Greg,
On the FP4+ not enough density for Pt printing: try PyrocatHD. I actually use HP5+ for 8*10 , process it in Xtol, and if I feel the image would work in pure Platinum I bleach the negative and re-develop in PyrocatHD. Prints fine for pure Pt, albeit sloooow (aprox. expose for 1 hour...).
best,
Cor
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