Effect of developer temperature and dilution

[gbenson]

Hi all,

I've just started home processing B&W film, so I'm pretty new to all this. The datasheet for the developer I have (Ilfosol 3) lists times for 1+9 and 1+14, at 20°C and at 24°C, so for example it says I can develop Delta 3200 at EI 3200 by doing 11 minutes in 1+9 at 20°C, 17 minutes in 1+14 at 20°C, 9 minutes in 1+9 at 24°C or 11 minutes in 1+14 at 24°C. My question is, why would you pick one dilution-temperature-time over another? Would there be differences in contrast or grain size, for example?

Thanks,
Gary

 

[michaelbsc]

I've never used ilfosol 3, but be aware that the Delta 3200 times on the old data sheets were wrong. If you get very thin negatives don't assume you got it wrong. Yet longer times. I find Delta 3200 in DD-X is good. I would expect Ilfosol would be good too.

 

[gbenson]

That's interesting. I've noticed people advocating longer times, or saying to expose at 1600 but develop for 3200, maybe that's why.

 

[michaelbsc]

That's exactly the issue. The new data sheet may have been corrected, but it may not. I don't know. Just be aware and adjust accordingly.

As to your original question, yes. Different dilutions and temperatures do have some effect on the film. Also, in hot weather, maintaining 20 deg may be impossible. Do alternatives are presented.

Others can probably give more details about the effects.

 

[alef_fela]

The datasheet says it all:
http://www.blende7.at/datenblaetter/ilford/ilfosol_3.pdf

1+9 vs. 1+14 is a choice between image quality and economy.

Try to achieve 20 degrees C for developing, and use the 24 C value to interpolate the actual temperature you end up with.

Longer developing times or higher temperatures increase contrast, but the values you refer to are meant to generate equivalent normal contrast (GBar=0.62), observe that, for the same dilution, the times get shorter as temperatures rise.

 

[ic-racer]

Basics for Good Results:

1) Don't skimp on developer concentrate volume
2) Don't skimp on exposure

 

[Aurum]

The datasheet says it all:
http://www.blende7.at/datenblaetter/ilford/ilfosol_3.pdf

1+9 vs. 1+14 is a choice between image quality and economy.

Try to achieve 20 degrees C for developing, and use the 24 C value to interpolate the actual temperature you end up with.

Longer developing times or higher temperatures increase contrast, but the values you refer to are meant to generate equivalent normal contrast (GBar=0.62), observe that, for the same dilution, the times get shorter as temperatures rise.

As above. To be fair I haven't noticed the difference between the two dilutions, however with 120 film It's not really going to be noticeable.
There may be a difference at 35mm, but as I was developing SFX, which is not exactly a fine grain material, I couldn't see a difference. These days I use the economy dilution