Immersion Heater

[cliveh]

IIRC, hydroquinone is much less active at 15C than metol, so working at 15 C with Dektol, which includes both, will give you different (lower contrast) results than if you work at 20C.

But you can correct that with dev dilution or filtration. Preferably the former. I would also differ with your statement of much less active.

 

[Doc W]

OP needs to keep in mind that the typical sous vide has a minimum water line...the anova in the link is 2.56", and its range of control is 32˚-197˚F...darkroom range is covered.

Most less expensive units only go down to about 77F

I realize that a good one can have very fine control. I just can't figure out how to adapt it physically to what I am doing, i.e., using a relatively shallow tray as a water jacket for a tray of developer. Any suggestions?

 

[MattKing]

I would also differ with your statement of much less active.

Perhaps I should have said that a decrease to 15C has a much greater affect on activity with hydroquinone than it does with metol.
Thus affecting the way that Dektol performs.

 

[wiltw]

I realize that a good one can have very fine control. I just can't figure out how to adapt it physically to what I am doing, i.e., using a relatively shallow tray as a water jacket for a tray of developer. Any suggestions?

No suggestion...but that is why I raised the issue of minimum water line as a consideration, as well as min temp. Clamp height figures into things, too...most cooking is not done in really shallow vessel.

 

[AgX]

The advantage of the sous-vie heaters is their impeller, disadvantage is their mounting .

Thus remains the (cheaper) immersed thermosthatic 25W aquarium heater.

 

[Doc W]

But you can correct that with dev dilution or filtration. Preferably the former. I would also differ with your statement of much less active.

Clive, for me, the main point is that if I can get the developer working at 20C, I won't have to "correct" with dilution or filtration. It is simply one less thing to worry about.

But suit yourself. I am not arguing that there is only one way to skin this cat. I am just looking for a method that reduces the variables so I can concentrate on other things. Before I got my Jobo, keeping negative developer at the proper temperature was a bit of wrestling match in that miserable basement of mine. Now I put the neg in the Jobo and sip a glass of wine.

 

[mshchem]

Cinestill sells a purpose made immersion heater for $100. I have one and love it.

https://cinestillfilm.com/products/...emistry-and-precision-film-processing-at-home

These do look great. I, like Sirius Glass, have a Jobo, however, something like the Cinestill machine would be very useful for pre-heating solutions for black and white, toning, color etc. Looks like the bottle holder takes Jobo/Ilford style plastic bottles.
I need to budget for one of these.

 

[cliveh]

Clive, for me, the main point is that if I can get the developer working at 20C, I won't have to "correct" with dilution or filtration. It is simply one less thing to worry about.

But suit yourself. I am not arguing that there is only one way to skin this cat. I am just looking for a method that reduces the variables so I can concentrate on other things. Before I got my Jobo, keeping negative developer at the proper temperature was a bit of wrestling match in that miserable basement of mine. Now I put the neg in the Jobo and sip a glass of wine.

I thought this thread was about print development, not negative development?

 

[mshchem]

Lots of good feedback here. Thanks guys.

The heated pad under the tray would probably work but I am a little nervous about safety issues. Some of the ones I have seen online note that they are not totally waterproof and that makes me a little nervous.

The sou vide technique would work great for holding chemistry at a specific temperature but they are very …. vertical! I would prefer something lying down in the tray

The Jobo is also a good idea for temperature control and I have both an older CPE-2 and a more recent CPP2. I love these machines but they would complicated the printing process. I want to continue printing with trays. Having to load and empty the Jobo just for a print would be a pain.

I am leaning toward the aquarium heater with thermostat control. There are a lot of aquarium heaters that hold the temperature but only after you figure it out first. By that I mean, you have to put a separate thermometer in the water and adjust the heater until the water stabilizes at the temp you want. I need something with a built-in thermometer that I can set to a specific temp and then leave it alone. The heater would bring the water up to 20C and keep it there without my intervention. The temp in my darkroom can drift quite a bit so I need a device that can respond to the changes.

I will probably get such an aquarium heater in the near future and experiment with it in a water jacket .i.e, a developer tray placed in a larger tray. I will let you guys know the results.

I used aquarium heaters for Cibachrome, they worked fine. At that time nice German made 115V models were available. Verticallity is an issue with these as well.

 

[mshchem]

 

[AgX]

View attachment 295332

I see a what looks like a temperature probe, but got no idea how this photo is related to our topic.

 

[cliveh]

Perhaps I should have said that a decrease to 15C has a much greater affect on activity with hydroquinone than it does with metol.
Thus affecting the way that Dektol performs.

Who mentioned we were using DeKtol?

 

[AgX]

At that time nice German made 115V models were available. Verticallity is an issue with these as well.

The german ones I linked to need a min. water level, but have got no max. water level. Thus can be completely submerged, thus placed horizontally too.

However the manufacturer warns agains gripping into the aquarium when the heater is still connected to the mains. But I assume one has a low-current RCD-switch in ones darkroom anyway, as fail safe if the sealing of the heater should fail.

 

[MattKing]

Who mentioned we were using DeKtol?

We didn't specify any particular developer, but were instead discussing whether lower temperatures can create problems under some circumstances.
So if you prefer: "Thus affecting the way that Dektol, as an example, performs."

 

[Doc W]

I thought this thread was about print development, not negative development?

I was just pointing out how the Jobo solved the problem of temperature with regard to negative development in a cold darkroom with temperature swings. I don't know what your darkroom is like but mine can be a huge pain in the arse when it comes to temperature and consistent results. I am hoping that keeping the print developer at a constant temperature will also free me up a little more.

In the long run (if I in fact have that much time on this earth), I will get proper insulation and climate control, like a normal person!

 

[cliveh]

We didn't specify any particular developer, but were instead discussing whether lower temperatures can create problems under some circumstances.
So if you prefer: "Thus affecting the way that Dektol, as an example, performs."

But what about the other multitude of print developers? It just goes to show that unless the OP is specific, it is impossible to give a correct reply.

 

[Doc W]

No suggestion...but that is why I raised the issue of minimum water line as a consideration, as well as min temp. Clamp height figures into things, too...most cooking is not done in really shallow vessel.

I just added "minimum waterline" to my parameters. Thanks! With this in mind, I may have to move to a deeper set of trays if the heater is too big to be fully immersed.

 

[Doc W]

Clive, give us an example of how you might solve this. I am not married to a particular idea if there is a better one out there which suits my needs. My main paper developer at this point contains both metol and hydroquinone. I have read that both of those ingredients are not dependable or consistent at lower temperatures such as 15C. I keep detailed notes when I am trying to arrive at a final print because I like consistency. Once I arrive at a development time, I want to be able to reproduce that print somewhere down the road. This is why I want to keep the temperature consistent. One less variable.

The temperature in the darkroom, with a space heater in it, settles out at 15C. That is not an uncomfortable temp for me. I just put on a second layer of shirt. I use oil heaters because they have no fans and thus don't move around dust. The temperature also varies unpredictably while I am in the darkroom. I had been using a small, very cheap and inefficient aquarium heater but I gave up on it because it was not the type which allowed me to set the exact temp. I discovered, only a few days ago, that there are heaters which allow me to set the temperature. I see that as solving the problem but I will have to try it out, hopefully some time this week.

What would you do in this situation to compensate for the lower temperature?

 

[Doc W]

I see a what looks like a temperature probe, but got no idea how this photo is related to our topic.

I think that what is being suggested is a water source at a constant temperature to feed a water jacket. This is still a possibility for me in the back of my mind. It just might be a little awkward given the physical arragement of my darkroom.

 

[AgX]

A rinsed water jacket. This idea could be new at Apug.

 

[Doc W]

A rinsed water jacket. This idea could be new at Apug.

Huh?

Looks blankly at AgX as if there is something I am not getting.

 

[pentaxuser]

The advantage of the sous-vie heaters is their impeller, disadvantage is their mounting .

Thus remains the (cheaper) immersed thermosthatic 25W aquarium heater.

Yes your bottom line is the solution I'd go for as well. Least costly by far, capable of keeping the temp within very close limits and there is very little to go wrong with one

My bigger concern, if the darkroom temp is low enough to seriously affect development, would be the effect a very cold darkroom would have on my comfort and its subsequent affect on my concentration and enjoyment

pentaxuser

 

[AgX]

Huh? Looks blankly at AgX as if there is something I am not getting.

You explained to me mschem's idea involves using temperature controlled tap water for filling that outer (jacket) bath. I replied meaning that to keep the temperature the idea likely was to have that water continuously run through the outer bath. And this I idea I did not come across here so far. Only filling an outer bath once with temperature controlled water as in C-41 processing in a (static) water jacket.

 

[Doc W]

You explained to me mschem's idea involves using temperature controlled tap water for filling that outer (jacket) bath. I replied meaning that to keep the temperature the idea likely was to have that water continuously run through the outer bath. And this I idea I did not come across here so far. Only filling an outer bath once with temperature controlled water as in C-41 processing in a (static) water jacket.

Ok, I get it. Yes, two different ways.

 

[cliveh]

Clive, give us an example of how you might solve this. I am not married to a particular idea if there is a better one out there which suits my needs. My main paper developer at this point contains both metol and hydroquinone. I have read that both of those ingredients are not dependable or consistent at lower temperatures such as 15C. I keep detailed notes when I am trying to arrive at a final print because I like consistency. Once I arrive at a development time, I want to be able to reproduce that print somewhere down the road. This is why I want to keep the temperature consistent. One less variable.

The temperature in the darkroom, with a space heater in it, settles out at 15C. That is not an uncomfortable temp for me. I just put on a second layer of shirt. I use oil heaters because they have no fans and thus don't move around dust. The temperature also varies unpredictably while I am in the darkroom. I had been using a small, very cheap and inefficient aquarium heater but I gave up on it because it was not the type which allowed me to set the exact temp. I discovered, only a few days ago, that there are heaters which allow me to set the temperature. I see that as solving the problem but I will have to try it out, hopefully some time this week.

What would you do in this situation to compensate for the lower temperature?

Well when I make up print developer, I do not use a thermometer. I put my fingers in the solution diluted between hot and cold until I think it is about 20c. From then on I adjust the exposure to suit the developer and dev time.