Tom Kershaw
Subscriber
Having recently purchased a used Jobo 2850 drum with the intention of trying Ilfochrome printing at some point, I’d like to figure out how to make best use of the chemistry; although I’ve searched around on APUG, the kit seems to have changed within the last couple of years in terms of format and capacity. At present the kit appears to make 1000ml developer, 1000ml bleach, and 1000ml fixer. As a starting point, the capacity of the Jobo 2830 drum (for processing 8x10” paper) is 100ml. If the solutions are used one shot, the kit would last 10 prints, and at 45 GBP approx. per kit, this is rather too expensive, especially when considering initial experimentation. Can the developer, bleach, and fix solutions be replenished reliably? The following replenishment regime would give 13 prints per kit:
1st print: 100ml dev, 100ml bleach, 100ml fix, (900ml left)
2nd print: remove 50ml add 50ml fresh D, remove 50ml add 50ml fresh B, remove 50ml add 50ml fresh F (850ml left)
3rd print: 100ml fresh dev, 100ml fresh bleach, 100ml fresh fix, (750ml left)
4th print: remove 50ml add 50ml fresh D, remove 50ml add 50ml fresh B, remove 50ml add 50ml fresh F (700ml left)
Therefore 4 prints per 300ml, 3 x 300 = 900ml (12 prints) + 100ml (1 print) = 1000ml or 13 prints. This assumes all solutions are exhausted or age at the same rate which seems unlikely.
Assuming 16x20” prints in the Jobo 2850 drum:
1st print: 200ml dev, 200ml bleach, 200ml fix (800ml left)
2nd print: remove 100ml add 100ml fresh D, remove 100ml add 100ml fresh B, remove 100ml add 100ml fresh F (700ml left)
In this instance the kit lasts 2 prints per 300ml (300 x 3 = 900ml) = 6 prints + 100ml (half print) so 6.5 16x20” prints or 5 16x20” prints and 1 8x10” print per kit.
Are there any more complex or substitution replenishment schemes that can extend the capacity of the kit without compromising image quality and consistency? If my understanding is correct, the Ilfochrome bleach is the unique solution, the fixer being standard, and the developer slightly modified over a regular black & white print developer. I’d would like to emphasise I would intend starting with 8x10” paper.
Tom
1st print: 100ml dev, 100ml bleach, 100ml fix, (900ml left)
2nd print: remove 50ml add 50ml fresh D, remove 50ml add 50ml fresh B, remove 50ml add 50ml fresh F (850ml left)
3rd print: 100ml fresh dev, 100ml fresh bleach, 100ml fresh fix, (750ml left)
4th print: remove 50ml add 50ml fresh D, remove 50ml add 50ml fresh B, remove 50ml add 50ml fresh F (700ml left)
Therefore 4 prints per 300ml, 3 x 300 = 900ml (12 prints) + 100ml (1 print) = 1000ml or 13 prints. This assumes all solutions are exhausted or age at the same rate which seems unlikely.
Assuming 16x20” prints in the Jobo 2850 drum:
1st print: 200ml dev, 200ml bleach, 200ml fix (800ml left)
2nd print: remove 100ml add 100ml fresh D, remove 100ml add 100ml fresh B, remove 100ml add 100ml fresh F (700ml left)
In this instance the kit lasts 2 prints per 300ml (300 x 3 = 900ml) = 6 prints + 100ml (half print) so 6.5 16x20” prints or 5 16x20” prints and 1 8x10” print per kit.
Are there any more complex or substitution replenishment schemes that can extend the capacity of the kit without compromising image quality and consistency? If my understanding is correct, the Ilfochrome bleach is the unique solution, the fixer being standard, and the developer slightly modified over a regular black & white print developer. I’d would like to emphasise I would intend starting with 8x10” paper.
Tom