Rollei Vintage Classic Dev or non-hydroquinone dev
While placing an order for the next batch of supplies I found the above developer which stated that it was non-toxic as it doesn't contain hydroquinone. Is anyone familiar with the Rollei Classic (print developer), I wonder what about the formula makes it vintage or classic, and what is the purpose of hydroquinone? I noticed that all the other print devs. contain it. I found another quick reference about in that doesn't serve a purpose in the development rather in the "keeping" of the developer. Anyone know anything about this? Thanks kindly, if this has been addressed (I did look for other threads before posting) kindly point me in the right direction. Hopefully this isn't too noob, still learning :-)
It could mean that ascorbic acid is used in place of hydroquinone as a regenerator of another developer such as Phenidone or Metol. That would make it less toxic, but not completely non-toxic. Some are allergic to Metol, for whom it causes a skin rash. A combination of Phenidone and an ascorbate would be my guess. I'm confused about the "Rollei Vintage Classic" title, though I guess it could have been concocted about 30 years ago. The term "Vintage" doesn't mean much unless it refers to the year the wine was made. Old developer is not usually all that great, although old Rodinal is often as good as when it was made.
Hydroquinone is generally the high-contrast developing agent, it has superadditivitity with phenidone and metol which make it great for use with them. Do you have a specific allergy to something in developers? Photographers have been using standard developers for many years and are probably exposed to them much more often than most of us in our home darkrooms.
Going back to basics, there are four developing agents that are potentially interesting in this context:
- metol (M)
- phenidone (P)
- hydroquinone (Q)
- sodium ascorbate or ascorbic acid (C)
Note that there are variant names (Elon for metol, for instance) and chemical variants (such as Dimezone S for phenidone) for many of these. Sometimes mix-it-yourself formulas need to be adjusted for some changes.
Many common developers, for both film and paper, are metol/hydroquinone (MQ) formulations. Metol is said to be "superadditive" with hydroquinone, meaning that the two work together more powerfully than either one works alone. Other superadditive combinations include PQ, MC, and PC. PQ combinations are somewhat popular. A few PC developers exist -- most notably among commercial products, XTOL, Agfa Neutol Plus (but not others in the Agfa Neutol line) and Silvergrain Tektol. XTOL is intended for film, but Neutol Plus and Tektol are paper developers. I don't know of any commercial MC developers, although I have seen (and use one) MC mix-it-yourself formula (DS-12). It's common to see two, and sometimes three, developing agents in a developer both because of superadditivity and because using two agents enables the developer to acquire the best characteristics of each agent.
Generally speaking, metol has minor health risks because people sometimes develop a sensitivity to the chemical, resulting in rashes when they come in contact with it. Various sources indicate that hydroquinone is the most damaging of these four chemicals to the environment, and may be a little more toxic to humans than the others. Phenidone and its variants seem relatively benign by comparison, at least in the quantities used. (Developers typically contain only about 1/10 as much phenidone as they would metol.) Ascorbic acid is also known as vitamin C, so it's not really a health threat. Thus, from a health and environmental safety perspective, PC developers are best. This isn't to say that MQ developers are on the level of, say, equal masses of plutonium or anything; but if you want to minimize risks, it makes sense to use a PC developer, or at least a PQ developer, rather than an MQ developer.
I'm unfamiliar with the Rollei developer to which you refer, gonzo74, so I can't comment on its composition. My own print developer of choice is DS-14, which is the mix-it-yourself predecessor to the commercial Silvergrain Tektol. These are both PC developers and they work just fine for me. They produce results that are indistinguishable from those of Kodak Dektol, at least with the variable contrast resin-coated papers I generally use. (Some papers respond more strongly to changes in developers than others, though, so there might be differences in other developers.)
One other comment: The four developing agents I just described aren't the only ones; para-aminophenol, catechol, glycin, and others can all do the trick, and may be preferable for one purpose or another, either alone or in combination with other developing agents.
Hi SRS, Ben and Gainer, Thanks for your help. I went and dug around the Rollei page and found that this particular developer is "baugleich" with Agfa Neutol Plus, meaning it is formulated to the specifications of Neutol Plus. I did a little more digging around and found this list on photonet (to give credit where credit it due, the link: http://photo.net/black-and-white-pho...g-forum/00HMuI)
From several MSDSs I have complied the following list of ingredients incl (CAS numbers):
Trisodium Nitrilotriacetate (5064-31-3) Less than 1 %
Potassium Sulfite (10117-38-1) 1- 5 %
Potassium Carbonate (584-08-7) 10-20 %
Diethylene Glycol (111-46-6) 1-5 %
Iscascorbicacid (sic) sodium salt (7378-23-6) 1-5 %
Sodium isoascorbate (6381-77-7) l-5 %
Potassium Bromide (7758-02-3) 1-5 %
Potassium metabisulfite (16731-55-8) l-5 %
Water (7732-18-5) 55-60 %
pH .......................: 10.8 SPECIFIC GRAVITY .........: 1.241 at 68 F (20 C)
It looks like it is an ascorbic acid developer, the Ilford Multigrade that I've used is a dimezone-s/hydroquinone developer, I've read that dimezone-s is similar to that of phenidone, (please correct me if I am mistaken). It isn't that I have developed allergies to one or the other, I was hoping to reduce the amount of toxic stuff I have in the darkroom, I'm also quite realistic in this sense as well, we are after all handling chemicals; we can go so far with that idea. My thinking is if there are less toxic choices out there then it might be worth to try it as well. I always go for the Ilford stuff because it doesn't stink as much as the others :-) It is interesting to learn about this stuff, but I really have a long way to go...
Last edited by gonzo74; 03-24-2009 at 06:11 AM. Click to view previous post history.
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Yes, Dimezone S is a phenidone variant. Dimezone S tends to last longer in solution, so most commercial developers that use one of these use Dimezone S. Phenidone seems to be a bit easier to find for hobbyist formulas, though. Incidentally, phenidone/Dimezone S are used in such small quantities that they're often omitted from ingredient lists. My hunch is that this is true of the ingredient list you posted above; it's probably actually a PC developer.
I was surprised to learn that it is the same formula as the Agfa Neutol Plus, I thought that stuff was still being made or at least I have seen it around. In any case, I'm pretty interested to know what it does, so I think an experiment is in order. Thanks again for your quite knowledgeable help, most appreciated. This place is such a great resource!
I've never used Neutol Plus myself, although I was on the verge of trying it when I instead decided to start pursuing home-brew developers, and started with DS-14. From what I've heard, though, Neutol Plus is a perfectly good general-purpose print developer. I've seen a report or two that it can go bad suddenly, but this isn't catastrophic in a print developer (as opposed to in a film developer).
Well I think that it is always worth a try. I'm not at the point that I can start playing with home-brew developers. Although I envy those that can! Imagine the ability to tweak a formula exactly to one's liking :-) Once I've had the chance to try it, I'll post some results or comments. Thanks again. Also isn't Agfa Neutol Plus still being produced? I thought I saw it somewhere online...