Always consider MDS's (as apparently they are now known) in context.
I doubt that you'd be willing to drink it or wash your face with it. More importantly, I do not think that blanket statements like "fixer is not hazardous" are helpful --- at least Matt's version ("I wouldn't even call it hazardous") conveys that this is his personal judgement call, as is his comparison to household products.
Can we agree that being "properly informed" would include reading the MSDS? Below I have copied a portion of the MSDS of one commercial fixer. You are of course free to ignore what it says, but please don't ding me for using the terminology or precautions that are more or less in line with the MSDS.
Air Force tech orders in the 70s called for gloves, the old fashion rubber gloves when mixing chemistry use of tongs when printing. The only time I used my hands in a tray for developer, stop bath, and fix was when we would batch process up to a 100 prints at a time, same print. I would process 10 to 15 prints at time, shuffling the prints in the soups from tray to next when a hard wash up before the next batch
There was a Photrio thread about safety of metol a while back - link.It's ideal if you are insensitive to the likes of metol and will never get dermatitis but how can anyone know in advance if they are sensitive or insensitive without taking the risk that they might be? I presume that if you have guessed wrongly and do use your bare hands then notice the beginnings of a problem so stop using bare hands immediately then the dermatitis clears up completely and no long term harm done?
If that is the case then it might be a reasonable course of action to try bare hands until a problem arises
pentaxuser
Looking again at the prints (below), they don't really look like bubbles, but more like liquid drops of non-development.
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View attachment 401713
I would agree with snusmumriken's reply, as it happens to me occasionally and I still don't quite know how it happens. I believe some how, most likely fixer, gets onto the paper before it is put into the developer and this stops, usually small, areas from developing.Those larger blemishes: looks to me like you’ve splashed stop bath or something onto the print before development. Go gently with the rocking!
You would find much the same level of warning for common household cleaning products. Here is the one for Clorox bleach:
Do we avoid coming into contact with Clorox or abandon its use entirely? Of course not. We just use it carefully.
As soon as I get into volume, I make mistakes.
This is when after a dozen prints my fixer is exhausted my developer stinks and my stop bath is purple.
Indicator stop bath is cheap and it’s so satisfying to replace it mid-session.
But I make too many fixer mistakes. I lately have been focusing my attention on two-bath fix where the first tray goes to discard and the second tray gies to jug. But only for a couple weeks. After that I will mix fresh
From the msds for water:
More relevant, the from the msds of ammonium thiosulfate:
...
Strange that there's no real toxicological data on the primary component of rapid fixer.
and yes, my selections do lean slightly on the side of caution.
But I would be grateful if you did not suggest, as you might have done in post #66, that I am uninformed about the safety of the chemicals I use.
But I would be grateful if you did not suggest, as you might have done in post #66, that I am uninformed about the safety of the chemicals I use.
There is a subset of information surrounding this issue that you are less informed about - or at least less experienced with: it is how dealing with the information in an MDS is affected by the actual use of what is in the bottles and bags of the stuff you buy.
The msds you cite is for Kodak rapid fixer. I use a different rapid fixer - one that uses different ingredients (same main ingredient).
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The hazardous materials are vinegar, lye, borax, and disodium disulphite - all in much lower quantities than the ammonium thiosulfate (which we know they haven't bothered to test).
What happens when you mix vinegar with borax and lye?
Furthermore, you can make a fixer from just sodium thiosulfate in water. Not toxic. Not hazardous.
The MSDS for sodium chloride doesn't claim that it has the combined harms of sodium and chlorine.
I found an msds for water, it included the usual information
- Melting point/freezing pointMelting point/range: 0 °C
- Initial boiling point and boiling range100 °C
- Relative density1,000 g/mL at 25 °C
I missed this thread on the first go around.
Back when I was making enlargements (now contact printing argyrotypes) I was using pin registered sharp and unsharp masking techniques which made it impossible to finish a print in one printing session. Most prints took multiple days to make a sequence of masks which worked, so I came up with a developer and methods to pick up *exactly* where I left off...days, or even weeks later...with the same batch of developer working solution.
EDIT: Also used a compensating metronome timer for consistent enlargement exposures.
Wrote about it here: https://www.photrio.com/forum/resources/12-15-developer.123/
They have changed them now, I think. They used to be mylar with an easily removed spigot...perfect for air & light tight storage.I’m interested in the idea that boxed wine comes in between sessions. That sounds very well organised.
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