AZO Print from Digital Negative

[sanking]

I am attaching a small .jpeg of an 8X10 print I made on AZO 2 from a digital negative. The negative was made with an Epson 3800 and a QTR profile that was originally created by Ron Reeder, and then adapted by me.

This is by far the best results I have ever been able to get on a silver paper. The grain is very fine, about like what you would get in enlarging a 4X5 medium speed B&W film to 16X20, and sharpness is very impressive. There are no printer artifacts that I am able to see.

I printed the negative with an Amergraph ULF-28 with three (3) .9 ND filters in the filter drawer to attenuate the light. Exposure was 25 units, where one unit is about one second. I also printed the negative with a 13 watt spiral BLB tube, placed at 36" from the printing frame, which is a very inexpensive and efficient light source for AZO.

Development was in Ansco 130 diluted 1:2 at 72F for 2.5 minutes. The print was selenium toned 1:100 for three minutes.

I though this was a nice find just for walking through an airport terminal


Sandy King

 

[Ron-san]

I am attaching a small .jpeg of an 8X10 print I made on AZO 2 from a digital negative. The negative was made with an Epson 3800 and a QTR profile that was originally created by Ron Reeder, and then adapted by me.

Sandy King

To the Hybrid Community-- The QTR profile Sandy used to make this print (plus a separate profile for making Cyanotypes) will be posted on my website, www.ronreeder.com, as soon as I can get it done. Enjoy, Ron Reeder

 

[keithwms]

Ah, very nice, looks good Sandy.

 

[John W]

I printed the negative with an Amergraph ULF-28 with three (3) .9 ND filters in the filter drawer to attenuate the light.

That's interesting; I'd seen ads for the Amergraph units, but hadn't appreciated this feature. Has anyone worked out an attenuation scheme for the Nuarc flip-top units, perhaps using gels?

Also, is there a current supply for Azo paper? All I've found on a search is Michael Smith and Paula Chamlee's site, but it's not clear whether there's any stock available (vs. the preorders on the new supplier.)

 

[sanking]

The ULF-28 has a filter drawer underneath the light that allows placing large ND filters. This is an optional feature. Another option is a small tungsten light that allows printing with regular silver papers.

So you can use the ULLF-28 with slow silver chloride papers (AZ0) with just the filter drawer and three .9 ND filters that attenuates the light of the 1200 watt Xenon light, or you can use the unit with the small tungsten light for printing on regular silver papers.

There is no current source for AZO papers but the paper has very long shelf life (decades) and there is still quite a bit of old paper out there, though it is a bit pricey.

Sandy King

That's interesting; I'd seen ads for the Amergraph units, but hadn't appreciated this feature. Has anyone worked out an attenuation scheme for the Nuarc flip-top units, perhaps using gels?

Also, is there a current supply for Azo paper? All I've found on a search is Michael Smith and Paula Chamlee's site, but it's not clear whether there's any stock available (vs. the preorders on the new supplier.)

 

[rogein]

To the Hybrid Community-- The QTR profile Sandy used to make this print (plus a separate profile for making Cyanotypes) will be posted on my website, www.ronreeder.com, as soon as I can get it done. Enjoy, Ron Reeder

Thanks Ron!

 

[menglert]

Sandy,

Did you use Pictorico OHP or white film? Also, do you believe the smoothness was from the Epson 3800, or rather the method of using QTR?

I would like to dive back into printer in silver gelatin again, time allowing. My darkroom has been down since I moved almost a year ago and work hasn't allowed me the freetime to get back into things.

Thanks,
Martin

 

[sanking]

Martin,

I used regular Pictorico, not the white film.

I can not really say whether the smoothness is from the Epson 3800, or from the use of QTR with the 3800, or from the specific profile that was used. Or perhaps it was the combination of all three?

It seems to me that there are specific combinations of RGB values that one could use, say in printing from the Epson driver, that would maximize smoothness for a specific process. The issue is that all of the processes have different spectral sensitivity requirements, as well as transmission Dmax requirements to give paper white.

Sandy King

Sandy,

Did you use Pictorico OHP or white film? Also, do you believe the smoothness was from the Epson 3800, or rather the method of using QTR?

I would like to dive back into printer in silver gelatin again, time allowing. My darkroom has been down since I moved almost a year ago and work hasn't allowed me the freetime to get back into things.

Thanks,
Martin

 

[Ben Altman]

I can not really say whether the smoothness is from the Epson 3800, or from the use of QTR with the 3800, or from the specific profile that was used. Or perhaps it was the combination of all three?

It seems to me that there are specific combinations of RGB values that one could use, say in printing from the Epson driver, that would maximize smoothness for a specific process. The issue is that all of the processes have different spectral sensitivity requirements, as well as transmission Dmax requirements to give paper white.

Sandy King

Hi Sandy,

QTR uses its own screening algorithms, so a simple-minded guess is that the sophisticated algorithm that Epson developed for the 3800 is not a factor in the smoothness you achieved. So that would suggest that the particular combination of inks and profile is what is making it smooth. Is this a K/LK/LLK-only profile?

It would not be too hard to use the QTR Calibration routine to examine each ink by itself, exposed onto any particular material, to see which inks are smooth and at which densities. It might be necessary to figure out how to print bigger (in area) step-wedges to see them well, though. Developing a profile from that information is probably more challenging, but it is possible.

Hopefully I'll have my new darkroom in operation eventually, too, and will be able to finish the profile-development work I was doing last year... Martin, I feel your pain!

Ben

 

[sanking]

Ben,

First, all of the inks of the 3800 are used in the AZO profile, with the exception of LLB which had little or no blocking for AZO.

The information in your second paragraph is precisely where I have a question. I have printed the calibration routine and what is readily apparent is the blocking density of each of the inks, and their absolute smoothness. What I am not able to figure is how the smoothness for an individual ink relates to a profile where several of the inks are used in combination.

Sandy King

Hi Sandy,

QTR uses its own screening algorithms, so a simple-minded guess is that the sophisticated algorithm that Epson developed for the 3800 is not a factor in the smoothness you achieved. So that would suggest that the particular combination of inks and profile is what is making it smooth. Is this a K/LK/LLK-only profile?

It would not be too hard to use the QTR Calibration routine to examine each ink by itself, exposed onto any particular material, to see which inks are smooth and at which densities. It might be necessary to figure out how to print bigger (in area) step-wedges to see them well, though. Developing a profile from that information is probably more challenging, but it is possible.

Hopefully I'll have my new darkroom in operation eventually, too, and will be able to finish the profile-development work I was doing last year... Martin, I feel your pain!

Ben

 

[Ben Altman]

Hi Sandy,

Given the zillions of possible combinations of seven inks to make even a step-wedge, it's clearly beyond us basement tinkerers to explore all the possibilities. My suggestion is simpler - to assume that one would do well to build a profile using each ink only at those densities where that ink looks smooth by itself.

To go a little farther, though, it seems to me sensible that if one uses lots of nozzles for a given density, rather than just a few, the result will be smoother. Also, it seems that one should avoid creating a density out of a screen of inks with widely disparate blocking - that would average to a certain density but show unevenness at the dot level.
So putting those ideas together, one would build a profile that uses several inks of closely-related blocking for each density, and transition smoothly from using the least-dense to most-dense inks along the length of the profile.
A profile built this way only uses each ink at low densities, so the bottom ends of each ink's calibration profile are the only parts that relevant.
From what I've read of Ron Reeder's approach, I think his profiles pretty much follow these principles. I tried to develop a method that gives more particular control of each ink, which works, but I'm not sure how much is gained in practice
The results I got with an 1800 and K3 inks on POP Pd were pretty good. I haven't tried a silver process yet, which would be the real test of smoothness.
When I get things a little straighter around here I'd be interested to try writing such a profile, using the spreadsheet I've developed.

For Azo, do you think the UV or the optical density of the digital negative is more informative?

Best, Ben

Ben,

First, all of the inks of the 3800 are used in the AZO profile, with the exception of LLB which had little or no blocking for AZO.

The information in your second paragraph is precisely where I have a question. I have printed the calibration routine and what is readily apparent is the blocking density of each of the inks, and their absolute smoothness. What I am not able to figure is how the smoothness for an individual ink relates to a profile where several of the inks are used in combination.

Sandy King

 

[sanking]

Thanks for your comments.

AS for the question about AZO, the answer depends on whether you are printing with a UV light source or with a visual (tungsten) type light source. AZO has considerable sensitivity in both areas, and the best blocking colors are different for the different wavelengths.

I decided to base the profile on UV light since I have a ULF-28 platemaker with vacuum frame and integrator to print with, as well as a 13 watt spiral fluorescent tube that is also connected to an integrator. The 13 watt UV tube is very efficient as it puts out about as much useful radiation as a 90 watt flood.

Sandy

 

[Ron-san]

Hi Sandy,


From what I've read of Ron Reeder's approach, I think his profiles pretty much follow these principles. I tried to develop a method that gives more particular control of each ink, which works, but I'm not sure how much is gained in practice

Best, Ben

Ben
In writing profiles I assume that tonal smoothness is achieved by filling in the holes around each ink dot as completely as possible (this seems to be your thinking as well). If this is true, then the sweet spot for each individual ink is when it is printing at close to 100% and completely covering the OHP. Unfortunately, I do not know how to write a profile that keeps all the inks printing at that level, especially for the Epson ink sets which vary rather wildly in blocking power from one ink to another. I once tried, for a palladium profile, to balance all the Epson 4000 inks so that they were used at identical UV blocking power -- and ended up with a sheet of OHP that was dripping wet.
So, for the AZO profile, we used the following approach. First I printed out a QTR ink calibration test which displays each of the inks, printing in patches of increasing density from 0 to 100% of the machine ink limit. I then sent this sheet to Sandy who contact printed it onto a sheet of AZO2 paper. He scanned the contact print and sent the scan back to me. From the contact print I could rank all the inks of the 3800 in order of their ability to block exposure to AZO2 paper.
Three conclusions seemed clear. First, the LM ink has almost no blocking power. Using it would only add to liquid load on the OHP so I turned it off as being useless for AZO2. Second, of the dark inks, mK and Y were the best blockers and of close to equal strength, while C and M were less good. So I kept the ink limits for mK and Y the same and increased the limits for C and M proportionately to try and bring all the dark inks somewhat into the same range of blocking power (not completely able to do this, but maybe it helped). Finally, LK LC and LLK were chosen as the light inks. The LC and LLK limits were chosen to be double the LK limit, again in an attempt to achieve some parity in the blocking power of the three light inks.
Oh yes, this was set up as a two part gray system, so the C, M, and Y inks were set to follow the distribution of the mK ink. And the LC and LLK inks were set to follow the distribution of the LK ink.

That was the logic behind the profile. Ink limits were chosen by just eyeballing the AZO contact sheet but I kind of doubt that trying to be more rigorously mathematical would buy you more tonal smoothness because the actual densities of the individual inks do not allow you to arrange them in strictly equal blocking power -- without overloading the OHP.
I am amazed that this profile works as well as it seems to. My own guess is that it is due to both the smooth-printing characteristics of the Epson 3800 print head with a bit of help from partially balanced ink usage. But rather than analyze it further, I say, Hallelujah! Use it.

And, by the way, a QTR profile for printing on silver gelatin paper (MultigradeIV) is also on my website and it works pretty good also.

Cheers, Ron Reeder

 

[Ben Altman]

Hi Ron,

Thanks for the detailed description of your methods. It does sound as if we are on the same page as far as objectives. I'm always wary of black-box things where I can't see the wheels turning for myself, so my approach is to ditch all the "conveniences" of QTR and "simply" build a curve for each ink. Sample QTR profile below.

The spreadsheet I have put together gives me graphs of the total ink volume and a reasonably accurate (more work needed on this) numerical and graphical estimate of the total density profile, starting from densities read from QTR calibration strips. Each graph also shows the individual ink curves. The neat thing about those Excel graphs is that I can grab a point on any curve and move it, and the spreadsheet recalculates everything. It also shows me what the curve I started with looks like, for comparison. The sheet output is formatted text that I can paste right into a profile. I'd post some example graphs, but the site doesn't seem to accept .xls files.

This profile (for Pd) uses one yellow channel, two channels with a 50/50 mix of yellow and light black, three light black channels, and two LLK channels, all K3. Next time I work on this, I'll try loading matte black instead of yellow, and photo black istead of the Y/LK mix. From comments I've read, probably yours, that might be a workable range of inks for UV.

Do you find the 3800 negs a lot smoother than the 4000 negs? I have an old 7600 I'm planning to try.

Best, Ben


# QuadToneRIP curve descriptor file
#
# for R1800 with Ben's K3 inks

PRINTER=QuadR1800
CURVE_NAME=OHP-1Y2YLK3LK2LLK-70416-12.txt
CALIBRATION=NO
GRAPH_CURVE=YES

#
N_OF_INKS=8
DEFAULT_INK_LIMIT=100

#
# Describe Usage of each Ink: K,C,M,Y,LC,LM,LK,GL
# All Inks of Printer must be listed
#
# Unused Inks
N_OF_UNUSED=0

CURVE_MK="0;0 5;1.94 10;2.85 15;4.42 20;6.26 25;7.81 30;8.7 35;9.29 40;10.05 45;10.95 50;11.91 55;13.10 60;14.40 65;15.87 70;17.67 75;19.66 80;22.32 85;24.04 90;26.62 95;28.16 100;33.76"
CURVE_PK="0;0 5;1.94 10;2.85 15;4.42 20;6.26 25;7.81 30;8.7 35;9.2 40;10.05 45;10.95 50;11.91 55;13.10 60;14.40 65;15.87 70;17.67 75;19.66 80;22.32 85;24.042 90;26.62 95;28.16 100;33.76"
CURVE_C="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.0625 45;19.92 50;21.92 55;22.62 60;22.9 65;22.1 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_B="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.06 45;19.92 50;21.92 55;22.624 60;22.9 65;22.1142857142857 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_M="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.06 45;19.92 50;21.9285714285714 55;22.624 60;22.9 65;22.1142857142857 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_R="0;0 5;24.80 10;33.73 15;32.5 20;28.9 25;23.83 30;20 35;15.6 40;12 45;8.38 50;4.6 55;2.25 60;0.9 65;0.5 70;0 75;0 80;0 85;0 90;0 95;0 100;0"
CURVE_GL="0;0 5;24.8017981147368 10;33.73 15;32.5 20;28.9 25;23.83 30;20 35;15.6 40;12 45;8.38 50;4.6 55;2.25 60;0.9 65;0.5 70;0 75;0 80;0 85;0 90;0 95;0 100;0"
CURVE_Y="0;0 5;0 10;0 15;0 20;0 25;0 30;0 35;0 40;0 45;0 50;0 55;0.24 60;0.46 65;1.17 70;2.09 75;2.56 80;2.98 85;3.51 90;3.795 95;4.32 100;6.39"


The strange curve names reflect the original inkset names of the R1800. MK and PK are the Y/LK channels, C,B,M are the LK channels, R and GL are the LLK channels, and Y=Y.

 

[Ron-san]

Hi Ron,

Thanks for the detailed description of your methods. It does sound as if we are on the same page as far as objectives. I'm always wary of black-box things where I can't see the wheels turning for myself, so my approach is to ditch all the "conveniences" of QTR and "simply" build a curve for each ink. Sample QTR profile below.

The spreadsheet I have put together gives me graphs of the total ink volume and a reasonably accurate (more work needed on this) numerical and graphical estimate of the total density profile, starting from densities read from QTR calibration strips. Each graph also shows the individual ink curves. The neat thing about those Excel graphs is that I can grab a point on any curve and move it, and the spreadsheet recalculates everything. It also shows me what the curve I started with looks like, for comparison. The sheet output is formatted text that I can paste right into a profile. I'd post some example graphs, but the site doesn't seem to accept .xls files.

This profile (for Pd) uses one yellow channel, two channels with a 50/50 mix of yellow and light black, three light black channels, and two LLK channels, all K3. Next time I work on this, I'll try loading matte black instead of yellow, and photo black istead of the Y/LK mix. From comments I've read, probably yours, that might be a workable range of inks for UV.

Do you find the 3800 negs a lot smoother than the 4000 negs? I have an old 7600 I'm planning to try.

Best, Ben


# QuadToneRIP curve descriptor file
#
# for R1800 with Ben's K3 inks

PRINTER=QuadR1800
CURVE_NAME=OHP-1Y2YLK3LK2LLK-70416-12.txt
CALIBRATION=NO
GRAPH_CURVE=YES

#
N_OF_INKS=8
DEFAULT_INK_LIMIT=100

#
# Describe Usage of each Ink: K,C,M,Y,LC,LM,LK,GL
# All Inks of Printer must be listed
#
# Unused Inks
N_OF_UNUSED=0

CURVE_MK="0;0 5;1.94 10;2.85 15;4.42 20;6.26 25;7.81 30;8.7 35;9.29 40;10.05 45;10.95 50;11.91 55;13.10 60;14.40 65;15.87 70;17.67 75;19.66 80;22.32 85;24.04 90;26.62 95;28.16 100;33.76"
CURVE_PK="0;0 5;1.94 10;2.85 15;4.42 20;6.26 25;7.81 30;8.7 35;9.2 40;10.05 45;10.95 50;11.91 55;13.10 60;14.40 65;15.87 70;17.67 75;19.66 80;22.32 85;24.042 90;26.62 95;28.16 100;33.76"
CURVE_C="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.0625 45;19.92 50;21.92 55;22.62 60;22.9 65;22.1 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_B="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.06 45;19.92 50;21.92 55;22.624 60;22.9 65;22.1142857142857 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_M="0;0 5;4.43 10;7.33 15;8.7 20;10.04 25;11.51 30;13.66 35;15.62 40;18.06 45;19.92 50;21.9285714285714 55;22.624 60;22.9 65;22.1142857142857 70;20.6 75;18.8 80;16.9 85;15.6 90;13.7 95;12.4 100;7.3"
CURVE_R="0;0 5;24.80 10;33.73 15;32.5 20;28.9 25;23.83 30;20 35;15.6 40;12 45;8.38 50;4.6 55;2.25 60;0.9 65;0.5 70;0 75;0 80;0 85;0 90;0 95;0 100;0"
CURVE_GL="0;0 5;24.8017981147368 10;33.73 15;32.5 20;28.9 25;23.83 30;20 35;15.6 40;12 45;8.38 50;4.6 55;2.25 60;0.9 65;0.5 70;0 75;0 80;0 85;0 90;0 95;0 100;0"
CURVE_Y="0;0 5;0 10;0 15;0 20;0 25;0 30;0 35;0 40;0 45;0 50;0 55;0.24 60;0.46 65;1.17 70;2.09 75;2.56 80;2.98 85;3.51 90;3.795 95;4.32 100;6.39"


The strange curve names reflect the original inkset names of the R1800. MK and PK are the Y/LK channels, C,B,M are the LK channels, R and GL are the LLK channels, and Y=Y.

Ben-- Seems clear that you understand and use QTR at a much deeper level than I do. I did not even know it was possible to do all the things you are doing in the profile you posted. If you will bear with me, I would love to educate myself. I have so many questions I hardly know where to start.

For one thing, I don't understand the ink/channel assignments. What does it mean to have a Y/LK channel? How do you have more than one LK channel (ie, C, B, M)?

If I understand correctly, you are not using any of Roy's black boxes to control where light inks leave off and dark inks begin. You do it all by hand, it looks like. Why is this an advantage?

I do not see the correspondence between the profile as written and the ink curves that you sent separately as a graph. The profile has eight ink curves while the graph only has 4 ink curves (plus some summation curves). What am I missing?

That is enough questions to get started.

My impression is that the 3800 is much smoother in printing than the 4000. In addition, the my 4000 has a noxious banding pattern with a periodicity of about 1.5-2 inches (roughly the size of the print head?) that shows up in clear sky and is thankfully absent from the3800. Plus, the 3800 inkset prints beautifully on the new baryta coated papers (when I want to make pseudo silver gelatin prints) and the 4000 inset bronzes badly. But, I still use the 4000 at lot since for much palladium printing it still looks very good and this way I have two printers to play with.

If you have the patience I would really like to understand how you are using QTR.

Cheers, Ron Reeder

 

[Ben Altman]

Hi Ron,

If I confused you I'm sure no-one else has a clue what I'm on about... if anyone else is even trying at this point.

Actually, I don't want to have a deep understanding of all those black boxes - that's why I don't use them. When I had one of those fancy Nikons I used to shoot everything on manual with the spot-meter... But also, it seemed like a good thing to be able to see exactly what's going on. Not sure I realized how much work I was letting myself in for. But my spreadsheet takes a lot of the "by hand" out of it.

Anyway, to try to be more clear... My R1800 has 8 ink channels. I bought empty after-market cartridges and filled one with yellow ink, three with light black, two with light-light black and two with a 50/50 mixture of yellow and light black, what I called "Y/LK". So it's a bit like one of those graduated inksets for regular B&W printing, in this case with 4 different inks spread over 8 channels. The mixing of the yellow/light black is a complication; I'm hoping that photo black will make a good substitute next time I try this.

If you look at the numbers in the profile in my last message you'll see that the curves for all cartridges with the same ink are identical. That's why only one of each shows on the plot I sent you by e-mail. I could use the "copy curve" function to build the profile in QTR, I guess, but the spreadsheet just duplicates the numbers for me, so I don't need to.

Hope that helps!

Ben

 

[sanking]

Ben,

Just wondering what was your reason for using yellow. I would have thought the ideal approach would have been seven different shades of black inks, say as in some of the Piezgraphy sets.

Sandy

Anyway, to try to be more clear... My R1800 has 8 ink channels. I bought empty after-market cartridges and filled one with yellow ink, three with light black, two with light-light black and two with a 50/50 mixture of yellow and light black, what I called "Y/LK". So it's a bit like one of those graduated inksets for regular B&W printing, in this case with 4 different inks spread over 8 channels. The mixing of the yellow/light black is a complication; I'm hoping that photo black will make a good substitute next time I try this.
!

Ben

 

[Ben Altman]

Hi Sandy,

Yellow blocks UV well, as you know. But it may have been a mistake to use it. I think I may have read some comments about the full black inks causing trouble, but at this point I'm not sure. As I said, next time I get to this I'll experiment with matte black and photo black. The results using yellow were fine, but mixing inks in a cartridge is problematical, as the mixture varies slightly each time the cartridge is filled, requiring adjustments to the profile.

I tried a peizography inkset briefly, but it is very fragile on OHP. So I thought I'd stay with Epson inks, as I know they stick to OHP and may be better for the printer. Wiz has some posts on this forum where he describes using home-made dilutions of carbon-black ink, and that may be a good method, though also subject to the mixing-variation problem.

Using the same ink in multiple channels means that for any given tone you have a lot of nozzles firing the same stuff at once. My theory, unsupported by any hard evidence, is that that helps to give smooth tones. Also, it's easier to write a profile for four ink densities than eight!

Best, Ben

Ben,

Just wondering what was your reason for using yellow. I would have thought the ideal approach would have been seven different shades of black inks, say as in some of the Piezgraphy sets.

Sandy

 

[Ron-san]

Hi Ron,

If I confused you I'm sure no-one else has a clue what I'm on about... if anyone else is even trying at this point.

Actually, I don't want to have a deep understanding of all those black boxes - that's why I don't use them. When I had one of those fancy Nikons I used to shoot everything on manual with the spot-meter... But also, it seemed like a good thing to be able to see exactly what's going on. Not sure I realized how much work I was letting myself in for. But my spreadsheet takes a lot of the "by hand" out of it.

Anyway, to try to be more clear... My R1800 has 8 ink channels. I bought empty after-market cartridges and filled one with yellow ink, three with light black, two with light-light black and two with a 50/50 mixture of yellow and light black, what I called "Y/LK". So it's a bit like one of those graduated inksets for regular B&W printing, in this case with 4 different inks spread over 8 channels. The mixing of the yellow/light black is a complication; I'm hoping that photo black will make a good substitute next time I try this.

If you look at the numbers in the profile in my last message you'll see that the curves for all cartridges with the same ink are identical. That's why only one of each shows on the plot I sent you by e-mail. I could use the "copy curve" function to build the profile in QTR, I guess, but the spreadsheet just duplicates the numbers for me, so I don't need to.

Hope that helps!

Ben

Ben-- Thanks, that clears things up a lot. I have considered the custom ink approach, but for one major practical reason have never done anything in that direction. I want to be able to use my printer for printing my wife's full color bird photos and other chores, as well as for making negs. So, for the time, I am committed to trying to make the best negs I can with the standard Epson K2 or K3 inksets.

I am still trying to understand exactly how your ink curves work and how you go about linearizing them. But that will come in time, I assume.

Cheers, Ron Reeder

 

[PVia]

I just have to chime in here on this old thread...

I've just experimented with Ron's QTR profile for silver printing on Ilford MG...and it is totally amazing. I used 50-70 cc of yellow filtration. 70 cc equals a Kodak filter for grade 1/2 (one-half) and worked out my exposure, which is roughly 3 stops more than my usual exposure for contact prints on this paper. Also, used Ansco 130 for 3 minutes.

I liked the test results on a small 4x4 image, and decided to print a 7.5x7.5 neg to see it bigger and it is awesome even when viewing with a 4x loup. Very smooth tones, gradations, etc...I'll try to post a scan later.

Thanks, Ron!

 

[sanking]

I don't do much silver printing but I agree. Ron's QTR profile for silve printing on Ilford VC paper gives great results. Ron is a great resource and we should all be thankful for his generosity in sharing his profiles.

Sandy King

I just have to chime in here on this old thread...

I've just experimented with Ron's QTR profile for silver printing on Ilford MG...and it is totally amazing. I used 50-70 cc of yellow filtration. 70 cc equals a Kodak filter for grade 1/2 (one-half) and worked out my exposure, which is roughly 3 stops more than my usual exposure for contact prints on this paper. Also, used Ansco 130 for 3 minutes.

I liked the test results on a small 4x4 image, and decided to print a 7.5x7.5 neg to see it bigger and it is awesome even when viewing with a 4x loup. Very smooth tones, gradations, etc...I'll try to post a scan later.

Thanks, Ron!

 

[Curt]

I also printed the negative with a 13 watt spiral BLB tube, placed at 36" from the printing frame, which is a very inexpensive and efficient light source for AZO.

That's extremely interesting, I use the same bulb that Michael Smith recommended. It's bright and hot. A BLB tube is something I must try. Would the bulb be similar to the one offered on the B&S site? I have a good supply of original AZO.

Thank you,
Curt