Darkroom ventilation query

[tribal-warrior]

I'm planning to set up a temporary darkroom in a small section of my bedroom. Something that I can set up to develop prints from a pinhole camera and then take down and dismantle. I would likely set the darkroom up every now and then (whenever I have a few prints to make.) I might do some contact printing as well later on (without an enlarger.)

I would really like to mimimise the use of chemicals in this bedroom darkroom. For developer, I'm going to use one of the cafenol / instant coffee alternatives with Vitamin C etc. And for stop bath, I'll use water and lemon juice. As much as I'd like to use a more environmentally friendly substitute for fixer, it seems I can't. There is discussion online about using salt water for fixing though others say that it doesn't work that well. And I'm not keen on letting my prints sit in there for 48 hours etc. So fixer would be the only commercially available darkroom chemical that I would be using.

With regards to ventilation, I'm wondering if I could do without an exhaust fan? This bedroom has decent sized windows that are a bit over a meter high and they will be open. Though they will be about 2.5 - 3 meters away from one of the 'walls' of the darkroom. The darkroom 'walls' and 'roof' will consist of large black table cloths. I'll have a mini maze at the entrance to the darkroom like an 'S' or 'U' shape which should hopefully help with air flow. And the fixer would be positioned very close to the mini maze. I could stick my head in the maze every now and then when I'm at the fixer. By the way, the darkroom 'roof' would not be very high and I doubt that I would be able to stand up fully inside. I may have to crawl through the maze to get in and out.

There is a ceiling fan in this bedroom that will be turned on when the darkroom is in use. And that should blow at least some of the air into the maze. Though as the maze will be 'U' or 'S' shape, light won't get in obviously but air will....but would be slowed down somewhat. I also don't plan to have very long darkroom sessions. I doubt that I would be in there for hours.

Suppose that the ventilation may possibly be adequate during darkroom use......would there be any issues after the whole thing is packed away? The fixer and makeshift cafenol developer and vinegar stop bath, trays etc would be removed from the bedroom and stored in another room. Though would any fumes from the fixer still be present in the bedroom after it has been used and removed? Would the ceiling fan and open windows help to dissipate any remaining fumes?

 

[tribal-warrior]

Actually, I wonder if I should rearrange the order of trays. With my original plan, I would have the fixer and wash bath near the maze. And the cafenol developer at the other end. Though if I happened to be near the cafenol developer and stop bath, I guess the fan generated air coming through the maze would blow the fixer fumes towards me? So perhaps it might be better to have the fixer and wash bath at the other end instead and the cafenol developer near the maze.

It would be great if I could have a second maze at the other end for even greater air flow but that is very elaborate and I may not have enough space for that. Or perhaps I could make a smaller version of a secondary maze specifically for air movement...not large enough for human movement.

 

[tribal-warrior]

I did think of an alternative and this involves having no fixer in the darkroom at all. Suppose after the stop bath, I dump the prints in a heavy salt solution with water and leave them in there in the salty water overnight. That may partly fix them perhaps. Then in the morning, take the prints outside and place them in fixer outdoors. I know this sounds like a very unorthodox method. Obviously, I would try to keep any kids and animals away from the fixer in an outdoor environment. And put down a 'drop sheet' (used for painting) to counter accidental spilling. Or place the fixer tray inside an extra large tub.

 

[tribal-warrior]

Ive just come across someone using an odourless fixer in another forum. Not many details were given but apparently, it's more expensive than regular fixer. Perhaps that could be another option.

 

[tribal-warrior]

I did a bit of reading about the odourless fixer, Apparently, it's good for darkrooms that have little or no ventilation. That does make it very attractive to me.

I discovered another interesting fixer option that is in tablet form - TETENAL Superfix tabs. It has no boron compounds which makes it relatively 'safe.' I actually wonder which of these two fixers would be the safest / least toxic. I also wonder if they would both be compatible with home made developer and stop bath using common household products.

 

[Epstar83]

For the room you describing and the chemicals you're using I think window ventilation should be absolutely fine, maybe with a small fan to keep air moving a little. I've only developed film with Caffenol and environmentally friendly as it may be... it does not smell great. Lol

Best of luck with the new darkroom!

 

[jmav]

Honestly, you're overthinking this. Just using regular chemicals and opening a window after you're done would be absolutely fine. Also, why do you need a darkroom if you don't want to use an enlarger? Just use a jobo print drum if you want to develop prints from a pinhole camera. That way you can do all of the chemical handling in a well ventilated area with plenty of light.

 

[tribal-warrior]

For the room you describing and the chemicals you're using I think window ventilation should be absolutely fine, maybe with a small fan to keep air moving a little. I've only developed film with Caffenol and environmentally friendly as it may be... it does not smell great. Lol

Best of luck with the new darkroom!

Gosh, thanks for warning me about the strong smell of Caffenol. I had the wrong impression that it had a pleasant smell!

 

[tribal-warrior]

Also, why do you need a darkroom if you don't want to use an enlarger? Just use a jobo print drum if you want to develop prints from a pinhole camera. That way you can do all of the chemical handling in a well ventilated area with plenty of light.

Oh, I wasn't familiar with the Jobo print drum. Interesting idea.

Though like I mentioned above, I would be keen on doing contact printing at some point (with or without an enlarger.) So the paper would be out in the open for that (hence the need for a darkroom.)

 

[Shashin]

Acetic acid is what stop bath is. Acetic acid is the main component of vinegar. Yes, it has a pungent small and in extreme concentrations can be nasty. But you should be using diluted solutions of that. Stop bath is used to stop development. Developers work because they are alkaline. The stop bath simply changes the pH of the alkaline developer to acid. I would not be concerned about stop baths.

If you want to limit the fumes from developing with trays, you can place a sheet of plastic or acrylic over the trays, lifting the cover to insert of remove the paper.

Mixing darkroom chemicals can be the nastiest part of the process, but you can use a respiratory masks like an n95 when you do that. You can also do that outdoors.

Photographic chemistry has been used by amateurs for over a hundred years. I think you are overestimating the risks. You just need a few simple precautions.

 

[Epstar83]

Gosh, thanks for warning me about the strong smell of Caffenol. I had the wrong impression that it had a pleasant smell!

Yeah, it's eco friendly but doesn't smell great.

 

[tribal-warrior]

I would not be concerned about stop baths.

I'm not sure why you think I'm concerned about stop baths. Especially considering that I'll be using a mix of water and lemon juice for my stop bath.

 

[Shashin]

I'm not sure why you think I'm concerned about stop baths. Especially considering that I'll be using a mix of water and lemon juice for my stop bath.

Well, you seem to be using substitutes for your chemistry. All your emulsions are suspended in a gelatin base and your lemon juice will contaminate that. Acetic acid is a simpler solution.

 

[tribal-warrior]

Well, you seem to be using substitutes for your chemistry. All your emulsions are suspended in a gelatin base and your lemon juice will contaminate that. Acetic acid is a simpler solution.

For the odorless fixer, it's recommended to use the odorless stop bath in combination with it. And I note that the odorless stop bath contains citric acid. So for a home brew alternative, I thought that maybe lemon juice might work okay (since that obviously contains citric acid.) There's also a youtube video that recommends using lemon juice mixed with water for a stop bath with photographic paper.

Maybe I'll use vinegar and water instead.