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Paper developing time


I agree, and that's why factorial development is the way to go for me.
 
I use Ilford's RC paper and Dektol at 1+2. Using a cheap kitchen timer, I develop it for 60 seconds. What I see (in safe light) is that in first 15 seconds or so the image will appear and in next 15 seconds, consistently darken then reaches a stage where nothing seems to change. 60 seconds is double of that timing. Leaving it in for 2 minutes didn't change a thing. So after the initial 30 seconds of rapid change, the process slows significantly.

As Ralph says, I'm sure development is continuing as if I leave it in for 30 minutes, the whole thing will turn black! (I forgot once)
 
I'm new to printing and have experience with only one paper. This is Fomalux 312. It's silver chloride, RC, contact speed. This paper definitely changes with time left in the developer.
 
I was taught to alwys keep the variables to a minimum. I try to to use the same F srop on my enlarger, and always the same developement time. Dekto 2:1 for 2 minutes. As stated before, makes repeatability way easier.
 

You may need a side-by-side comparison to see the difference and a densitometer to realize that MGIV-RC doesn't reach Dmax after 60 s or that there is a change from 60 to 120s (see my earlier post).

However, your experience can be used as prove that Dmax is overrated, which I think it is.

Let's keep in mind that paper manufacturer instructions about development times are all fairly old. When I highlighted their optimistically short development times to them, I was told by Ilford Technical Support that the times were meant for commercial processing, where speed is of the essence. Careful custom printing requires longer times to get full tonality!
 
Ralph,
In that case there must be an optimum. Manufacturers recommendation may be to short, but leaving e.g. Forte Polywarmtone in developer for, lets say 5 minutes will reduce contrast. Can you recommend a factor, for example, 1,5 times the time indicated by the manufacturer? I do not recall reading this in your book...

Jaap Jan Helder
 

Jaap

This is an omission in the 1st edition but is covered in detail in the 2nd. My recommendation is to follow AA's advise and use factorial development with FB-base paper.

Factorial development relies on the photographer noting the emergence time for a specific image tone in the developing bath and multiplying this time by a development factor to determine the total print developing time. Typically the emergence time of the midtones is multiplied by a factor of 4 to 8 to calculate the total development time.
 
Thanks for that. I recently acquired the processmaster, so I will put it to use in paperdevelopement too.
 
Ilford's recommendation for FB papers is 2 min. Is it safe to say that it should be 3 min? I've never noticed any lack of tonality in my prints from 2 min development time, but then again I've never tried 3 min to see a difference. My prints always appear around 35 sec, so with factorial development this would be 140 sec or 2 1/2 min.
 
Ian Grant said:
This ONLY applies to bromide papers.

Ian
Click to expand...

This is a common misconception regarding development to completion. I have seen this effect with Chloride papers as well. They develop to completion in about 1 minute. Many mixed Chloro Bromides do not do this.

Bromide papers can appear to develop to completion, but they do not, just as Azo paper can be further developed by a water bath, the Bromide papers continue very slowly.

Actually, development takes place rapidly and then slows almost to a halt with most pure Chlorides. The same is true of Bromides with some incorporated accelerants. Thus they appear to develop and then halt, but what they have done is slow down almost to a halt. In the case of Chlorides, it is an effect of the developer, but with the Bromides it is often a case of exhaustion of the accelerant added by the manufacturer to the coating. With Chlorides, the developer, if it contains Bromide or an antifoggant, is stopping or slowing development.

As for the original post, it is best to use the manufacturers suggestion for the paper of choice or the developer of choice. Note the rate of development and when things seem to stop, then development has gone pretty much to completion and fog will soon follow. Use the same conditions forever after with the same paper and developer combination.

PE
 
I do 1:00 - 1:30 for RC papers and 2 - 3 minute starting times with factorial development with FB paper. My developer is never fresh. I just add juice to it as needed.
 
PE

Please take a look at my test results in post #14. They show a quite different development characteristic.

1. 'development to completion' is a bit of a myth
2. development is never really complete
3. fogging most likely occurs before development is 'complete'
4. 'near completion' takes longer than manufacturers recommendation
 
Last edited by a moderator:

Ummm. Ralph, I was agreeing with you and kind of sort of disagreeing with Ian.

There is no absolute.

Development continues but is rapid, then slow, and during the "slow" phase, fog begins to form. Chlorides show this more than any paper if done in a developer which contains a Bromide antifoggant (Dektol is an example). They reach Dmax in as little as 20 - 30" and then stop (or appear to).

Now, take a Bromide paper with an accelerant such as a deveoping agent or a polymer. It appears to stop, but what has happened is that the accelerant has either diffused out or been used up!

I remember the old papers that just kept going and going. Finally highlights began to block and then the paper fogged. So I am totally in agreement with you and could offer many plots of development vs time showing speed, contrast and fog.

PE
 
Photo Engineer said:
Ummm. Ralph, I was agreeing with you and kind of sort of disagreeing with Ian.

There is no absolute.
PE
Click to expand...

There's no misconceptions either.


I agree with Ralph on this.

The issue is with Warmtone Chlorobromide/Bromochloride papers where there it's possible to vary the exposures and development times/dilution etc in a way that's not possible with a straight Bromide paper. The extremes that were possible with older papers which had cadmium in their emulsions have largely gone but there's still a good degree of flexibility. Lith printers also use the extremes though to get some colour effects from warm-tone papers.

Ian
 
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