Alternative 2 to ORWO C 9165 – UT-18 in ECN-2 negative process

This article is about the development of ORWO UT-18 in the negative process as an alternative to ORWO C-9165.
The current status is as follows:

1. direct color development (ECN-2) 50 minutes of development at 20°C with Cinestill CN-2 and addition of 1.2g/l CD-3 and 50mg/l BZT at pH 9.65 (developer was already quite exhausted and was increased from pH 9.2 to 9.6 with 30g sodium carbonate)
2. Water thoroughly 30 minutes flow rinse
3. Bleaching bath 15 minutes, tested with 65g/l potassium ferricyanide (potassium hexacyanidoferrate(III) + 50g/l potassium bromide adjusted to pH 6.5 with 20g sodium dihydrogen phosphate (monohydrate) and 5-10ml 10% NaOH
4. Water 5 min
5. Fix 15 minutes, tested with Adox adofix P II 40g/l
6. Water 5 min
7. dry

Here are the results for a UT-18 135, good results can be seen around ISO6.

50min 50min – ISO 50 25 12 6 3

UT18 in ECN2 ph9.65 50mg BZT 50min standdev – Scene 1 ISO 50 25 12 6 3 1

UT18 in ECN2 ph9.65 50mg BZT 50min standdev – Scene 3 ISO 50 25 12 6 3 1

AGML battery charger

Here in autumnal weather and backlight – taken at ISO25. The slight blurring results from the shooting parameters 50mm f/2.8 1/30s.

UT18 in ECN2 ph9.65 50mg BZT 50min standdev – Scene 2 ISO 25

AGML battery charger

The negatives immediately after development.

UT18 ECN2 Negative 1

AGML battery charger

UT18 ECN2 Negative 2

AGML battery charger

What CD-3 typically does with (aged) UT-18 — technically explained

CD-3 is sterically substituted differently than CD-4/CD-1.

This influences:

• Diffusion in dense/aged gelatin (CD-3 can penetrate more slowly)
• Reaction rate with certain couplers (selective coupling)

In old UT-18 batches it often happens that the magenta layer is weakened in sensitivity or coupling (aging, sensitization differences).

If the developer (CD-3) reacts less well with the magenta coupler, less magenta dye is produced.

Consequence: When using CD-3 (or with poor coupling with the existing coupler), the positive/negative often looks greenish — because magenta is missing and cyan+yellow predominates. In other cases (depending on the exact coupler spectrum), CD-3 can also produce a yellow shift (more yellow, less magenta) or overall “dirtier” tones.

Kurz:

• CD-3 → common: magenta underformation → GREEN tinge (in UT-18 scenarios)