Film developing questions

[FishyFish]

Ok, just a single question at present, but I may come back with more as I continue my, ahem, "development" in this area, hence the plural in the title.

I've been using my Ilfotec DD-X at 1:4 dilution so far, but might try it at the more economical 1:9 dilution at some point. For Delta 400, Massive Dev Chart only gives times for developing at 24° using this dilution.

My question is:

If my developer is at 24°, do the stop-bath and fixer need to be at the same temperature? And if not, will it affect the fixing times at all?

Thanks.

 

[Harlequin565]

No idea. I did hear that stop & fix should be at the same temp as the dev, but I've never done it. Both chems get stored at room temp and used at room temp in my house.

https://www.ilfordphoto.com/amfile/file/download/file/1915/product/685/

Scroll down to page 5. Take the 1+9 time at 24 degrees from the MDC app, and follow the line back to get a time for 20 degrees. That's what I'd do.

Actually, further down that tech sheet, it says

For best results it is recommended that all process solutions are kept at the same temperature or at least within 5ºC (9ºF) of the developer temperature.

And that's from the experts.

 

[StephenM]

Developer temperature matters for a couple of reasons: time depends on temperature, and at least one developing agent doesn't work at low temperatures (54 F from memory).

Other chemicals are not really temperature dependent for their action, but a sudden drop of temperature can crack the emulsion, leading to a crazy paving effect called reticulation. I had this happen once (1966), and ever since have been very careful of temperatures especially the wash water.

It has been said that modern films are more resistant to reticulation, and Monochrome Darkroom Practice by Jack Coote of Ilford writes of it being caused by a sudden extreme drop, which implies to my mind more than a degree or so. However, we are now seeing a resurgeance in older type films on the market. Some do have a reputation for being less scratch resistant than modern ones, so I'd err on the side of caution.

I believe I put an example of reticulation on my OneDrive to post a link long ago; if still there, I'll post again later.

 

[StephenM]

I'll just add. Extreme reticulation has the crazy paving effect; "mild" reticulation can pass as increased grain.

And just to round off what happens if the temperature is too high - the emulsion can come away from the film base. So, not advised to boil a severely underexposedfilm overnight in developer to get an image

 

[AZ6]

Take the 1+9 time at 24 degrees from the MDC app, and follow the line back to get a time for 20 degrees. That's what I'd do.

This. It can take a bit of trial and error, but should generally give decent results. I use weaker dilutions of developer, and longer development times (with subsequent less agitation), which I find give more sharpness to the negs, as well as an improved tonal range. You do get a bit more grain, but I like that. I use times that are not on the chart, I just used a rough formula based on the chart info to calculate what a suitable time might be, then went from there. I found that maintaining 24º a bit tricker than 20º, cos ambient temp can be lower than 24º except for the warmer months. So use a large waterbath to bung yer tank in between agitations; this can help maintain a steadier temp.

 

[john.margetts]

Mostly, you can compensate for variations in temperature by adjusting development time using the graphs provided by the developer maker. Ilford do not recommend diluting this developer to 1+9 - this might just be because they haven't thought of it but there might be a good reason. As you dilute the developer, the various ingredients will be affected slightly differently. It might be necessary to compensate for these differences by increasing the temperature. Or the good people at Massive Dev Chart might not have tried it at 1+9 and a lower temperature.

I always start as instructed then when I have good results, fettle the process. Stop bath temperature and fixer temperature is not important with modern films. I remember trying to deliberately reticulate a film and found it to be just about impossible even with much larger temperature differences.