EDTA worth putting in ID-78?

[john_s]

Since Agfa Neutol-WA was discontinued, I've been mixing my own ID-78, a standard Ilford warm tone PQ paper developer. Since the MSDS for Neutol-WA contains EDTA TetraSodiumSalt I've been adding some to the Ilford formula. When I do this, the colour of the developer changes from very pale pink to colourless.
The developer works well, lasts well and I'm happy with it.

I have read that the EDTA is used to prevent calcium scum when the water is hard. My local water has extremely little calcium, so is it a waste to use EDTA?

Ryuji Suzuki, writing about Kodak Hypo Clear said that adding the minor components (sodium citrate and EDTA-4Na) would slow the deterioration that afflicts HCA. Does anyone know if using those ingredients does actually make it last longer? And might EDTA improve the lasting qualities of ID-78 (already quite good)?

 

[Mick Fagan]

I have used ID78 as a Neutol-WA replacement on and off for some years. I have never used EDTA, nor seen the need for it and I'm on the same water supply as yourself. Melbourne's water does have some issues, usually around March after a long hot dry summer. The various reservoirs may have a flocculent added to the water around that time in order to drop precipitates to the bottom of the reservoir if they are running low. Even then the Melbourne water is pretty good.

I haven't noticed much if any difference over the 2019 - 2020 years after the drought then bushfires, followed by the floods. The input of de-salinated water in ever greater amounts over the entire reservoir system during that really dry period also didn't seem to make any difference, but this is only going on print output, not scientific measurements. This year the water seems really good, which, when one considers the amount of rain we've been having, is pretty good.

I generally mix 2.5 litres and use my Durst Printo processor so I have super consistent temperature control, which is another parameter taken care of. I run the bath at 25ºC for completion of development certainty in 45 seconds. I generally dilute to 1:1 for higher contrast, although there is some loss of warm tone strength at this dilution, it suits me.

 

[Nicholas Lindan]

I add a pinch of EDTA when making D-76, D-72 & HCA. Without it I sometimes get some calcium precipitate. I don't bother with it if I am mixing using distilled water. I doubt very much that EDTA will prolong the life of a developer, but strange things do happen...

 

[Ernst-Jan]

Since Agfa Neutol-WA was discontinued,

It is still for sale, at least in Europe. Adox Neutol WA
https://www.adox.de/Photo/chemistry/paper-developers/adotol-liquid-wa-2/

 

[john_s]

It is still for sale, at least in Europe. Adox Neutol WA
https://www.adox.de/Photo/chemistry/paper-developers/adotol-liquid-wa-2/

Thanks. Here at The End of the Earth (not quite, New Zealand is further) it is available intermittently but I'd rather stick with something that I know I can always get and that won't be discontinued.

 

[john_s]

Thanks to all for the feedback. For my next batch, I will use a tiny amount "just in case." I wonder why the addition of EDTA makes the slightly pink colour of the developer vanish. It's a long time since I mixed Xtol, but if I remember correctly that happens when Part_B is added to the dissolved Part_A. I assumed that it was the change in pH.