I recently had a delivery of Platine, ordered before Richard posted
this, of batch 53445.
I ran some tests both with and without Tween 20 after talking with
Martin Axon about the problem and this is what I found.
Firstly, let me say that 90% of my prints are made on Platine with a
50-50 mix of Pt-Pd. The other 10% is on Cranes Platinotype with a 25-75
mix Pt-Pd. I've had great success using Tween 20 with the Cranes, but
have never had one successful print using it with Platine. Consequently
I never use it with Platine.
Martin tells me he's noticed that this batch is difficult to clear and
has a mottling that disappears when dry.
The tests WITHOUT Tween 20 coated smoothly and without problems, in fact
the results are no different from any of the prints that I've made in
the past on supposedly "good" batches.
The ones WITH Tween 20 just sank right in before I had time to spread
the sensitiser, as I've always found to be the case. They weren't
difficult to clear but did show mottling, but I think that this is a
problem with the Tween/Platine combination rather than this particular
batch.
Both series were developed in Potassium Oxalate @ 75 degrees F and
cleared in EDTA.
I'm not sure what this proves "scientifically", but aestetically I don't
seem to have a problem with this batch. I'd be interested to hear if
anyone else has had good/bad results.
Thanks
Keith Taylor