B/W paper developer for roller transport processing

Hello good people of Photrio.

I recently bought a Thermaphot ACP 252 which has two available processing times (32 sec or 45 sec) a temperature range from 28 to 45 °C.

It works really well for doing color prints since a lot of RA4 developers are designed for 35 °C, 45 sec.

However, I'd like to also do B/W with it at some point and have been looking for paper developers that work within these parameters but am having difficulty finding any. For example, the Ilford 2000 RT developer datasheet calls for 25 °C at 32 sec, which is 3 °C lower than the minimum temperature my unit can maintain.

Does anyone know whether it could still work somehow despite this 3 °C difference. If not, does anyone know of an available & suitable developer?

Kodak used to offer a liquid-concentrate paper developer called "Polymax RT" that was meant for this purpose. We used it in a Kodak "Polymax" 20" wide roller-transport processor (it was made by Hope). But that was almost 15 years ago, and I don't know if Kodak still offers it; might be worth a search though.

I ran B&W RC paper through my Durst Printo using Freestyle’s Dektol clone at about 28C, 45 sec. It worked. Try it and see if it works for you.

fleblebluble said:

Does anyone know whether it could still work somehow despite this 3 °C difference.

Click to expand...

Of course it will. You may have to replenish it at a slightly higher rate, but it'll surely work. If you notice any fogging (which I really doubt), add a little benzotriazole until there's no more fog.

MarkS said:

Kodak used to offer a liquid-concentrate paper developer called "Polymax RT" that was meant for this purpose. We used it in a Kodak "Polymax" 20" wide roller-transport processor (it was made by Hope). But that was almost 15 years ago, and I don't know if Kodak still offers it; might be worth a search though.

Click to expand...

Yes Kodak Polymax RT developer is still available.
I use it in my ( modified ) Ilford 2150RC processor. It's an excellent quality developer which requires no starter.
Dev time in my machine is 17" ( at 37*C ) and used along with Ilford Rapid Fixer.
Total dry-to-dry is 70".

Listed on UK seller Dupli's website .... https://dupli.co.uk/kodak-polymax-rt-dev---rep-to-make-2-x-25l


Highly recommended !
John S

Please see the Harman Tech sheet for 2000RT, it says:
2000RT developer and fixer...can be used in the temperature range of 20–40ºC (68–104ºF).
Suggested dev times

Temp Secs
20/68 46
25/77 32
30/86 22
35/95 15
40/104 12

Regards,
David

Thanks everyone for the replies! I'll try to find a supplier of Ilford 2000rt or the Freestyle Dektol clone that will ship to Iceland.

I have a Durst Printo, which holds 2.5 litres per bath, so I'm assuming your Thermaphot has a similar bath size.

In effect, you can use pretty much any of the popular B&W paper developers and get close to their suggested development times at various temperatures. I certainly had been doing that for around 10 years when I switched to my own from raw chemistry, E72 which is supposed to be a more environmentally friendly developer. The Printo machine can work at lower temperatures, but I always used temperatures around 31-32ºC at 45 seconds and always had excellent results. I've almost exclusively used Ilford RC papers with this method as well as Kentmere RC papers.

My E72 formula is easy to do, although I do acknowledge the issues you may have getting some ingredients in Iceland having visited the place for almost two months pre-covid.

E72 at 1:1 gives brilliant results with Ilford MGIV paper I haven't used the latest, but that will come shortly when my MGIV runs out.

1:1 gives high contrast, 1:2 or 1:3 for lower contrast.

I mix 1.25 litres of stock solution and mix it immediately with water for a high contrast 2.5 litre 1:1 working solution. Depending upon your subject matter and how much development is required, you should be good for 30 20cmx25cm (8x10") prints with around 40 prints possible before the edge of the developer goes off. This is using no replenishment.

750ml water around 50ºC
Phenidone 0.3g
Sodium Sulphite Anhydrous 45.0g
Ascorbic Acid (Vitamin C from a chemist) 19.0g
Sodium Carbonate Anhydrous 77.0g
Potassium Bromide 1.9g
water to 1 litre

Once I used 35ºC as I had used RA4 printing in the last use, no difference to speak of.

Using fresh developer if you are finding low contrast, or the blacks aren't really black, up the temperature; I'm fairly certain you'll then get nice black blacks. Temperature variance is the way you control development, as you cannot (easily) change speed.

Mick Fagan said:

I have a Durst Printo

Click to expand...

Those are really nice. I've got one sitting next to my desk at the moment; it's a beautiful machine and far superior in construction to the older Thermaphot units (including the "Durst" RCP series) with their rubber rollers. It's also nice that it's a modular system that you can configure for each session the way you need it. The only qualm I have with it is that the units don't stack nicely, but it's a minor issue. Hang on to that machine.

koraks said:

Those are really nice. I've got one sitting next to my desk at the moment; it's a beautiful machine and far superior in construction to the older Thermaphot units (including the "Durst" RCP series) with their rubber rollers. It's also nice that it's a modular system that you can configure for each session the way you need it. The only qualm I have with it is that the units don't stack nicely, but it's a minor issue. Hang on to that machine.

Click to expand...

I certainly will hang on to it. I purchased it new on the 23/02/1993, so I've had it for 30 years and six months.

It was used for RA4 at least twice a week for around 10 years. Then I started to do B&W prints after a request by a friend for some multiple prints from single negatives and usage upped quite a bit, often 20 or 30 prints from a negative; this endured on and off for around 7 years until my retirement 11 years ago.

So far nothing has broken; quite a robust machine.

Keeping tar off the rollers is another issue though.

Mick Fagan said:

I certainly will hang on to it. I purchased it new on the 23/02/1993, so I've had it for 30 years and six months.

It was used for RA4 at least twice a week for around 10 years. Then I started to do B&W prints after a request by a friend for some multiple prints from single negatives and usage upped quite a bit, often 20 or 30 prints from a negative; this endured on and off for around 7 years until my retirement 11 years ago.

So far nothing has broken; quite a robust machine.

Keeping tar off the rollers is another issue though.

Click to expand...

do you know where I might find some exit rollers, I too bought my in the 90's and put thousands of bw through it. I have not used it in maybe 2 decades but want to fire it up and when I stopped using it there were 2 exit rollers that got gummed up... thanks

Sorry, can’t help with the exit rollers- but are they beyond repair? I got a Printo machine that probably sat for 20 years with the exit rollers stuck to each other and dried chemistry mucking up the works. I was able to carefully separate the rollers and clean up the machine which now works fine. My only other suggestion would be to keep an alert up on eBay. Modules do sometimes come up for sale. Best of luck!