Linearized Curve - Image tonality question


#1

I created a Linearized curve from the Spyder 129 step DN that I printed using the 1430-PiezoDN-Master.quad, and then successfully created a new Master-Lin curve (with lots of your help). I process-printed the DN using the Piezo variables from the 1430 Technical Data: 100% Palladium (with F.O. #1 equal to the Pd) and room temperature Potassium Oxalate Developer, on Arches Platine.

My prints from about two years ago used Jon’s older curves, and my chemicals were 50-50 Pd-Pt with Amonium Citrate developer.

The older prints were much cooler than what I’m seeing in these new prints. I prefer a cooler tonality. I understand A.C. Developer prints cooler than P.O, and I believe the addition of Pt would in theory also add to the print being somewhat cooler.

Q> Do you agree with the above assumptions?

If yes, then I would plan to create a new curve.

Q> Can I simply make a new 129 step DN also using the master.quad curve, and then print it with my preferred process of 50/50 Pt/Pd plus A.C. Developer, and then scan it and create a new linearized curve?

Q>Do you see any issues or potential problems with this plan?

Attached is a small print (3x4.5) that hopefully allows you to see the warmer tonality. I just added another print, really small: 2x3 that may provide another tonality view. (the prints are a lot sharper than the scan!)

Thanks…Robert

 

 


#2

Yes. 50:50 Pt/Pd developed in AC will be very neutral (I wouldn’t call it cool unless it’s bluish!) compared to all Pd developed in PO. It will also be a bit contrastier, and depending on paper may require a bit more exposure. Pt is less sensitive than Pd. I’ve seen cases where AC is significantly more contrasty than PO even with all Pd, but I think that is an exception. Either way, you really should reverify correct exposure time for any significant change in process, and this is significant.

You will need to make a new linearized quad curve for this combination. You can make it from either the Master or from your linearized Pd-PO curve. On Platine I don’t think the change will be large enough to require an adjustment to the ink limits.