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In another thread, @Ian-Barber had an extended conversation about higher dilutions of D-23. This led me to be curious about really high dilutions of both D-23 and DK-50. @Raghu Kuvempunagar suggested this would be possible by addng 0.5g/l of lye (Sodium Hydroxide or NaOH) to the highly dilute developers to jack up their alkalinity. I caution the reader - full concetrate lye is nasty stuff and yields unpleasant chemical burns and should only be handled if you know how to work properly in a lab, with good ventilation and bodily protection..
I did a variety of tests in 3 formats: 35mm, 120 9x6, and 9x12 sheets. Not all developers were tried in all formats, nor were all dilutions. All tests were done using 3 min prewet, 2min initial continuous agitation, standing, 10-15 sec agitation at 31 min, and completed development at 60min, nominal 68F (semistand development).
So, the following should be understood to be provisional results subject to more testing:
Next up will be to try the higher dilutions of D-23 and DK-50 see how much difference the lye actually makes.
I did a variety of tests in 3 formats: 35mm, 120 9x6, and 9x12 sheets. Not all developers were tried in all formats, nor were all dilutions. All tests were done using 3 min prewet, 2min initial continuous agitation, standing, 10-15 sec agitation at 31 min, and completed development at 60min, nominal 68F (semistand development).
So, the following should be understood to be provisional results subject to more testing:
- D-23 1:3 and DK-50 1:3 both work fine without any lye being added and yielded well managed negatives.
- D-23 1:9 and DK-50 1:5 with 0.5g/l of lye added also produced well managed negatives.
- D-23 in either dilution seemed to give better sharpness than the DK-50 in either dilution. That is, reducing solvent effects for higher acuity seemed more evident with dilute D-23 than DK-50.
- DK-50 in any of the dilutions produced noticeably less developer compensation effects than did the D-23.
- Highly dilute D-23 makes grain really visible in 35mm - at least it did with Kodak XX film. Since I've never tried the film with my more usual development practice, I cannot yet comment on whether or not it's the film or the developer, but I strongly suspect it's the latter.
Next up will be to try the higher dilutions of D-23 and DK-50 see how much difference the lye actually makes.