MCM 100 film developer

[Ian Grant]

The mistake was probably mine as a PPD dev needs to be "aged" with some dead, exposed film run thru it. I only ran one dead roll thru it and it may never have peaked, so therefore, it probably didn't work well.

Never heard that about PPD devs only those that are replenished like Edwal 12 but not ones like MCM-100 and Merotol-Metol.

I used a lot of Meritol based developers while at school and had no problems, Johnson's certainly never suggested ageing their developers.

Ian

[jim appleyard]

I'll have to dig into my texts to find out where I got that info from.

[Ian Grant]

I'll have to dig into my texts to find out where I got that info from.

I don't think you're wrong Jim, I know that DF Cardwell and others have recently found this is definitely true with Edwal 12.

From experience I know that developers like D76/ID-11, Microphen/ID-68, Adox Borax MQ all give far better results when seasoned and used on a replenishment basis. In commercial darkrooms ID-11/D76 wouldn't be used fresh without topping up with some of the previous batch first and would still take a few days/films to reach it's peak.

So it would be interesting to know what other PPD developers work best this way.

Ian

[Ian Grant]

http://www.photomemorabilia.co.uk/Jo...Chemicals.html
Meritol-Metol looks interesting.

The 1960 BJP Almanac gives the formulae for Meritol-Metol and Superfine Grain (also known as Meritol0Sulphite). Note the slight difference in the amount ofMeritol in Meritol-Metol.

Meritol-Metol

Meritol 13.7 g
Metol 2.3 g
Sodium Sulphite (anhyd) 90 gms
Water to 1 litre

13.7 gms Meritol = 6 gms PPD + 7.7 Pyrocatechin


Superfine Grain (Meritol-Sulphite)

Meritol 16 g
Sodium Sulphite (anhyd) 90 gms
Water to 1 litre

16 gms Meritol = 7 gms PPD + 9 Pyrocatechin

There's a warning that Superfine Grain developer might give dichroic fog with faster emulsions.

Ian

[jim appleyard]

By golly, I knew I saw this somewhere! Read Fred De Van's post near the end of the thread where he mentions "running a load of inconsequential film". http://photo.net/black-and-white-pho...g-forum/0065dl

There's also a mention by Conrad Hoffman in another post. I'll try to get a link. Yup, 1st paragraph.
http://photo.net/black-and-white-pho...g-forum/007JMl

This may be why my MCM100 didn't work well for me. Perhaps I didn't season it enough. It was also a homebrew and there's a better-than-good chance that human error was introduced in mixing. The OP may do very well with the kit from formulary.

[Ian Grant]

Thanks Jim, that makes sense as it's referring to Edwal 20 in the first link.

Ian

[jim appleyard]

There's also a section on ripening in A&T (or should it be T&A? . It's a blanket statement re: all PPD devs; running a dead roll thru it to ripen.