Darkroom Temperature

[IanBarber]

I have made a make-shift dark room in the attic ( 7 feet x 4 feet ) to develop my paper negatives.

There is no electricity up there and I am using battery driven LED's for the safe light. I have been watching the temperature of the room and it is about 50°F most of the time which means the developer is going to stabilise to about this temp. Is this just to low to even think about developing paper negatives in trays?

[pjd]

It's not too low a temperature to develop paper, but you'll probably get fed up of being so cold yourself. I had similar problems years ago with an attic darkroom but I found some old darkroom tray heaters (with thermostatic controls) in an antique shop. Or just get a room heater with a fan, a small space should heat up quickly.

[Doremus Scudder]

the temperature of the room and it is about 50°F most of the time which means the developer is going to stabilise to about this temp[/B]. Is this just to low to even think about developing paper negatives in trays?

From Elements of Black and White Printing by Carson Graves:

"... Hydroquinone is less predictable. At temperatures higher than 75°F, it is aggressively active, overemphasizing dark tones. As the temperature drops to less than 65°F, hydroquinone loses its ability to develop tones at all, leaving a print gray and muddy in the shadows."

https://books.google.at/books?id=0oL...eloper&f=false

If you're using a common MQ or PQ developer, you are going to have problems. I'd invest in a small heater and run an extension cord up the attic stairs.

Best,

Doremus

[Willie]

Take a look at the electric heaters that look like old water filled radiant heaters. They are filled with oil which heats and circulates in them and don't put out light. One small light to tell you it is on. Work well as they are quiet and even if the power goes out they radiate heat for awhile before cooling.

50 degrees is too cool for much darkroom chemistry to work well.

[IanBarber]

Take a look at the electric heaters that look like old water filled radiant heaters. They are filled with oil which heats and circulates in them and don't put out light. One small light to tell you it is on. Work well as they are quiet and even if the power goes out they radiate heat for awhile before cooling.

50 degrees is too cool for much darkroom chemistry to work well.

Thanks. I appreciate 68 is my target, what would you say is the minimum I should be aiming for

[John Layton]

....another reason that the oil-filled heaters are great is that they don't blow dust around.

Do understand that room temperature does not always equal solution temperature...that depending upon the relative humidity, agitation/air movements, trays and sink composition (heat transfer characteristics) - your actual solutions temps. may be different (typically cooler than) your air temps...so do test your solution temps. and set your room temp. accordingly!

Alternately, there is some merit to employing a "drift-down" scenario...starting with a solution temp. which is somewhat higher than your target with the knowledge that it will decrease a certain amount over the time of a given process. If you do do this just make sure the final solution temp. at the end of the developer step is not significantly below 65F.

Do keep in mind that absolute solution temps. are somewhat less important with papers than with films.

Finally...I do believe that there are developer formulations which are designed specifically to work well in cool temps. Maybe someone with more experience with this can chime in?

[IanBarber]

After someone mentioned oil filled radiators, I suddenly remembered we had one in storage in the garden shed. Ive cleaned it up and its working.

Do understand that room temperature does not always equal solution temperature...that depending upon the relative humidity, agitation/air movements, trays and sink composition (heat transfer characteristics) - your actual solutions temps. may be different (typically cooler than) your air temps...so do test your solution temps. and set your room temp. accordingly!

Thanks John, I will do some tests tonight. Looking at this radiator, the top is pretty flat and may even allow me to place my dev tray on it

[Luis-F-S]

There may not be any electricity now but I bet an electrician can set you up

[adelorenzo]

The Darkroom Cookbook has recipes for low temperature developers.

[Jerry Bodine]

...I have been watching the temperature of the room and it is about 50°F most of the time...

How about in the summer, when most attics get very warm? Will this not complicate your situation? Is your 7'x4' space a small part of a larger attic? Does your attic not have insulation on its floor to help maintain comfortable living quarters below, all year long? Depending on the type of insulation, it could be a "dusty hell."