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Basic Step tablet/UV light piesography question

Basic Step tablet/UV light piesography question

2014-11-17 by petergcane@...

I've a couple of quick questions I'm hoping someone with experience can answer. On his website at


http://www.inkjetnegative.com/images/RNP/rnp.htm#The Big Picture,


Micheal Koch Schulte suggests that determining the best ink color to use for digital negatives is dependent on the light source used. You can see a big difference between UV and tungsten in his testing. What about differences between UV light sources themselves, he doesn't address it but is it an issue?


I use a 28V 1200 Mercury vapor lamp. If I am using piesography inks and their carbon curve (as I am) does their curve match my light source? It might if they used the same lamp but they don't say, is the difference great enough I need to worry about it?


From the little research I did, it looks like a few people looked into the RNP array method of making curves back in 2007-I saw Sandy King's post about where he tried it and didnt seem happy with it,but since no one as far as I can tell has really taken it up.


Its not proprietary, and seems to make sense. I had a difficult time unserstanding his direction for picking out the color to use for the negative, specifically his direction on picking a white square next to a black one, is anyone here using it to create curves? Any problems? Any successes?

Thanks for any thoughts..

Peter

http://marketingimagephotography.com/


Re: Basic Step tablet/UV light piesography question

2014-11-17 by sanking@...

The RNP method is conceptually similar to Mark Nelson's PDN system. Both methods have a method for first determining the blocking density needed for your process, and the required density range, and secondly have some method linearizing with an .acv curve. Both methods work fine with printers that have inksets with good UV blocking. I have made good digital negatives with both PDN and RNP but you are limited with both methods by the Epson driver. I now use QTR because of the much greater control of individual inks.

For some additional information on UV lights see the article Light Sources for Contact Printing

Sandy

Re: Basic Step tablet/UV light piesography question

2014-11-17 by sanking@...

Peter,

You are using the Piezography Methodology 3 ink set, right? If your are not getting the results you want with this inkset and the Cone profiles you can always create your own profile with the regular QTR tools. The existing Cone profiles for the Methodology 3 system basically are designed to give negatives with a defined density range, but you must adjust for input/output with an .acv curve. If you write your own profile for the Methodology 3 ink set you can insert both density range and linearization directly into the profile.

Sandy

Re: Basic Step tablet/UV light piesography question

2014-11-17 by sanking@...

Peter,

Or, you could use the method suggested by Roy Harrington for linearizing K7 inks where you create and apply an ICC custom file over the existing .quad file. In the case of the K7 inks this would probably be simpler for some than creating a new profile from scratch.

Sandy

Re: [QuadtoneRIP] Re: Basic Step tablet/UV light piesography question

2014-11-17 by Michael King

Just so that people don't get confused, let's be clear that creating an ICC profile DOES NOT linearize anything. It simply gives you the ability to preview your print output on screen. BUT that also depends on you having an accurately profiled monitor to view it !!

Any linearizing with this ICC approach is manual based on tweaking a PS curve and good luck with doing that accurately if your monitor is not high end and recently calibrated.

Mike
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On 17 November 2014 21:25, sanking@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:

Peter,

Or, you could use the method suggested by Roy Harrington for linearizing K7 inks where you create and apply an ICC custom file over the existing .quad file. In the case of the K7 inks this would probably be simpler for some than creating a new profile from scratch.

Sandy


Re: [QuadtoneRIP] Re: Basic Step tablet/UV light piesography question

2014-11-17 by petergcane@...

Sandy ,

I do use quadtone rip to print negatives with Jon Con’s method 3 curve. But I’m not sure I understand, (there's no surprise there) why I couldn't print the HSL color Array on Pictorico, using the Quadtone rip driver with Jon Cone’s QTR Curve for OHP

(NewS9aNG2b-PictoricoUPohp.quad.)

Then print that to determine which color provides the best UV blocking…Picking up from there I would as previously described,

> Create a step wedge with the chosen grey/color blend, and determine the new Dmax exposure time for the tissue with this new color.

>

> Create Chart Thob step tablet filled with the color chosen and print it.

> Scan the print into photoshop and analyze with Chart Throb. Save the Chart Throb Curve.

>

> Create another CT step tablet (or use an image) with the new curve applied to a positive. Apply the color picked to the tablet and print.

Re: [QuadtoneRIP] Re: Basic Step tablet/UV light piesography question

2014-11-18 by sanking@...

"But I’m not sure I understand, (there's no surprise there) why I couldn't print the HSL color Array on Pictorico, using the Quadtone rip driver with Jon Cone’s QTR Curve for OHP."

I am not saying you could not do that. But if the goal is to find the right UV blocking density of the Cone digital negative inkset, be aware that Cone provides profiles that will print to a rather wide range of effective UV blocking density. In practice you should be able to choose one that will print with the right blocking density for your process, then go directly to creating an .acv curve.

Testing for density range should be quite easy. First, find the correct printing time for Dmin with your OHP, then print out several step wedges with different profiles. Makes prints from the negatives and evaluate the prints. The correct profile for your process would be the one that has full shadow density at 95% or 100%, and some slight differentiation between 0% and 5%, with 0% almost or fully paper white.

Sandy

Re: [QuadtoneRIP] Re: Basic Step tablet/UV light piesography question

2014-11-18 by Roy Harrington

Hi Mike,

I think we still need some more clarification here.
Creating an ICC profile characterizes a particular print workflow -- (either B&W or for most of the world RGB).

This ICC profile can be used is several ways.
First -- the major usage is to print via a color management system that converts your image file to
values that "best" represent the colors/tones to match screen-to-print. This involves applying correction
curves on the fly -- calculated from the embedded profile and the print profile.

Second -- soft proofing in Photoshop with several options is possible. You can show what the print would
look like WITHOUT printing through the profile (this is the "Preserve Color Numbers) or what it would look like
WITH using the profile for printing.

So while your statement "creating an ICC profile DOES NOT linearize anything" is technically true -- after all it
doesn't modify the curves at all -- I think you are missing the main effect. It allows the CMS to create a
correction curve at print time to match screen-to-print. This is really the best of all methods -- all at once.
Sure this limited by rest of system but everything is anyway. Most modern displays are very good right out of the box.

At little about linearization. QTR driver linearization is based on straight-line L values. It's the "QTR driver standard"
basically so that all curves have similar responses. But in a sense is really an intermediate stage that for one
thing allows predictable curve blending. When you linearize a curve the software creates and applies a correction
curve to get a linear L-value output. It also allows the generic ICCs Gray-Matte-Paper for a lower dMax and
Gray-Photo-Paper for a higher dMax. The generic ICCs are for any linear L-value curve.
The Piezo K7 curves are a slightly different linearization -- I believe he picked one closer to Gamma 2.2 which is
his "workflow method" -- so that he could use a No Color Management workflow. This is easier on Windows w/ QTRgui,
and worked well on older Macs with Photoshop. But since CS4 correct NoCM has not been available -- so
that's why there's Print-Tool now.

There's a lot of nitty-gritty complicated stuff here but really its the icing on the cake. You can quite successfully
just make test prints and correct as needed by editing. The fancy stuff is generally needed for color work but B&W
is much more of a personal choice of all the possibilities -- try out various blends for toning, burn/dodge i.e. darken/lighten
areas of the print that you want that way. Don't get hung up on the "best" curves & workflow. "best" comes from
you editing to your image so it looks like what you want.

Roy

Show quoted textHide quoted text
On Mon, Nov 17, 2014 at 2:47 PM, Michael King drmrking@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:


Just so that people don't get confused, let's be clear that creating an ICC profile DOES NOT linearize anything. It simply gives you the ability to preview your print output on screen. BUT that also depends on you having an accurately profiled monitor to view it !!

Any linearizing with this ICC approach is manual based on tweaking a PS curve and good luck with doing that accurately if your monitor is not high end and recently calibrated.

Mike

On 17 November 2014 21:25, sanking@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:

Peter,

Or, you could use the method suggested by Roy Harrington for linearizing K7 inks where you create and apply an ICC custom file over the existing .quad file. In the case of the K7 inks this would probably be simpler for some than creating a new profile from scratch.

Sandy


--

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
Digital Negatives: Getting very long in the shadow
Piezography Digital Negative number nine, number nine, number nine, number nine… Number thirty actually.
View on www.piezography.com
Preview by Yahoo



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

Re: [QuadtoneRIP] Re: Basic Step tablet/UV light piesography question

2014-11-18 by Dr. Elliot Puritz

I think Roy makes an excellent point: One can edit a black and white ink jet print "on the fly" i.e., LOOK AT THE PRINT and change  edits to fit the print rather than the monitor.

Elliot 





Sent from my iPhone
Show quoted textHide quoted text
> On Nov 17, 2014, at 6:51 PM, "Roy Harrington roy@... [QuadtoneRIP]" <QuadtoneRIP@yahoogroups.com> wrote:
> 
> Hi Mike,
> 
> I think we still need some more clarification here.
> Creating an ICC profile characterizes a particular print workflow -- (either B&W or for most of the world RGB).
> 
> This ICC profile can be used is several ways.  
> First -- the major usage is to print via a color management system that converts your image file to
> values that "best" represent the colors/tones to match screen-to-print.  This involves applying correction
> curves on the fly -- calculated from the embedded profile and the print profile.
> 
> Second -- soft proofing in Photoshop with several options is possible.  You can show what the print would
> look like WITHOUT printing through the profile (this is the "Preserve Color Numbers) or what it would look like
> WITH using the profile for printing.
> 
> So while your statement "creating an ICC profile DOES NOT linearize anything" is technically true -- after all it
> doesn't modify the curves at all -- I think you are missing the main effect.  It allows the CMS to create a
> correction curve at print time to match screen-to-print.  This is really the best of all methods -- all at once.
> Sure this limited by rest of system but everything is anyway.  Most modern displays are very good right out of the box.
> 
> At little about linearization.  QTR driver linearization is based on straight-line L values.  It's the "QTR driver standard"
> basically so that all curves have similar responses.  But in a sense is really an intermediate stage that for one
> thing allows predictable curve blending.  When you linearize a curve the software creates and applies a correction
> curve to get a linear L-value output.   It also allows the generic ICCs  Gray-Matte-Paper for a lower dMax and
> Gray-Photo-Paper for a higher dMax.  The generic ICCs are for any linear L-value curve.
> The Piezo K7 curves are a slightly different linearization -- I believe he picked one closer to Gamma 2.2 which is
> his "workflow method" -- so that he could use a No Color Management workflow.  This is easier on Windows w/ QTRgui,
> and worked well on older Macs with Photoshop.  But since CS4 correct NoCM  has not been available -- so
> that's why there's Print-Tool now.
> 
> There's a lot of nitty-gritty complicated stuff here but really its the icing on the cake.  You can quite successfully
> just make test prints and correct as needed by editing.  The fancy stuff is generally needed for color work but B&W
> is much more of a personal choice of all the possibilities -- try out various blends for toning, burn/dodge i.e. darken/lighten
> areas of the print that you want that way.  Don't get hung up on the "best" curves & workflow.  "best" comes from
> you editing to your image so it looks like what you want.
> 
> Roy
> 
> 
>> On Mon, Nov 17, 2014 at 2:47 PM, Michael King drmrking@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:
>> 
>> 
>> Just so that people don't get confused, let's be clear that creating an ICC profile DOES NOT linearize anything. It simply gives you the ability to preview your print output on screen. BUT that also depends on you having an accurately profiled monitor to view it !! 
>> 
>> Any linearizing with this ICC approach is manual based on tweaking a PS curve and good luck with doing that accurately if your monitor is not high end and recently calibrated.
>> 
>> Mike
>> 
>>> On 17 November 2014 21:25, sanking@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:
>>>  
>>> Peter,
>>> 
>>> Or, you could use the method suggested by Roy Harrington for linearizing K7 inks where you create and apply an ICC custom file over the existing .quad file. In the case of the K7 inks this would probably be simpler for some than creating a new profile from scratch.
>>> 
>>> Sandy
>>> 
> 
> 
> -- 
> Roy Harrington
> roy@...
> www.harrington.com
>

Re: Basic Step tablet/UV light piesography question

2014-11-19 by sanking@...



The P2 Digital negative system that allows making both matte prints and digital negatives with the same ink set has a lot going for it. But the changes from curve generations is confusing, primarily in terms of which ink mixtures go in which slot. I think it will be useful to designate your curves for pt/pd by the UV density range. It is well known that the UV blocking of the K7 inks is much higher than visual light densitometer would indicate, so that the Methodology 3 curves that are designated 1.4, 1.6 and 1.8 actually measure much higher by UV reading.

It will also be useful to have the profiles deposit ink in a linear manner, not only for pt/pd but for nearly all of the alternative processes since nearly all of them are much more straight lined than silver.

Sandy




Re: Basic Step tablet/UV light piesography question

2014-11-19 by sanking@...

"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."

Another consideration is that you may want to provide one or two profiles with a relatively low density range as measured by UV. Many people experience trouble with high density range negatives that put down a lot of ink on the OHP. Inks don't seem to dry as fast on OHP materials like Pictorico as on paper substrates and this can cause printing artifacts like pizza wheel marks with some printers, and it is a problem with both K7 inks and Epson K3. It is an extremely frustrating problem if you happen to have one of these printers, and the only solution is to drop the DR of your negative and adjust the process, or dump the printer.

Sandy

Quad Tone Print Tool ceased to work with new OSX

2014-11-22 by Truman Prevatt

I recently installed the new OSX ,Yosemite.  Now my Quad Tone print tool does not work.


It list my QTR printer as a air print printer - QuadR3000@Truman I don't know if that was the same prior to Yosemite I didn't pay attention since it worked.


Any advice?


__
"If a politician found he had cannibals among his constituents, he would promise them missionaries for dinner."
H. L. Mencken


>
>

Re: Quad Tone Print Tool ceased to work with new OSX

2014-11-22 by David Swinnard

I can’t speak to your specific printer but when I updated to one of the final Yosemite betas and then to the final release I had no issues with Print Tool at all.  I’m running an old Epson R2400 over USB though. So Yosemite and Print Tool appear to play well together.

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