3800 - PDN or QTR?

[seans]

Hi all

I have spent weeks trying to calibrate my 3800 using QTR and just cannot get a good curve. I have gotten close and then tried a mild curve in PS and still cannot get it to work,

So - I wonder if I should go back to PDN as I originally did on my 2200. On my 2200 I had no trouble moving from PDN and creating a curve for QTR but just cant get it on the 3800.

Anyone have experience using PDN on the 3800 - I have read conflicting reports all over about it is ok and others that the inks do not serve PDN well.

Any coaching would be greatly appreciated

Thank you
Sean

 

[Platonumb]

Hello
I have the 3800 and have found printing in the colorized black and white
mode quite remarkable, only a slight curve and a 10% increase in ink density is needed to improve shadow density. The negatives are superior to my previous 2200 utilizing PDN, the prints have an improved smoothness and a more filmic look.
Truly
Platonumb

 

[donbga]

Hi all

I have spent weeks trying to calibrate my 3800 using QTR and just cannot get a good curve. I have gotten close and then tried a mild curve in PS and still cannot get it to work,

So - I wonder if I should go back to PDN as I originally did on my 2200. On my 2200 I had no trouble moving from PDN and creating a curve for QTR but just cant get it on the 3800.

Anyone have experience using PDN on the 3800 - I have read conflicting reports all over about it is ok and others that the inks do not serve PDN well.

Any coaching would be greatly appreciated

Thank you
Sean

Sean,

I can assure you that the 3800 works quite well with PDN. I don't have a 3800 but I have a friend here locally that makes very smooth negatives for palladium prints with his 3800 using PDN.

Don

 

[seans]

Hello
I have the 3800 and have found printing in the colorized black and white
mode quite remarkable, only a slight curve and a 10% increase in ink density is needed to improve shadow density.
Truly
Platonumb

Hi Platonumb
Thanks for the pointer to colorized BW - but I am not familiar with that approach.
Could you please take a moment to explain what that is - sounds great and if only takes a slight curve I am very interested.
Thank you
Sean

 

[seans]

Sean,

I can assure you that the 3800 works quite well with PDN. I don't have a 3800 but I have a friend here locally that makes very smooth negatives for palladium prints with his 3800 using PDN.

Don

Don,

Thank you for the reality check. I can proceed with confidence now.

Thanks
Sean

 

[Kerik]

Sean - So, the curve & info I sent you didn't work for you? If so, why not? It sounds like Platonumb is using a similar approach. Perhaps he means B&W RGB images?

 

[seans]

Sean - So, the curve & info I sent you didn't work for you? If so, why not? It sounds like Platonumb is using a similar approach. Perhaps he means B&W RGB images?

Kerik
I did use the curve you sent. It came out very dark. I did not want to bother you about it because it works for you and it must be my paper or some other element that is causing it to be so dark.

When the curve did not work I did not want to abuse the relationship and keep going back to the well - I assumed it was something in my process or paper. I dont like to keep bugging people that do this as a source of income = but I would be happy to pay for the expertise

I would really like it if you had a workshop where we could develop a curve together then I could bug you incessantly in the workshop, and yet another

Net - the curve was way to dark and so I went back on the QTR path and I am about 40 test prints later and no closer to success.

I have attached one image from my QTR 2200 neg - the good print - and then the print that came from the BW curve.

I would appreciate any help - I seem to be chasing my tail on this one.

Thanks for asking
Sean

 

[clay]

What specifically was f***ing up with the QTR approach? The density range, the curve? If you want to post the .qidf file, I could look at it. I have had very good luck with QTR now on three different printers, and the last one I nailed with only two test prints. It might help to see what you are doing.

Kerik
I did use the curve you sent. It came out very dark. I did not want to bother you about it because it works for you and it must be my paper or some other element that is causing it to be so dark.

When the curve did not work I did not want to abuse the relationship and keep going back to the well - I assumed it was something in my process or paper. I dont like to keep bugging people that do this as a source of income = but I would be happy to pay for the expertise

I would really like it if you had a workshop where we could develop a curve together then I could bug you incessantly in the workshop, and yet another

Net - the curve was way to dark and so I went back on the QTR path and I am about 40 test prints later and no closer to success.

I have attached one image from my QTR 2200 neg - the good print - and then the print that came from the BW curve.

I would appreciate any help - I seem to be chasing my tail on this one.

Thanks for asking
Sean

 

[seans]

What specifically was f***ing up with the QTR approach? The density range, the curve? If you want to post the .qidf file, I could look at it. I have had very good luck with QTR now on three different printers, and the last one I nailed with only two test prints. It might help to see what you are doing.

Clay - I will take you up on this offer!!!

Attached is the curve.

Basically - I originally had no problem getting range but then could never get the linearity needed in the midtones and kept getting compression in the shadows. I could not get the separation using only gamma or shadow in QTR

So I changed directions (from only using three blacks) and starting adding yellow. That gave me greater control in the shadows and I was able to get separation in the shadows - but now I could not get smoothness in the midtones.

So Here is the current curve for which I am trying to use a mid PS correction curve - for which I cannot get a good response.

Any thoughts would be greatly appreciated.

Sean

 

[clay]

I'm hoping Michael chimes in here with some thoughts too. But my first thought is that you probably want to add yellow only on the high end of the curve instead of the shadows where you have it now. Your copy curve now for yellow is LLK. I generally have it track the K curve, which gooses the density in the high values where you need it. I also might add small amounts of the other colors (probably ink limits around 3-4 % just for the heck of it, like so:
COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM=LK

you also can put in a Black boost statement to add density in the highlight areas of the negative, like so:

BOOST_K=40

Also, put in for your first pass through the following:

GRAY_CURVE="0;0 100;100"

Then print a step wedge and see where you are.

If you have a UV densitometer, and can post the negative UV transmission density values for each 5%, it would be pretty easy to create a rough starting curve from there. What I did after my first successful curve is just keep track of what print % value needs a particular UV density. The first pass linearization is cake with that information. The fine tuning then just takes some judicious tweaking.

Clay - I will take you up on this offer!!!

Attached is the curve.

Basically - I originally had no problem getting range but then could never get the linearity needed in the midtones and kept getting compression in the shadows. I could not get the separation using only gamma or shadow in QTR

So I changed directions (from only using three blacks) and starting adding yellow. That gave me greater control in the shadows and I was able to get separation in the shadows - but now I could not get smoothness in the midtones.

So Here is the current curve for which I am trying to use a mid PS correction curve - for which I cannot get a good response.

Any thoughts would be greatly appreciated.

Sean

 

[seans]

I'm hoping Michael chimes in here with some thoughts too. But my first thought is that you probably want to add yellow only on the high end of the curve instead of the shadows where you have it now. Your copy curve now for yellow is LLK. I generally have it track the K curve, which gooses the density in the high values where you need it. I also might add small amounts of the other colors (probably ink limits around 3-4 % just for the heck of it, like so:
COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM=LK

you also can put in a Black boost statement to add density in the highlight areas of the negative, like so:

BOOST_K=40

Also, put in for your first pass through the following:

GRAY_CURVE="0;0 100;100"

Then print a step wedge and see where you are.

If you have a UV densitometer, and can post the negative UV transmission density values for each 5%, it would be pretty easy to create a rough starting curve from there. What I did after my first successful curve is just keep track of what print % value needs a particular UV density. The first pass linearization is cake with that information. The fine tuning then just takes some judicious tweaking.

Alright - here is my starting point - I will keep you informed.

I do have a UV densitometer and a reflective so I can take any readings that will help you help me

Thanks Clay!

# QuadToneRIP curve descriptor file
#
# for ultrachrome k3 inks - these profiles will be using Matte as the black ink

PRINTER=Quad3800
CALIBRATION=NO
GRAPH_CURVE=YES

N_OF_INKS=8
DEFAULT_INK_LIMIT=35

LIMIT_K=
BOOST_K=40
LIMIT_C=4
LIMIT_M=4
LIMIT_Y=4
LIMIT_LC=4
LIMIT_LM=4
LIMIT_LK=
LIMIT_LLK=

#
# Describe Usage of each Ink: K,C,M,Y,LC,LM,LK
# All Inks of Printer must be listed
#

#
# Gray Partitioning Information
#
N_OF_GRAY_PARTS=3
GRAY_INK_1=K
GRAY_VAL_1=100

GRAY_INK_2=LK
GRAY_VAL_2=33

GRAY_INK_3=LLK
GRAY_VAL_3=12

GRAY_INK_4=
GRAY_VAL_4=

GRAY_HIGHLIGHT=0
GRAY_SHADOW=0

GRAY_GAMMA=1
GRAY_CURVE="0;0 100;100"

COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM=LK

 

[seans]

I'm hoping Michael chimes in here with some thoughts too. But my first thought is that you probably want to add yellow only on the high end of the curve instead of the shadows where you have it now. Your copy curve now for yellow is LLK. I generally have it track the K curve, which gooses the density in the high values where you need it. I also might add small amounts of the other colors (probably ink limits around 3-4 % just for the heck of it, like so:
COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM=LK

you also can put in a Black boost statement to add density in the highlight areas of the negative, like so:

BOOST_K=40

Also, put in for your first pass through the following:

GRAY_CURVE="0;0 100;100"

Then print a step wedge and see where you are.

If you have a UV densitometer, and can post the negative UV transmission density values for each 5%, it would be pretty easy to create a rough starting curve from there. What I did after my first successful curve is just keep track of what print % value needs a particular UV density. The first pass linearization is cake with that information. The fine tuning then just takes some judicious tweaking.

OK Clay - here we go...

Attached is one image of 4 screen shots for densitometer readings of a 101 square grid

In the center of the image is my starting curve txt file - in all images the red line will be this curve

On all the images the green curve is the curve that results from the changes stated in the green text.

Based on this what I think is....

Curve 4 gets me the highlights close to what I would like - and since I have always found those the hardest to correct I would start to create a grey curve based on curve 4

On the other hand - Curve 2 is the most balanced - a gentle S curve that could use mild correction - in PS or QTR?

So it is at this stage I look for expert opinion on where to go next.

My basic process is as follows -

Fabriano Artistico Extra White Hot Press that has been acidified using 4% oxalic acid for 15 minutes
I humidify for 20 minutes from 50-53%
Then paint, dry for 20 minutes
Expose in UV light box for 7.5 minutes
Develop 3 minutes in 105 degree Pot Ox

I hope this is enough info for you to help me

Thanks again to any and all that can provide advice
Sean


PS I just posted the image and it may be too small to read the print so here are the curves

Start Curve in red
N_OF_INKS=8
DEFAULT_INK_LIMIT=35

LIMIT_K=
BOOST_K=40
LIMIT_C=4
LIMIT_M=4
LIMIT_Y=4
LIMIT_LC=4
LIMIT_LM=4
LIMIT_LK=
LIMIT_LLK=

#
# Describe Usage of each Ink: K,C,M,Y,LC,LM,LK
# All Inks of Printer must be listed
#

#
# Gray Partitioning Information
#
N_OF_GRAY_PARTS=3
GRAY_INK_1=K
GRAY_VAL_1=100

GRAY_INK_2=LK
GRAY_VAL_2=33

GRAY_INK_3=LLK
GRAY_VAL_3=12

GRAY_INK_4=
GRAY_VAL_4=

GRAY_HIGHLIGHT=0
GRAY_SHADOW=0

GRAY_GAMMA=1
GRAY_CURVE="0;0 100;100"

COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM-LK

Curve 1 - Added grey shadow of 1

Curve 2 - Grey shadow to 4

Curve 3 - Grey Shadow to 1, Ink levels Default at 35 and K Boost reduced to 38

Curve 4 - Grey Shadow to 2 and Default Grey to 30 and K Boost to 36

 

[clay]

Well, any of these could be corrected with the gray curve in QTR. One thing I need to understand - the values on your curves are the printed 51 step tablet values, correct? The resolution of the jpeg posted is not high enough to read any detail, unfortunately. Is there any way you can post (or send) the UV transmission density values for the step tablet? IOW, not the print's values but the negative's values.

One of the difficult things to wrap your head around with QTR is that the correction curve is for the ink on the negative, not the final printed values. So if you want 'whiter whites', that means more ink (on the negative) not less. What I have ended up doing is keeping an ideal (for my ideal palladium print) set of 51 step negative UV transmission density values on a spreadsheet. That makes it relatively easy to create a simple adjustment curve for QTR. For instance, if my 'ideal' UV density (for the negative, again) for the 20% print step (a negative value of 80%) is 2.2, and the first pass through shows that 2.2 pops up at the 30% (70% negative) step, I would have a correction pair that maps the 80% desired negative density to the 70% ink value. I to this with all the values and make a smooth adjustment curve using and Excel spreadsheet, and paste the correction curve into the correction curve area of the QTR file.

OK Clay - here we go...

Attached is one image of 4 screen shots for densitometer readings of a 101 square grid

In the center of the image is my starting curve txt file - in all images the red line will be this curve

On all the images the green curve is the curve that results from the changes stated in the green text.

Based on this what I think is....

Curve 4 gets me the highlights close to what I would like - and since I have always found those the hardest to correct I would start to create a grey curve based on curve 4

On the other hand - Curve 2 is the most balanced - a gentle S curve that could use mild correction - in PS or QTR?

So it is at this stage I look for expert opinion on where to go next.

My basic process is as follows -

Fabriano Artistico Extra White Hot Press that has been acidified using 4% oxalic acid for 15 minutes
I humidify for 20 minutes from 50-53%
Then paint, dry for 20 minutes
Expose in UV light box for 7.5 minutes
Develop 3 minutes in 105 degree Pot Ox

I hope this is enough info for you to help me

Thanks again to any and all that can provide advice
Sean


PS I just posted the image and it may be too small to read the print so here are the curves

Start Curve in red
N_OF_INKS=8
DEFAULT_INK_LIMIT=35

LIMIT_K=
BOOST_K=40
LIMIT_C=4
LIMIT_M=4
LIMIT_Y=4
LIMIT_LC=4
LIMIT_LM=4
LIMIT_LK=
LIMIT_LLK=

#
# Describe Usage of each Ink: K,C,M,Y,LC,LM,LK
# All Inks of Printer must be listed
#

#
# Gray Partitioning Information
#
N_OF_GRAY_PARTS=3
GRAY_INK_1=K
GRAY_VAL_1=100

GRAY_INK_2=LK
GRAY_VAL_2=33

GRAY_INK_3=LLK
GRAY_VAL_3=12

GRAY_INK_4=
GRAY_VAL_4=

GRAY_HIGHLIGHT=0
GRAY_SHADOW=0

GRAY_GAMMA=1
GRAY_CURVE="0;0 100;100"

COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM-LK

Curve 1 - Added grey shadow of 1

Curve 2 - Grey shadow to 4

Curve 3 - Grey Shadow to 1, Ink levels Default at 35 and K Boost reduced to 38

Curve 4 - Grey Shadow to 2 and Default Grey to 30 and K Boost to 36

 

[seans]

Well, any of these could be corrected with the gray curve in QTR. One thing I need to understand - the values on your curves are the printed 51 step tablet values, correct? The resolution of the jpeg posted is not high enough to read any detail, unfortunately. Is there any way you can post (or send) the UV transmission density values for the step tablet? IOW, not the print's values but the negative's values.

Clay
Since I had expereince with PDN I am using the 101 step tablet from PDN not a 51 step

Attached is a spreadsheet with all the values -

Step Reading of image in PS

UV Reading of neg

Reflection reading of print

Thank you for reviewing and advising!
Sean

 

[Kerik]

Man, you guys are making my head hurt. I need to get going with QTR at some point, but this is all Greek to me. OK, well Turkish... I'm happy with the approach I'm using, but it seems QTR is perhaps the ultimate way to go.

 

[clay]

I goofed and hit carriage return before I was finished typing. IOW, see below.

 

[clay]

I finally had time to look at the numbers you posted on the spreadsheet. What I think may be some of the problem is that you are not getting enough maximum density on your negative. On all of my negatives, I am shooting for a max UV logD transmission density 2.8-2.9. Your maximum density is 2.38 on curve 2. So the first thing I would do is pump in a little more ink. The easiest way for you to do this is to change the ink limit on your yellow ink from 4 to about 12. You can also increase the default ink limit to something like 37-40. This will give you a little more running room.

Once that is done, even before printing a test strip, measure the UV densities for every 2% for the top and bottom 20% and 10% in between, and compare them to the values on the attached pdf file.

You can then use this to make a rough correction curve right off the bat. For instance, if 70% on your negative (30% on print) shows a UV value of 1.23, then it needs to actually be 1.79, so you need to find the correct percentage/density pair to give you that. Let's say that the 'correct' 1.79 density occurs at 80% (20% print value). So one correction pair would be:

70;80

You do this with all the values and put them in a spreadsheet with a graph attached and make sure it is all a nice smooth S curve with no jags and bumps. And this will get you 90% of the way there in one shot. The rest is looking at test tablets that you print and making judgments like. "I think the upper quarter-tones are too light, so I am going to add a little less ink density to the negative , therefore I will change the pair 70;80 to 70;77. Naturally, this change will cascade to all the adjacent points and require you to adjust them to maintain the smooth curve.

I also want to point out that the 'ideal curve' values I have posted here are the ones that work for me. I have a calibrated monitor, work in Gamma 2.2, and print all my palladium with no restrainer. But, I also tend to like my prints a little more 'airy' in the high values than some people might. All these factors mean that these numbers really only represent a shortcut to the starting point for any particular person printing in palladium. You will have to look at a step tablet and some sample prints to decide if they work for you or that they need tweaking.

Clay
Since I had expereince with PDN I am using the 101 step tablet from PDN not a 51 step

Attached is a spreadsheet with all the values -

Step Reading of image in PS

UV Reading of neg

Reflection reading of print

Thank you for reviewing and advising!
Sean

 

[Carl Radford]

Watching this thread carefully before going down this route but do not have a densitometer - does one need a transmission or reflection densitometer or both?

Cheers, Carl

 

[clay]

Carl, I would just wait for the dust to settle here. If we can get Sean a good profile built, you could do the rest with your eyeballs after cadging the profile.I am pretty confident we can get Sean a working profile in a few tries.

Watching this thread carefully before going down this route but do not have a densitometer - does one need a transmission or reflection densitometer or both?

Cheers, Carl

 

[Carl Radford]

Sounds good to me...

happy to send test neg, print etc just to get verification on what I am producing. Hopefully I will get my monitor calibrated soon - I think I know someone that has one which will help too.

All the very best, Carl

Carl, I would just wait for the dust to settle here. If we can get Sean a good profile built, you could do the rest with your eyeballs after cadging the profile.I am pretty confident we can get Sean a working profile in a few tries.

 

[seans]

... But, I also tend to like my prints a little more 'airy' in the high values than some people might. All these factors mean that these numbers really only represent a shortcut to the starting point for any particular person printing in palladium. You will have to look at a step tablet and some sample prints to decide if they work for you or that they need tweaking.

OK Clay, (ya big stud) I say that VERY appreciatively because you have gotten me further in two negatives than my last 50!

Attached is a spreadsheet of where I am.

Net - I did the base neg - measured and then as you said found curve points to create a new neg that should deliver ideal densities.

Well - it worked like a charm! The corrected values ended up almost EXACTLY where they were supposed to.

Now - I just to get them to the right place... in other words the print is too light.

So.. to help me and those that are following this (as this is turning out to one awesome tutorial)...

I am using gamma 1.8
Matte ink
Fab Hot Press

So between paper and ink combo if I need to shift some ink AWAY from the dark side of the neg should I just start with an increase in Gray Shadow?

Thank you again Clay - this is a HUGE help!
Sean

 

[clay]

I think I would just modify the curve points a little bit. You say the print is too light. And you're using matte inks. Another person I helped through this process was using matte inks also, and it made a surprising difference. Anyway, it looks like you are close. What I do now is put the correction curve itself in a spreadsheet, and then start tweaking that so the curve is smooth.

Here is a spreadsheet with your gray curve corrections, and then the next column contains what I would do if everything is too light. Right now, you are mapping input 30% to output 48%. It is too light, ergo, you have too much ink. So I picked a point in the middle - around 70%. You have 70% mapping to 70% now. You want less ink - lets in more light and makes the print darker. So I changed the output from 70% to 66%. And then I fiddled around with the other values to give a nice smooth continuous curve with approximately the same inflections.

The third set of columns is a free-try-it-yourself version. And the last one shows what I would do if I thought the shadow contrast needed a little boost. Notice how the light blue curve is steeper in the lighter areas (shadows on the print) This is basically how you will approach tweaking the gray curve value. Just play around with those numbers and make a nice smooth curve to do what you want. Then transfer the pairs to the gray curve box in the QTR profile. That's it.

I think you have managed to snatch the pebble from my hand, grasshopper.

OK Clay, (ya big stud) I say that VERY appreciatively because you have gotten me further in two negatives than my last 50!

Attached is a spreadsheet of where I am.

Net - I did the base neg - measured and then as you said found curve points to create a new neg that should deliver ideal densities.

Well - it worked like a charm! The corrected values ended up almost EXACTLY where they were supposed to.

Now - I just to get them to the right place... in other words the print is too light.

So.. to help me and those that are following this (as this is turning out to one awesome tutorial)...

I am using gamma 1.8
Matte ink
Fab Hot Press

So between paper and ink combo if I need to shift some ink AWAY from the dark side of the neg should I just start with an increase in Gray Shadow?

Thank you again Clay - this is a HUGE help!
Sean

 

[seans]

Success - thank you Sensi!!

I think I would just modify the curve points a little bit. You say the print is too light. ...

Here is a spreadsheet with your gray curve corrections, and then the next column contains what I would do if everything is too light. ..
...Just play around with those numbers and make a nice smooth curve to do what you want. Then transfer the pairs to the gray curve box in the QTR profile. That's it.

I think you have managed to snatch the pebble from my hand, grasshopper.

Grasshopper happily rubbing legs together right now.... OK maybe that is not such a pretty picture but anyway - SUCCESS!

Attached is my final spreadsheet. It shows that the curve is not exactly perfect - but after a few prints I notices that it is so close that I will always be tweaking any print anyway with a minor PS curve so it gets me exactly where I need to be for a very efficient starting point of any print.

Note the following for those of you following this thread -

This turned out to be a great way for me to create a curve by using UV density - as that was the key for me to understand how to control the curve in QTR. Once you have a simple base curve adjusted for black and white points with a curve place holder of 0;0 and 100;100 - then the UV density of that curves points will guide the way.

I then learned that Ideal's are not always Ideal for my paper/ink combo - as Clay said it is a great start and then you dial it in.

Dialing in was very easy once I understood that the Base Curve you create with it's UV Density is always the curve to return to when writing a curve in QTR - because that is the one that tells you what step you need to target as the correct step.

I read what I am writing here and it seems confusing but if anyone would like it - I am happy to break down what I did step by step with examples from both the spreadsheet and prints to show how I got from A to Z with Clays help.

Let me know and I will be glad to create and post.

But.... this turned out to be SOOOOO much easier than how I started and in fact took only a couple of days once I cracked the nut of just how easy it is to control the QTR curve when you know what levers to pull.

Again - thank you Sensi (Clay) grasshopper very happy!

Sean

 

[BillSchwab]

Again - thank you Sensi (Clay) grasshopper very happy!

Clay is a very fine teacher. He coached me through this as well and I too am very happy with the QTR diginegs I am now making.

Bill

 

[Kerik]

I read what I am writing here and it seems confusing but if anyone would like it - I am happy to break down what I did step by step with examples from both the spreadsheet and prints to show how I got from A to Z with Clays help.

Let me know and I will be glad to create and post.

Sean,

Waiting with baited breath (and trying to get the picture of you rubbing your legs together out of my head). Please, please, PLEASE???

Thanks to Sensi Clay and Grasshopper!