that modifying any high acutance developer for replenishment will bring you back to something close to DK-50. The major headache I see with Pyrocat is that the compensating & sharpness enhancing properties people ascribe to it seem to relate to the effects of localised developer exhaustion - which I can only see as presenting a massive process control issue in terms of consistency over several thousand feet, or if replenished heavily enough to ensure consistent behaviour, you'll potentially lose those same localised exhaustion effects.

The other developer I've heard compared to some of the pyro developers in terms of delivering sharp, fine grain is (counterintuitively) dilute Perceptol at about 1+2 or 1+3 - I've used it a bit & it is quite nice without being mushy. More interesting however is that it can be replenished & most replenished developers once properly seasoned tend to behave not a million miles away from a 1+2 dilution used single shot - the replenisher is not currently made, but a few thousand litres will probably change minds...

 

[Mr Bill]

Unfortunately, what limits options is that a motion picture machine does not start development of all the film at the some time, but rather runs the thread of film through all the solutions, so the start of the roll is already being washed as the middle of the roll is just going into the developer. Therefore, a developer replenishment system seems to be necessary, as well as constant agitation. This system seems to preclude the possibility of a using tanning developer, which would have been my first choice by far. The oxidation products would keep accumulating.

You're right about the replenishment and agitation. Typically agitation is a combination of submerged "turbulator bars" directing a stream of pumped chemicals against the film combined with the forward motion of film through the machine. However, oxidation products, etc., shouldn't keep accumulating. They should eventually arrive at some equilibrium level in the machine, based on the replenishment rate ( the byproducts leave the tank as either "carryout" in the wet film, or as "overflow").

Not sure however how well or easily a replenished system based on this could be achieved. Rodinal would be even more challenging I think - a full scale R&D job. Big issue is dealing with developer byproducts & their effects, which is probably why most replenished developers follow fairly similar designs.

I concur.

IMO, you should really be relying on your processing lab to direct you on this, preferably using a mainstream process that they are already familiar with. You don't have enough knowledge to be calling the shots on this (unless your outfit is ready to keep throwing time and money into this). I'd suggest to tell the lab your concerns, let them advise, and do some tests based on this.

If you wanted to use your own custom developer, here's roughly how it would work. You would set aim levels for all of the chemical components in developer, including the main byproducts. Then you set a replenishment rate which is high enough to dilute processing byproducts to your aim levels. Once you know these two things, plus the average rate at which your film depletes the developing agent, then you could formulate a developer replenisher. Then you would want to do test processing along with chemical analysis of the tank solution and make any appropriate tweaks to the formulation. You would ideally do this on a small scale test bed, as you are essentially throwing away film during this process. Additionally you need a way to get your initial tank mix into the final "seasoned" condition; this is what a "starter slution" is used for, so you would essentially have to design your own starter solution. Note that I'm ignoring the sensitometric testing that should be done to make sure the results conform to what you desire. Additionally you need a way to do chemical analysis on the major chemical components.

Your processing lab would need to set aside a cine processor exclusively for your work, as well as have an independent developer replenisher supply for that machine. (In days past, no one would want to put an expensive machine like that at your disposal, but perhaps there are plenty in mothballs today?)

As a note, the way they would typically adjust process times is a combination of the machine speed and the processor rack configurations. Most likely they have a working configuration for the fixer and wash, etc., so they'd prefer to leave the machine speed alone, and just adjust spacing of rollers on the rack. It's not like you would do in your hand tank, where you just leave the developer in the tank a little longer. With the cine machine, they need to remove racks, reconfigure, restring leader and replace the rack. Then verify time in solution and run a processing test, etc. If you want to change the machine speed, this changes the "wet load" on the dryer, so you'll need to sacrifice some more film while they readjust their heaters and airflow. So you can see there is a chunk of labor, at least, in every change you want to try.

If you don't keep regular production work on the machine you may have issues with the process control, etc. The lab would deal with that, it's just more labor and chemical costs.

Anyway, the simple answer here is to rely on your lab for their expertise. If you want to second guess them, be ready to pay the costs.

 

[Gerald C Koch]

Many years ago there was an article called Rejiggered Rodinal. The concenetrate was diluted 1+24 with 9% sodium sulfite. The working solutuion was replenished with FS Rodinal with 1 ml per roll of film. The working solution as discarded after 1 month.