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IanBarber
14-Aug-2017, 14:52
Has anyone got one of these and use it for black and white developing.

According to the spec sheets, the min temperature is 25 but I did read a forum post (cant find it now) where someone said it will work at 20 C

Can anyone confirm this

docw
14-Aug-2017, 19:25
I pursued the same question a while back but couldn't find any with a minimum temperature below about 25C. Good luck.

Peter De Smidt
14-Aug-2017, 19:39
I have an Annova. I can check tomorrow.

IanBarber
15-Aug-2017, 05:00
I have an Annova. I can check tomorrow.

Thanks Peter

Peter De Smidt
15-Aug-2017, 08:17
I have an Anova Sous Vide Precision Cooker, WIFI 2nd Gen, 900 Watts
There's no problem using it at 20 C, assuming that the room temperature is below that.

monsta
15-Aug-2017, 09:17
Is it a bit of overkill for b+w?

Peter De Smidt
15-Aug-2017, 09:24
There are certainly cheaper ways. I bought mine for $130 on Amazon's sale in July. Recently, I've seen them for $30 off. I expect there will be good deals before the holidays. I use mine just for cooking, as I have a Jobo.

IanBarber
15-Aug-2017, 10:01
Is it a bit of overkill for b+w?

Out of interest, for bw how far either side of 20 do you think you can go before it effects anything

Peter De Smidt
15-Aug-2017, 10:19
There are two issues. The first is that changing temperature will change the amount of development. Developing 1 degree warmer, for example, will lead to more contrast. (As will increased agitation or developing for a longer time.) Assuming good consistency elsewhere, a difference of a degree + or - shouldn't be a big deal. T-grain (or similar) film changes more quickly than older style film does to these types of changes.

The second issue is that some developers, such as hydroquionine, become inactive below a certain temperature. I don't remember what that is, but it's pretty cold.

Consistency is the key to repeatable results.

IanBarber
15-Aug-2017, 10:48
The first is that changing temperature will change the amount of development. Developing 1 degree warmer, for example, will lead to more contrast. (As will increased agitation or developing for a longer time.

I have always been concerned about my setup but to be honest, I wasn't aware it was this critical. I also was not aware that T-Grain films change more quickly and I use TMAX 100 which I think is T-Gran and also FomaPan but not sure what that one is.

I am currently using a plastic food container with an aquarium heater in it but I do find it takes forever to bring the water up to temperature and I also have to mess about increasing the water temp to get the chemicals close to 20 which is probably because I do not use a pump to circulate the water.

I know the sous vide precision cooker seems an overkill but if it can do the job efficiently and maintain stable temperatures then it might be a good investment.

dasBlute
15-Aug-2017, 11:27
For color, it'd be handy...

For b&w, the only time I've had temp change drastically [+5 deg] during development was when I was doing tray development,
the heat from the fingers raised it over time...

frankly, other variables such as field-work, your metering, your meter itself, your shutters, lens flare, etc,
will provide more variability problems for quite a while. I keep my chems all in the same room, and develop at room temp.
typically between 68-75, below and above that, I won't do it.

Peter De Smidt
15-Aug-2017, 11:30
People have been developing in bathrooms for decades using tap water and a dubiously accurate thermometer, and the can get decent results, but there us someting to be said for consistancy. In my opinion, using an Anova would do. A better job than an aquarium heater, edpecially one without a pump. The Aniva is mire precise, consistent, and accurate than a aquarium heater. I expect it'll kast longer. The only downside is the orice. Get it in sale, if you can.

Sorry for the typing errors. I'm using my phone.

IanBarber
15-Aug-2017, 11:58
I am do doing a lot of minimal agitation with PyroCat at the moment and the ability to put the SP-445 tank back into the water bath during the rest periods knowing its at a constant temperature interests me.

kaif
18-Aug-2017, 14:03
I use a 'Videmaster' sous vide unit for my C-41 processing, and you can set these to as low as 0.5 degree Celsius. I never used it with b/w so far though. I used to do some pyro developing a while ago, before I had the sous vide unit, with a heating plate for brewing and one of these brewing temperature controllers, holding the mantle bath in a large brewing bucket at 24 degree, and that worked ok.

There is only one problem I could see using the Videmaster or a similar unit for b/w, if aiming to hold your temperature at 20 degree Celsius, at least for me: Room temperature itself is quite regularly at 22 degree or above in my darkroom before I even start, and of course the sous vide units only heat and just switch off when they reach their target temperature, so it won't help you to get the temp down! (Sorry, that was probably really obvious, but thought I mention it just in case!)

Some brewing set-ups do involve a heating plate inside a small refriderator... if you really wanted to go down that route - but I'd regard that very much as an overkill for b/w processing. Getting a mantle bath to the right temperature and keeping the tanks and developer in there works fine for me.

MartinP
22-Aug-2017, 06:48
A washing-bowl containing 15 litres of water at 20C isn't going to change appreciably, up or down, during ten minutes at normal room temperatures is it? Possibly in the desert somewhere during the day, or an unheated shed in the Arctic Winter, but generally 20C is more or less "room temperature". In more extreme cases, a few layers of bubble wrap around the bowl will be sufficient insulation.

When mixing cold or hot concentrates in to a working solution that should be used at 20C it is perhaps sensible to use warm/cool water for dilution, rather than try to temper the cold/hot solution in a water-bath. Noting also that many materials manufacturers give adjusted times for 24C and/or suggest time compensation, using graphs or other guidelines, for temperatures near 20C.

Peter De Smidt
22-Aug-2017, 07:03
I develop at 75F, as that's warmer than my darkroom ever gets. Pick a temperature that's convenient, and then adjust dilution of developer to get a good time. Too short of a time, and one risks uneven development or difficulties with consistency, and too long of a time is inconvenient. I prefer 8 to 10 minutes.