How Critical is developer temp for print processing?

[hoffy]

Howdy,

Since I started in the darkroom, I have always tried to eliminate as many variables as possible with the equipment I have, which includes trying to keep chems at the specified temperature. When doing films, I have found this easy, as I get a reasonable sized tub of water to the right temp, which stays constant enough for the whole process.

But, with trays and the such, I have found it hard to keep it within the range that I like, especially for developer.

I am using Ilford Multigrade dev(I should buy shares in the company.....I use Ilford everything!), where they specifically suggest 20deg C. My mains water temp at the moment is around 25deg C and my room temp is around 24 as well. While I can get the temp down to 19 or so before I start, it will and does creep up after not very long.

Should I be trying harder to get that temp down and more consistent?

Cheers

 

[jgjbowen]

I used to struggle with this all the time. It would take me about 1/2 hour to get the chemicals to the correct temperature prior to starting development and using a water bath to try and keep the temperature constant. Then I said the hell with it and purchased a Zone VI compensating developing timer. Now I just stick the probe in the tray of developer, hit the footswitch and start processing my stuff.

I did a test last year where I heated my print developer to 75 degrees then processed a print for "2 minutes" (about 90 second real time). I then cooled the developer to 60 degrees and processed another print for "2 minutes" (about 3 minutes real time). If you examine the prints next to each other you could never tell which was which.

The Zone VI compensating developing timer is hard to find these days, but there are other compensating timers available. Hopefully someone in the know will chime in with the details.

 

[Photo Engineer]

What John says is true, but only for some papers or developers or combinations of the two. Sometimes, higher temperature can lead to bad fog. I have experience with this, and it is a problem.

PE

 

[Ponysoldier]

Because paper is developed "to completion" - unlike film - this is much less of an issue! The "recommended" times and temperatures are intended to give you a starting point so that the third variable - exposure of the paper - becomes a little more manageable. Since your temperatures are on the warmer side it will require less time (because of the higher activity of the developer)... consistant time and temperature are important in order to match subsequent prints made from the same negative (at the same exposure). Higher temperature would become a problem if it rises to a point where maximum black is obtained before highlights are developed or the emulsion is damaged.

 

[MattKing]

I would email Ilford and ask them if they have any special recommendations for the paper and developer and temperatures you use.

They have a "Contact Us" page on their site:

http://www.ilfordphoto.com/contact.asp?c=Australia

As I understand it, they are privately held, but you could always ask about purchasing shares .

Matt

 

[fschifano]

I tend to think that it needs to get pretty warm before you start getting any extra fog. In summer, the temperature in my darkroom can get up to about 28 - 29C, and that's pretty warm. I've yet to see where that's caused me any problems that I can see. Development proceeds more rapidly than it does in winter, but that's really the only difference I've noticed. I did heat up some Dektol to about 38C once to see what would happen and that was hot enough to fog the paper pretty badly.

 

[Photo Engineer]

Well, after nearly 1/2 century of professional experience in processing and the design of developers, I can say that it varies. Notwithstanding other opinions, I have too much experience in processing and design of developers to say other than what I have already said.

PE

 

[tkamiya]

PE,

Can you give me an idea in about what temperature I should start worrying about fogging? This is a great concern for me as I live in Central Florida.

 

[Chuck_P]

I combat this by using a heating pad set to a very low temperature (all precautions against electrical shock are taken of course, quite innocent really). Anyway, I use the microwave to give short bursts to get my developer at the right temp, then place on the heat pad, did some testing to know where the pad needs to be set to keep it at 68 deg F. Works very well for me until I can do something else.

 

[brian steinberger]

I combat this by using a heating pad set to a very low temperature (all precautions against electrical shock are taken of course, quite innocent really). Anyway, I use the microwave to give short bursts to get my developer at the right temp, then place on the heat pad, did some testing to know where the pad needs to be set to keep it at 68 deg F. Works very well for me until I can do something else.

I agree. I bought a simple heating pad from Walmart a few years back. On its lowest setting it keeps my developer at a perfect 70 degrees.

 

[hoffy]

Sounds good for your situation, but unfortunately, I cannot seem to find cooling pads!

 

[Chuck_P]

Sounds good for your situation, but unfortunately, I cannot seem to find cooling pads!

LoL!, Sorry, to have commented in terms of winter temp control problems, but at least you know there's a temporary solution for that. The compensating timer is the way to go, I just haven't gotten one yet. In AA's The Print, there is a good discussion on "factorial" development. In short, it's a way to compensate (within reason) for changes in developer strength and temperature so that print consistency is achieved.

 

[Sirius Glass]

Not all that critical for black & white.

Steve

 

[MurrayMinchin]

Do you keep records? Do you have a control, or standard negative that you use to compare different developers and/or papers? One that prints well without dodging or burning at normal developing time at normal contrast, and has textured light and dark areas?

If you do, at the beginning of your next printing session (when the developer is fresh) measure your developers temperature; let's say it's 25C. Let's also say your normal developing time is 2 minutes. Take several large strips of paper that will include the important bits of the photograph and write on the back of them either 2 min, 1min 45 sec, 1 min 30 sec, or 1 min 15 sec and develop each of the identically exposed strips for that time. Compare the dried strips with the original print that was developed for 2 min at 20C, and see which time at 25C gave the same results.

If your enlarger gives consistent exposures, if you agitate consistently, and if the developers temperature didn't change during the test, you will have a good idea what "2 minutes" development time actually is at 25C. Repeat the test a few times at different temperatures and mark them on a chart. Pretty soon after that you'll be able to make educated guesses at what the proper time is at temperatures between the ones you've already tested.

Murray

 

[ricksplace]

Not all that critical for black & white.

Steve

I agree with Steve. All the above comments are good when applied to b&w processing of prints. Colour prints are another matter entirely.

 

[MurrayMinchin]

Not all that critical for black & white.

I wholeheartedly disagree.

I use fibre based B&W paper with a Glycin-Metol developer. Because I keep the working solution for up to several months, depending how much it gets used, I use the Emergence Time (ET) of the image in the developer, multiplied by a Development Factor (DF) to find development times. This developer has a slow image ET so I use the ET of the negatives clear edge multiplied by a DF of 4.5 for normal development. An ET of 40 seconds multiplied by a DF of 4.5 equals a developing time of 3 minutes. When the ET gets to about 48 seconds I toss it because developing times start getting too long for my tastes. This compensates for both temperature fluctuations and for the developer starting to run out of gas.

While it's true that exposure would have more influence in high print tones than longer developing times, there is a darkening of subtle textured high tones with longer development. This kind of developer also has a proportionally bigger effect on the lower print tones with longer developing times, which will also effect local contrast in the mid tones.

This method allows me to begin working with a negative from exactly where I left it, even weeks later, and to print duplicate fine prints without going through the whole test strip process all over again.

A cold developer at 3 minutes or a hot developer at 3 minutes would both completely change the final prints quality.

Pretty critical stuff for me.

Murray

 

[Ian Grant]

Murray's right temperature can be critical, but as \PE says it also depends on the materials, too low a temperature can be a big problem as MQ developers cease to work as effectively below about 18°C.

In addition at higher temperatures and shorter dev times there's a shift in image colour/tone with some warm-tone developer/paper combinations which some of us use deliverately, and as Ron mentioned you have to make sure that the higher temperature isn't introducing/increasing base fog.

But in general some people suffer poor print quality because they let the dev temperature drop too low, then they struggle to make good prints.

Ian

 

[pentaxuser]

Hoffy This is only anecdotal NOT scientific observations but in a good U.K. summer or good spell in summer my darkroom which is a converted bedroom is south facing, was non ventilated, permanently blacked out and by the evening could easily reach 23-25 degrees C. I may not have as good an "eye" for changes in print looks as others but I can't say I noticed any real changes at these temps and I use Ilford paper and chemicals.

I did notice changes in me however. After a couple of hours I had had enough for one session at these temps.

pentaxuser

 

[2F/2F]

FWIW, IME I have not noticed any difference in results printing in ambient temperatures ranging from about 10 C at the coldest to 28 C at the hottest. Usually my darkroom is a bit colder than the halfway point between these two extremes. I use Ilford Multigrade, Ilford PQ Universal, and Dektol (and Arista A+B for lith printing).

 

[hoffy]

OK, thanks for all the replies. I suppose, in the end, its going to be totally up to me to determine if there is any change. I am wondering if I just make a step wedge type of exposure, cut it in half, develop when the temps are down and again later when the temps are up to see if this makes any difference. I will find out tonight as we have quite a bit of hot weather on its way (estimated top of 34deg C today)

 

[Photo Engineer]

You have seen a wide range of answers here. I have tested dozens of papers over the years and have found, as I said, that it varies from product to product. One, Ilford MGIV in Dektol, hardly shows any change from about 65 F up to about 75 F, but over that same range several other papers show a considerable change. Some just went foggy and others became foggy and lost overall contrast.

 

[MurrayMinchin]

I use mine at 72 F because warm Glycin is happy Glycin

Murray

 

[Tony Egan]

I wholeheartedly disagree.

I use fibre based B&W paper with a Glycin-Metol developer. Because I keep the working solution for up to several months, depending how much it gets used, I use the Emergence Time (ET) of the image in the developer, multiplied by a Development Factor (DF) to find development times. This developer has a slow image ET so I use the ET of the negatives clear edge multiplied by a DF of 4.5 for normal development. An ET of 40 seconds multiplied by a DF of 4.5 equals a developing time of 3 minutes. When the ET gets to about 48 seconds I toss it because developing times start getting too long for my tastes. This compensates for both temperature fluctuations and for the developer starting to run out of gas.

While it's true that exposure would have more influence in high print tones than longer developing times, there is a darkening of subtle textured high tones with longer development. This kind of developer also has a proportionally bigger effect on the lower print tones with longer developing times, which will also effect local contrast in the mid tones.

This method allows me to begin working with a negative from exactly where I left it, even weeks later, and to print duplicate fine prints without going through the whole test strip process all over again.

A cold developer at 3 minutes or a hot developer at 3 minutes would both completely change the final prints quality.

Pretty critical stuff for me.

Murray

I agree. Using one's eyes and a simple technique such as Emergence Time is all that's needed. It's also a good method for assessing exhaustion of developer. For me, once emergence is more than about 35 secs at approx. 20 deg c. it's time to chuck it out. I generally use a 5xET including draining time - about 20-25secs for 11x14.

 

[nworth]

Australian summers can be brutal. PE's comments parallel my experience (over about the same period). Between about 18 and 23C there is absolutely no problem. At lower temperatures, things slow down. With some developers, things become unacceptably slow at 15C. As for high temperatures, most of the common, newer paper-developer combinations will work fine up to about 25C, or even 28C in some cases. A few might show some fog. Simply try to print a known negative with your usual combination at the higher temperature, and compare it to one printed under more normal conditions. Things may work just fine. If they don't, an ice water bath in a larger tray around the developer tray will help control things.

 

[Bruce A Cahn]

Too warm and the emulsion starts to come off in the corners from a long wash. Too cool and the wash may be incomplete. Another result of off temperatures is curling if you air dry the prints.