The new long-life paper developer

Moersch Photocheme introduced the ECO 4812 developer a few months ago, which was described by the master himself [Wolfgang Moersch I assume] as “the best developer in the world." This came just at the very time that I wanted, for personal reasons, to change my chemical supplier.

I process RC paper by machine and fiber-base paper by hand in trays. An all-around developer, which gave the best performance in both cases, had not been so easy to find. The new Moersch developer, therefore, came at just the right time. Most important for me was the new developer’s suitability to machine processing. The main parameters there are the life of the tank contents, the developing time for RC papers and the replenishing.

Much has been written already about tray processing, which I agree with. My first tray full of developer is now over four weeks old and still develops my Forte fiber-base papers with no problems at 20°C and a 1+12 dilution.

I can confirm Mr. Moersch’s recommended times for different papers for tray processing; the life of the solutions is likewise excellent.

My processor is a Colenta Imageline. This has a feed width of 50cm and tanks that hold six liters each.

The developer was used in a 1+5 dilution with the addition of a starter. One liter of concentrate, therefore, was sufficient for a complete tankful for my machine. Additionally, I used five liters of replenisher, which was likewise diluted 1+5. Development was at 34°C between 30 and 35 seconds. Agfa MCP and Ilford MGIV both reached a density of about 2.1 in this time. An additional selenium toning increased the Dmax to 2.2. Very good! For enlarging and measuring I rely on my Splitgrade. For the above-mentioned papers, the parameters given by the Splitgrade were hardly influenced at all. Only a 0.4-second increase in the exposure time for MGIV.

After the first three of four weeks of use, I changed from Agfa MCP to Kentmere (in the Tetanal packaging). At first, the blacks were not as dense as with the the Agfa and Ilford papers when judged by eye. The densitometer reading showed the highest DMax to be 1.92. At first, I thought the developer was exhausted. Disappointed, I was about to replace it with new when I read on the Moersch website that Kentmere papers require a stronger dilution or more development time.

I changed the time on my Colenta to 35-40 seconds and kept everything else the same. Lo and behold, I achieved a DMax of 2.06 from then on. I got some Agfa MCP paper and measured a DMax of 2.1 at a deveopment time of 30-35 seconds. Great. So, the chemistry was not exhausted!

Currently, the developer has been in continuous use in the maching for nine months. Only with Kentmere paper do I increase the development time. The replenishment is approx. 250ml per square meter of paper run through the maching.

My first experience with Moersch ECO 4812 has been very positive. I now just use one deveoper. If the different times between Tetenal/Kentmere RC papers are observed, the lab worker has a very economical developer that delivers first-class results.

A few words about the desired image tone: Both Agfa MCP and Ilford MGIV in the glossy finish take on a pleasant, slightly-warm tone from the machine processing. The matt version of both papers are somewhat more neutral in tone. I only tray process Foma papers, since the emulsion is supposedly not hardened and relatively thick. It sticks and collects dirt in the machine.