>At the moment i'm working in the classical way :
>**PAPER =3D Poggi( by Arches available only in Rome) Arches=
> Aquarelle/Platine
Try Fabriano Artistico satina from Milano.
**COATING =3D double by brush (i have also built an acrilic rod but only=
used
Size first with a 1 % size and you will need only one coat.
>**CONTRAST AGENT =3D potassium clorate in the sensitizer
Vary the proportions of platinum to palladium to give contrast control .
Potassium chlorate gives too much risk of ugly grain.
>**DEVELOPER =3D mostly ammonium 20=BAC.[77=BAF.] i'm trying to get neutral=
blacks
The classic developer is potassium oxalate which tends to give improved
gradation and highlight and shadow detail.
>**FIX: =3DKodak hipo clear. i used HCL but yellow everywhere at any
percentage.
Use three baths of EDTA disodium salt 5 % solution.
>**NEGATIVES =3Doriginal neg. enlarged onto 4x5 Kodak Tech.Pan,developed in=
> low
>concentration paper developer. positive enlarged onto N31P developed in Agfa
>G5, for final neg.(i started developing in HC110 but i had a very hight=
> fb+f).
If you are working at 5 x 4, FP4 developed in PQ Universal at 1 : 9 for around
two minutes, or Amidol, will give you negatives that will give you platinum
prints that will outshine the results you are getting now.
> i have seen few PT/PD prints really terrific.
This is really important. Many people think that their platinum prints are good
because they made them. Many modern platinum printers have never seen a good
platinum print and so have no criterion by which to judge their work.
>I have 2 problems:
>-A- lack of sharpness. I will experiment with paper, because i have mostly
>used POGGI paper that is very textured,if it will not succed i will try a
>different printing frame.
The texture is your main problem. The Fabriano gives beautifully sharp prints as
does Waterford.
>-B- Extension grays too short(blacks too closed / whites too short / Dmax
is ok)
You are using the wrong film and the wrong developer.
Try this way and forget the contrast controls.
Terry King