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Re: Basic Step tablet/UV light piesography question

2014-11-18 by jon@...

Just to add to this thread. I designed the curves for Methodology 3 to produce a linear film response to visible light. Meth 3 actually prints film base+ fog to the max density indicated by the curve names (1.40, 1.50, 1.60, etc...) The only curve that does not print film base+ fog is the Carbon curve which was at the request of Dick Sullivan when we were demonstrating it to him. Otherwise Carbon curve is same as the 1.60 curve. The system does not use black ink but rather shades 2, 2.5, 3, 4.5 and 5. This year we released a new P2 Dig Neg system that adds black shade 1, 4 and 6 and allows making digital negatives and K6 prints without having to change inks. And that is the latest system we are providing into 8 ink printers. It's matte only. On the X900 we offer it with matte and glossy print curves because there is enough ink slots for all including the GO. There have been at least three systems in between the latest and the first - so always make sure that the curves you are using match up to how you have installed the inks. My blog indicates this for each of the curve generations. It's very easy to confuse.

In January, I will begin to produce a new set of curves for PT/PD that are linear to UV - using a UV densitometer rather than the visible light densitometer that I used to make the Meth 3 curves. If you followed my blog when I was designing the system - there is a process I created in which I did linearize a curve directly to the silver paper - and the Piezography profiler forced the Ilford Multigrade to print with rather long tone associated with Piezography - and it just did not look like a silver print with its characteristic S curve. So, I abandoned that although I left the curve out there in the universe if anyone else wants to use it. I did not envision that silver printers would want to lengthen the tone of silver. Blaspheme! If I am wrong, it's worth a try using Ilford Fiber Base. You could probably rearrange the curve to match your Piezo Dig Neg current inks setup.

Digital Negatives: Getting very long in the shadow



For the UV system I do plan to linearize to a range of PT/PD chemistries. My thought being that it would help some without much PT/PD experience to enjoy an out of the box experience with making digital negatives for PT/PD. Also Pt/PD is more linear than silver so this type of curves generation would be welcome by UV sensitive printmakers. I have seen some extraordinary good platinum prints using the Meth 3 curve - but they required quite a bit of Photoshop curve correction to compensate for UV. At the Santa Fe workshops we make PT/PD prints that are immediately satisfying with a base PS curve we provide based on the work of David Chow for whom I designed the system. From first using that curve, we expect the users to bend the system to their own will. The PS curve making is the bit that I envision eliminating with the UV generation of curves.

My plan is to release this for the EPSON 1430 (still available). The 13" wide film is not enormous but the printers are inexpensive enough. Also, I never made a dig neg system for this printer. At the same time I will do the visible light curves. We know Piezo inks can trap UV - it's just a matter of how the ink is linearized.

We are also releasing a new multi-curve system based on the X880 platform (double quad) and the X900 platform (triple quad). These will allow selecting multiple curves to blend and split tone in QTR. This should release for xMas and I may follow up with dig neg for it sometime in 2015.

Welcome any suggestions, etc here or off list.

Jon Cone
Piezography

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