new digital neg system from cone

[WalkerBlackwell]

Huh. Than a guess the last 300+ prints I've seen run on 129 linearized PiezoDN .quads aren't real.

But for sure, there are "reversals" that show. The trick is to algorithmically correct for said reversals (laterally along the line instead of by measurement of multiple patches) and glean more accurate data from the total line than you would from a 21step.

That said, every target file of PiezoDN has a 21 at the bottom to enable self-checking.

best,
Walker

[WalkerBlackwell]

There is a screen-shot I included in the about section of the PiezoDN website that shows the smoother tool in action. I intentionally included SUPER rough reversals in there so you can see what it's doing.

QTR-Linearize-Quad droplets performs much better when you give it more data-points as I don't think it's doing truly stable interpolation for low amounts of patches (21). The 129 patches + control of the ink actually effectively makes Roy's linearizer into a very high-quality tool indeed.

Upcoming in PiezoDN is a 31x4 tool that will output 129 quadratic data to be used by the Linearizer. This may be just as good as 129 in that it will keep the linearizer from getting "wiggly" when given low amounts of data.

[Michael Rosenberg]

Bob and Michael,

Yes, the image in PS remains unaltered, and is how it appears in the negative. My test target has tone values with ink and k values making it easy.

I agree, it is very hard to see subtleties in tonalities in the silver gelatin print. I attribute this to the paper curve, where the slope blurs slight differences in tonalities. Try printing a Stouffer 21 step tablet. I found a 21 step target to be more than adequate, and the test target I provide has a 21 step strip and a Kodak Zone strip to allow either reflection densitometry or visual inspection. The ink curve is a PS curve, and it extends to the left to provide better shadow detail; for highlights I define LLK as grey ink and then use black boost (which only works on grey ink) to get increase in density at the right end of the curve.

By linearizing the inks it makes it possible to predict the effects on the negative density and changing the print. When Ron Reeder adapted QTR for making digital negatives for alt processes he started with paper curves, and then linearized using grey curve. If you changed one ink you changed the deposition of all inks. In my system if you change on ink you only change that one in, either increasing or lowering density in the negative. It is intuitive that the ink curve resembles the film curve for TMax films (you can even make it look like the film curve for other films too), and then relates to the paper curve. Remember, you can only correct the ink curve so far before running up against the paper curve. I know - I ran into this myself!

The system I developed and the files I provide are all plug and play. They work for Ilford and Adox papers. I have been using it for the past 5 years with no problem.

If you want to split contrast it is very easy to do. Simply add a separate PS curve for yellow or magenta inks using the toner function of QTR. I have done this a couple of times, and with the test target I provide it is easy to work out..

Again, send me a PM and I'll send you the files of curves, profiles, target image, and etc.

Mike

[WalkerBlackwell]

I am not here to defend or compete with anyone's system. Just wanted to add to the conversation. I'm super excited about PiezoDN because I think it hits a sweet spot of quality and simple adaptability needed by experimental analogue printmakers of all stripes (including myself and Jon of course). However, I'm not here to say it's better than anything else.
The users and viewers of PiezoDN will decide yay-or-nay after seeing its fruits in the flesh. There is a nice print at Latitude (possibly still there) that I did that anyone in Chicago is welcome to look at. And of course there will be many many more down the line.

Currently this system is bed-rocking the entire historic-process lab at Maine Media Workshops. Anyone in that region should check it out (or take a class!). There are some amazing genius darkroom people there. I was truly impressed by their abilities!

cheers all,
Walker

edit> www dot mainemedia dot edu/workshops/photography/historic-process-mentoring

Brenton is amazing

[Michael Rosenberg]

There is a screen-shot I included in the about section of the PiezoDN website that shows the smoother tool in action. I intentionally included SUPER rough reversals in there so you can see what it's doing.

QTR-Linearize-Quad droplets performs much better when you give it more data-points as I don't think it's doing truly stable interpolation for low amounts of patches (21). The 129 patches + control of the ink actually effectively makes Roy's linearizer into a very high-quality tool indeed.

Upcoming in PiezoDN is a 31x4 tool that will output 129 quadratic data to be used by the Linearizer. This may be just as good as 129 in that it will keep the linearizer from getting "wiggly" when given low amounts of data.

Walker,

Can you help me understand what you mean by QTR linearize Quad droplets? I am unfamiliar with this term. Are you referring to the ink droplets? And what do you mean stable interpolation?

Mike

[LesleyNowlin]

Currently this system is bed-rocking the entire historic-process lab at Maine Media Workshops. Anyone in that region should check it out (or take a class!). There are some amazing genius darkroom people there. I was truly impressed by their abilities!

cheers all,
Walker

edit> www dot mainemedia dot edu/workshops/photography/historic-process-mentoring

Brenton is amazing

Brenton is amazing! Such a great teacher. I love the Maine workshops too. Took the alt-process class and I learned tons of processes and found my love for Platinum a few years back. I'm looking forward to trying the PiezoDN. What if I need help setting it up? Do you have suggestions on where to go?
Thanks,
Lesley


Sent from my iPhone using Tapatalk

[WalkerBlackwell]

@lesleynowlin It's certainly a bit of time to set it up.

It requires a kit: Piezography ink, the cartridges, the software. All of the instructions can be downloaded right from each product and we also offer direct support at the private forum at PiezoDN. There is an extensive Piezography manual that comes with the system as well that covers far more than one can teach in a normal printing class.

best,
Walker

[WalkerBlackwell]

@bobcarnie yeah, we teach this. It's really the best way sometimes for people to come actually see what is possible. I think all our group workshops are sold out (they sold real quick so we increased from 5 to 6 students) but we do individual day-long stuff as well.

best,
Walker

[sanking]

"But for sure, there are "reversals" that show. The trick is to algorithmically correct for said reversals (laterally along the line instead of by measurement of multiple patches) and glean more accurate data from the total line than you would from a 21step."


Is the software that algorithmically corrects the "reversals" in the PiezoDN package?

Sandy

[Michael Mutmansky]

"But for sure, there are "reversals" that show. The trick is to algorithmically correct for said reversals (laterally along the line instead of by measurement of multiple patches) and glean more accurate data from the total line than you would from a 21step."


Is the software that algorithmically corrects the "reversals" in the PiezoDN package?

Sandy

Clearly, he's not using linearize without scrubbing the data first... which makes all the steps pointless with alt process. Might as well go with the 21-step curve at that point and not mess around with 129 steps.

At that point, a nice fine tuning of the curves can be done in finer steps successfully, but the linearize doesn't need to be done to so many steps.