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Author Topic: ABW or Photoshop  (Read 32067 times)

texshooter

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Re: ABW or Photoshop
« Reply #40 on: May 29, 2013, 03:05:28 pm »


it would be great to see a new user's guide written.  I realize this is time consuming and I would gladly being willing to pay for it.  The problem is understanding the process of creating the curves for QTR, if you want to print from QTR. 

I second this.  Can someone explain in further detail the difference between QTR-Print-Tool and Quadtone RIP. I'm interested in buying if I can just wrap my head around it.
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royvharrington

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Re: ABW or Photoshop
« Reply #41 on: May 29, 2013, 03:22:04 pm »

Lively discussion, so I guess I should insert myself.

Jeff,
QTR is easiest to setup for USB with the automatic setup scripts. But you can manually set it up for various other connections.  Bonjour is the preferred method -- it supports: ethernet, WIFI, and usb port on the Airport. (some of the older printers had firewire but that connection was not possible). Look at the Tutorial.pdf last couple pages for the details.  The idea is to attach/create the printer in Print&Scan (Print&Fax in older OS's) and just use the script to add the curves.
If you'd like to see the ink usages of the various curves go to:
/Library/Printers/QTR/quadtone/<printername>/<curves>.quad
Double-click the .quad files or open them in QTR-CurveView for a graph of all the inks.

This is my take on the 3 basic ways to print B&W images on Epsons that I am familiar with:
1) Epson color driver
Pros:  uses standard and familiar workflow including ICC profiles -- provided ones and custom ones. you can edit your file for split-tones etc, but its an extra editing step
Cons:  uses more color inks which can give colorcast and metamerism issues
2) Epson ABW driver
Pros: uses less color inks, has some hue control of the image.
Cons: no split-tone, not planned for Color Management, B&W CM is not a huge issue because you can just edit your file with one AdjCurve to compensate. There are some builtin papers but you can't do any customizing for 3rd party papers.
3) QTR driver
Pros: uses least amount of color, split-tone builtin with lots of blending possibilities
its a pretty open system so a fair amount of 3rd party support for all kinds of setups.
Cons: if you want to grow your own there's a learning curve for doing that.

Industry standard ICC profiling has pretty much stuck with just color workflows -- RGB mainly plus CMYK for more advanced situations.  (grayscale has always been in the ICC standard but rarely used).  So for the 3 methods above only 1) has really embraced CM everywhere.  Most anything your download from Adobe, Epson, paper manufacturers will be regular color ICCs.

I imagine confusion over using these color ICCs with either 2) or 3) has been a headache for a long time.  This is probably why the triumvirate of Apple, Adobe and Epson have tried so hard to keep us from hurting ourselves.  But that's made it hard for those of us who want to do our own thing -- hence Print-Tool.

They've actually done a pretty good job at convincing many of us.  I've seen quite a few references to the notion that ABW is a "black box" so shouldn't be CM'd in the discussion.  But all drivers and devices are essentially black boxes.  We profile them so that a CM system can match screen views with printed output.  The idea is to match LAB values because that's what we humans perceive.  Color systems try to match L, A, & B, but grayscale tries to just match L.

The QTR program Create-ICC is just a simple way to create these grayscale ICCs for use with either ABW or QTR drivers. Note that there is an RGB version of this program but its still really just a grayscale ICC in an RGB format for programs/workflows that don't handle grayscale files or profiles -- which unfortunately seems to be becoming the norm.

None of this is really new -- been doing it since before ABW, but wrenches keep being thrown into the gears so its a never ending battle with the big guys.  

Roy

(my point of view is mostly from the Mac side, PCs will be similar.  But the big difference is QTR is not a driver there -- instead a separate program QTRgui which does no CM by itself)
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Alan Goldhammer

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Re: ABW or Photoshop
« Reply #42 on: May 29, 2013, 04:07:24 pm »

Alan, reverting to Reply 17, I see that QTR IS available in a Mac version. I doubt I'll have time to work with it over the near future, but I shall be complementing the material in reply 12 with additional measurements of L*a*b* deltas compared between ABW-Normal and Photoshop Manages Color, using one of Bill Atkinson's grayscale test ramps. I'll be reporting those results in this thread I hope some time today. This work of course is limited to my Epson 4900 and driver version 8.64 on Mac OSX.

Regarding the ABW tone settings, "just gamma adjustments to the print" are of course kind of important when you can actually see differences that impact on the character of the outcomes.

BTW - very dangerous indeed to take a day off from "LuLa".  :-)
Yes, it is available for MacOS but you have to use the driver to print.  WinOS allows you to print with the Epson ABW driver but with a dedicated ABW profile.  You are correct about the tone settings and importance.  It would have been nice if Epson would have programmed in a print preview feature so that you could see what the result might look like.

Alan

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royvharrington

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Re: ABW or Photoshop
« Reply #43 on: May 29, 2013, 04:38:28 pm »

I second this.  Can someone explain in further detail the difference between QTR-Print-Tool and Quadtone RIP. I'm interested in buying if I can just wrap my head around it.

I admit more and newer docs would be good.  Unfortunately there are so many possible levels to write it at.
There are some many combinations of OS version, printers, inks, profiling devices -- many of which I don't have.
Tom's doc is old and PC oriented but the concepts are all still the same.  Amadou's workflow doc is Mac oriented but emphasizes that you don't need to "do it all".  Hardly anyone needs to start from scratch.  There's a lot of desire in the beginning to "do the best I can by customizing it all".  Do the simplest workflow for a long time.

Print-Tool and QTR are two completely different products. 
QTR is the long time printer driver for Epsons.  It has all kinds of ways to control each of the individual inks for printing B&W images.  It supports dozens of Epson printers and comes with curves (QTR profiles) for many combinations of printer and ink.  It's pretty turnkey for most peoples needs.
Print-Tool (I probably should drop the QTR in front of the name) is a high level interactive program.  Its for taking a piece of paper and laying out images, rotating, resizing and positioning.  If you've used Lightroom Print module its similar.  It's real easy to use and intuitive (at least I think so).  It works with lots of file types and prints to any standard OSX print driver -- color or B&W.  The main impetus was to do color management in a straightforward, correct and flexible way -- but altogether its a simple, easy print layout program.  Its the only program I use for printing images -- with QTR for B&W, with Epson for color.

Roy
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Joe S

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Re: ABW or Photoshop
« Reply #44 on: May 29, 2013, 09:39:35 pm »

Roy,

So, given the QTR default curves, do you have any ink usage data regarding which inks are used for the various curves?



Right clicking on any of the curves in the QTR curve setup box will give a graph of the curve.
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MHMG

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Re: ABW or Photoshop
« Reply #45 on: May 30, 2013, 08:38:25 am »


Print-Tool (I probably should drop the QTR in front of the name) is a high level interactive program.  Its for taking a piece of paper and laying out images, rotating, resizing and positioning.  If you've used Lightroom Print module its similar.  It's real easy to use and intuitive (at least I think so).  It works with lots of file types and prints to any standard OSX print driver -- color or B&W.  The main impetus was to do color management in a straightforward, correct and flexible way -- but altogether its a simple, easy print layout program.  Its the only program I use for printing images -- with QTR for B&W, with Epson for color.

Roy


A sorely needed contribution to the Mac platform! I will check it out  Does it have any text handling ability such as control on adding titles, description, metadata to the page layout?  I realize you are on an early version and that text can be added directly to image files by other software, so maybe that's asking too much, but my "go to" page layout-for-print software at this time is InDesign. Amazing control on both images and text plus full color management and even ability to print unflattened PSD files correctly. Sadly, InDesign's prohibitive cost, only to be made worse with Adobe's push to the cloud, rules an Indesign print workflow out for many of my colleagues, friends, and students.

cheers,
Mark
http://www.aardenburg-imaging.com
« Last Edit: May 30, 2013, 08:39:58 am by MHMG »
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royvharrington

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Re: ABW or Photoshop
« Reply #46 on: May 30, 2013, 01:11:08 pm »

A sorely needed contribution to the Mac platform! I will check it out  Does it have any text handling ability such as control on adding titles, description, metadata to the page layout?  I realize you are on an early version and that text can be added directly to image files by other software, so maybe that's asking too much, but my "go to" page layout-for-print software at this time is InDesign. Amazing control on both images and text plus full color management and even ability to print unflattened PSD files correctly. Sadly, InDesign's prohibitive cost, only to be made worse with Adobe's push to the cloud, rules an Indesign print workflow out for many of my colleagues, friends, and students.

cheers,
Mark
http://www.aardenburg-imaging.com

Mark,

Text is not supported now.  But it is something I've thought of and its on the list of
potential features.

PSD files are supported but you need to save in compatibility mode which adds a flattened layer
as well as the traditional layers.  I doubt that anyone but Adobe can support processing
Photoshop layers.  (Aside: I think with the new Adobe CC licensing the compatible mode ought
to always be used so you can get a copy of your image if you ever stop paying).

Roy
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MHMG

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Re: ABW or Photoshop
« Reply #47 on: May 31, 2013, 04:37:10 pm »

Mark,

Text is not supported now.  But it is something I've thought of and its on the list of
potential features.

Roy


Not to worry. I just purchased Print Tool and quickly concluded it deserves a big round of THANKS for all us Mac users. I have been looking for an elegant solution for friends new to the MAC and for new photography and printmaking students as well to lift the absurd complexity of the Mac printing pipeline off their backs at least until they get more experience. Print Tool is it. Apple PAGES would have been good, but the printer pipeline is just as cumbersome and loaded with non sticky settings, bugs, and subsequent uncertainty as any other software currently running on the Mac save for a few Adobe applications (but those solutions are beyond financial reach for many). Your Print tool software handily eliminates that uncertainty.  An added bonus:  It provides a clean path to print non color managed ICC profiling targets but without the scaling quirkiness of Adobe Color Print utility.

My first wishlist request wouldn't be text. If would be an "Edit with" command that when you click on an image on the page layout and invoke the "edit with" command it would allow a simple round trip to and from one's desired image editing software. Rulers and full page layout with printer margins showing as dashed lines on the page would be good, too. I've got other ideas as well I will send to you offline, but even now, Print Tool is a very elegant answer to a printing bottleneck that has for many years exhibited seriously unMac-like behavior on a Mac for those of us who like to make prints from our photos.


cheers,
Mark
http://www.aardenburg-imaging.com
« Last Edit: May 31, 2013, 04:53:16 pm by MHMG »
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Mark D Segal

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Re: ABW or Photoshop
« Reply #48 on: May 31, 2013, 04:43:54 pm »

Not to worry. I just tried Print Tool and quickly concluded it deserves a big round of THANKS for all us Mac users.

cheers,
Mark
http://www.aardenburg-imaging.com

Mark - no disrespect to Roy's efforts, but I'm curious - what does it do that Mac users can't do in the Lightroom Print module? I too would like a print function that accommodates text. It could come in very handy.
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Mark D Segal (formerly MarkDS)
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digitaldog

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Re: ABW or Photoshop
« Reply #49 on: May 31, 2013, 04:49:35 pm »

Mark - no disrespect to Roy's efforts, but I'm curious - what does it do that Mac users can't do in the Lightroom Print module? I too would like a print function that accommodates text. It could come in very handy.

You can print without color management for one. That's useful for us Mac people.

The UI and overall functionality is ACPU on steroids, it doesn't appear to have scaling issues like the Adobe product. I purchased it, looks very nice although I think the price is just a tad high.
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Mark D Segal

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Re: ABW or Photoshop
« Reply #50 on: May 31, 2013, 05:00:18 pm »

Interesting comparison with ACPU Andrew, but my question is about comparison with LR's Print module. If it can do much more much better ............
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Mark D Segal (formerly MarkDS)
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digitaldog

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Re: ABW or Photoshop
« Reply #51 on: May 31, 2013, 05:48:55 pm »

Interesting comparison with ACPU Andrew, but my question is about comparison with LR's Print module. If it can do much more much better ............

You can't print without color management in LR.
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MHMG

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Re: ABW or Photoshop
« Reply #52 on: May 31, 2013, 05:55:50 pm »

Mark - no disrespect to Roy's efforts, but I'm curious - what does it do that Mac users can't do in the Lightroom Print module? I too would like a print function that accommodates text. It could come in very handy.

The Print module in LR has a fairly steep learning curve, IMHO, steep enough for me at least not to be willing to devote the time necessary to master it. Because I've mastered InDesign and InDesign can handle multi page text and graphics with ease plus give me a competent color managed workflow on a MAC (no small feat), I just didn't want to invest the learning time into LR's print module, although I use LR for cataloging and preparing RAW files for further editing in PS. If it works for you, then you've invested that quality time, and you can probably justify that effort as a reason to stay away from InDesign :D. For me, LR just isn't robust enough compared to InDesign, but as I noted in an earlier post, InDesign's steep financial cost and steep learning curve also makes it an impractical recommendation for many folks who simply want to print their photos cost effectively yet with decent color managed output.

Moreover, if a friend stops by and would like to make some prints, or I hold a weekend printmaking session for new students in my studio, I want MY friends and students, not me, to be able to print their photographs on any of the printers in my studio without having to get steeped in the whole LR workflow (unless LR is the reason for the class), or custom plugins/RIPs for specific printers, or InDesign for that matter. Mac users needed a clean and simple printer user interface that gets a color managed workflow right without having to jump over tons of unique app/printer driver hurdles. I.E.,  Learn one printmaking interface without a lot of blood, sweat, and tears. Print to any printer.  Roy's Print tool is as good as it gets for this purpose on the Mac Platform. I'm not one to endorse products lightly, but frankly, I'd love to see Apple license Roy's Print Tool software to include this app free in the MAC OS and pay him to develop it a bit further always with a mind to keeping that sheer simplicity! Very Mac-like!

cheers,
Mark
http://www.aardenburg-imaging.com
« Last Edit: May 31, 2013, 05:58:51 pm by MHMG »
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MHMG

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Re: ABW or Photoshop
« Reply #53 on: May 31, 2013, 08:48:33 pm »

And one other thing. For less than $40, Roy just gave me a great fully color managed print pathway for my Mac independent of relying on any Adobe software of any sort. Maybe not Relcol w/bpc rendering intent, but I know a simple workaround for that.  Adobe management... Are you listening?   More interesting non Adobe software likely to appear in the months/years before perpetually licensed CS6 becomes a dinosaur.

regards,
Mark
http://www.aardenburg-imaging.com
 
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cybis

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Re: ABW or Photoshop
« Reply #54 on: June 01, 2013, 03:42:09 pm »

Seems odd to me, the minimum droplet size hasn't changed on the Epson wide format models since the 9800; 3.5 picoliter where the 9600 had 4 picoliter. The next droplet size on the 990 will be something like 10 picoliter, a size that should be quite visible. It is more likely that the 9900 dithering/weaving did improve beyond the Gutenprint driver.

Ok, this is embarrassing. I need to apologize to everyone (and to Roy in particular). I was wrong regarding the droplet size used by QTR. There is no difference in droplet size between QTR and Epson. I had confused the tests I ran a few months back with Gutenprint and QTR.  :-[

As you said, Ernst, the difference is entirely in the dithering algorithm.
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Mark D Segal

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Re: ABW or Photoshop
« Reply #55 on: June 01, 2013, 03:53:20 pm »

.............. I doubt I'll have time to work with it over the near future, but I shall be complementing the material in reply 12 with additional measurements of L*a*b* deltas compared between ABW-Normal and Photoshop Manages Color, using one of Bill Atkinson's grayscale test ramps. ...................This work of course is limited to my Epson 4900 and driver version 8.64 on Mac OSX.


I've now had a chance to complete a series of measurements and I am providing them in the attachments. The observations from this information are as follows: (Please note these results are valid only for Ilford Gold Mono Silk paper printed in my Epson 4900 using the Epson Ultrachrome HDR inkset.)

L*:

"Read vs ref" means the values read off the print versus the value of L* on the target as measured in Photoshop. No method can print L*=0 blackness, but at the L*=0 file value, ABW produces about 2 levels lower lightness than the ICC profile. However, at that level of blackness, the difference is not visible on this (or perhaps any other) paper. By L*=3, ABW-Dark remains closest to reference values up to about L*=40. Thereafter, ABW-Dark and the ICC profile perform about as well (but in opposite directions) up to about L*=68. Thereafter, the ICC profile performs closest to reference values till L* gets into the mid-90s, at which point all of them are at their most deviant. From L*=3, ABW-Normal produces lighter results throughout than the other two, either because its positive variance is larger, os its negative variance is smaller, until approaching L*=100.

a*:

For both the a* and b* readings, the values shown are departures from 0 (neutral).

These measurements test for adherence to neutrality along the a* and b* axes (the closer to zero the readings, the better the neutrality). The most important observation about this data is that the variances don’t exceed 1/128th of the scale. That’s why it’s hard to perceive any green or magenta bias in any of these results. The largest deviations occur at the bright end of the scale where they would be less visible. The ICC profile on the whole shows less deviation from zero between L* levels 9 and 50. From L* 56 upward, ABW returns results marginally more neutral than the ICC profile.

b*:

This is the blue-yellow axis, and deviations from neutral here would influence the extent to which one perceives the print to be relatively warm or cool. To preface the observations, Ilford has informed the public in one of a previous Lula thread that IGMS does contain OBA. This would influence a spectrophotometer to return results with a bluish bias, however, the Pulse spectro I am using is UV corrected, which should mitigate this bias to an extent I have not tried to isolate. It think it likely that the OBA presence in this paper contributes to the somewhat negative bias in the b* readings. From L*9 onward, the ICC profile produces more neutral outcomes than the ABW settings, except in the range of L*68 to L*75, where they are clustered very closely, and again at L*94 to L*97. Having said all this, it is important to retain the fact that these long bars are measuring small differences, insofar as the maximum variance of about -1.50 is only slightly more than one percentage point of the scale on one side of zero.

The main conclusion I come to is that all this measuring is inconclusive. One needs to make prints and use what one thinks looks best. For example, in the Northlight B&W test page, I found a slight margin of preference for ABW Normal given how well it opens shadow detail, but the ICC profile is not far behind. Based on these tests, previous tests, and previous test prints using both an ICC and ABW-based workflow (but no QTR), I would normally opt for the ICC-based workflow because I really do like the ability to soft-proof my actual photos before sending them to print.
« Last Edit: June 01, 2013, 04:02:41 pm by Mark D Segal »
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Mark D Segal (formerly MarkDS)
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Mark D Segal

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Re: ABW or Photoshop
« Reply #56 on: June 01, 2013, 03:59:41 pm »

In the previous post I reached my maximum of allowed attachments. There is one more, showing the grayscale target (from Bill Atkinson) from which I read the results. With this target the far left bar requires 3 readings top, center and bottom. The following bars require two readings - center and bottom, as the top of the bar measures the same as the bottom of the previous one. One can of course make more measurements of different values from this target as there are more discrete luminance values per bar, but I considered a total of 33 readings across the scale sufficient to see the main tendencies of interest.
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NeroMetalliko

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Re: ABW or Photoshop
« Reply #57 on: June 01, 2013, 09:07:18 pm »

The main conclusion I come to is that all this measuring is inconclusive. One needs to make prints and use what one thinks looks best. For example, in the Northlight B&W test page, I found a slight margin of preference for ABW Normal given how well it opens shadow detail, but the ICC profile is not far behind. Based on these tests, previous tests, and previous test prints using both an ICC and ABW-based workflow (but no QTR), I would normally opt for the ICC-based workflow because I really do like the ability to soft-proof my actual photos before sending them to print.

Hello Mark,
many thanks for submitting your test data. it is really appreciated.

I have some small questions:
- the ICC used was the Ilford provided one or a custom one?
- It was used in relative colorimetric + black point compensation or in different way?
- regarding the a* and b* values of the white patch (paper white) I see a strange inconsistence for the ABW-normal case. Usually I never see this kind of difference in different instances of a paper white measurement. Are you sure do you have not accidentally swapped the a* with the b* values for this single wedge one (L* 100 of the ABW-normal set)? Because the other two are good matching and if you swap the a* and b* values of the not matching one (ABW-normal) it seems again a good match with the other two.

However I think that your measurements are not inconclusive at all.
I have taken your data and I made the same Lab graph I usually do for my linearization test for all the 3 cases you showed (ICC, ABW-normal and ABW-dark), you can find it in the first attachment.

The main difference is that I have highlighted the linear straight line (visible as dotted line) between measured black and measured white, because this line is my usual adopted reference target for my L* linearization.
- As visible, in the first (left) graph the ICC L* shape is a typical "S" shape, with slightly compressed shadows/highlights and slightly expanded midtones
- in the center graph the ABW-normal L* shape is always a little bit too high
- the right graph clearly show a quite good match of the ABW-dark L* shape with the theoretical linear target, this is clearly the best of the three if a true linear approach is desired.

Please, note this is not the first case I find this kind of coincidence.
In my second attachment you can find a similar comparison I have done using Ilford Gold Fibre Silk.
I used my Epson R3000 and Epson K3 VM inks. ICC was the Ilford provided one used in relative colorimetric and black point compensation on.
The strip was made of only 18 B&W wedges (not 33 like yours), the measurements were done with my humble ColorMunki.
- As you can see the ICC L* graph is not so good as yours, remaining always under the L* target line
- ABW-normal is very similar to yours, remaining always over the target line
- ABW-dark is the best of the 3, with good match to the L* target line and very similar to yours too

In ABW the gray tone is more neutral than the ICC one, and not so slightly bluish as the one you found (ColorMunki is UV-cut).
Overall in ABW the gray tone is very neutral, becoming a little bit warm only in proximity of the paper white, which is a bit warm for this paper.
In addition note that the L*, a* and b* values of the paper white is near perfectly matching in all the 3 cases.

In my humble opinion these data are very interesting because they show that the ABW modes provide results that are similar for a 4900 + Gold Mono silk and R3000 + Gold Fibre silk. (There is a little difference in the overall b* shape, but in different paper/coating/inks it could be expected).

Your ICC is clearly better performing that the one used in my case, ABW-dark is the best choice for L* linearity in my opinion and gives deeper blacks than ICC, but I agree with you that if you want to do some tone grading and you will be able to see on screen the results before printing, the ICC workflow is your solution.

I hope it will be useful.
Any comment is welcome.

Ciao :)
Andrea
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Mark D Segal

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Re: ABW or Photoshop
« Reply #58 on: June 01, 2013, 09:49:00 pm »

Hello Andrea,

I like the way you prepared your graphs. They add another perspective.

I doubt that I swapped the a* and b* values for 0 in ABW Normal, but I would need to remeasure that patch to be certain. I'll look into it tomorrow and if there is a correction to be made I'll post it here. It could also be a glitch with the reading from the instrument itself. By the way, my Pulse spectro does have a UV filter.

The ICC profile used for these tests is the Ilford-supplied profile, RelCol with BPC and the paper selection in the driver is keyed to their recommended Epson paper.

You are correct that ABW Dark is somewhat more linear, but the differences compared with the ICC profile are not huge, so in the final analysis it boils down to which approach makes more satisfactory-looking photographs, and that would vary from one image to the next. That is why I think the exercise is fundamentally inconclusive even though one sees the technical differences. Linearity isn't a holy grail, it is a technical property which comparatively speaking either suits the image better or it doesn't. While the ABW delivers lower black values at L* = 0 than does the ICC profile, I, at least, can't see the difference on paper at that level of blackness and difference between the two. While it's good to know these differences quantitatively, in the final analysis, what I see is more significant than the data, because the ultimate objective is to enjoy the photographs one makes.

I think the main thing that distinguishes your b* results from mine is that IGFS has either no or very little OBA compared with IGMS, and that affects both appearance and readings regardless of the filter on both of our instruments.

I agree with you - there are some striking similarities between the two sets of results, especially after taking into account the basic differences between the two papers.

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NeroMetalliko

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Re: ABW or Photoshop
« Reply #59 on: June 02, 2013, 04:27:39 am »

You are correct that ABW Dark is somewhat more linear, but the differences compared with the ICC profile are not huge, so in the final analysis it boils down to which approach makes more satisfactory-looking photographs, and that would vary from one image to the next. That is why I think the exercise is fundamentally inconclusive even though one sees the technical differences. Linearity isn't a holy grail, it is a technical property which comparatively speaking either suits the image better or it doesn't. While the ABW delivers lower black values at L* = 0 than does the ICC profile, I, at least, can't see the difference on paper at that level of blackness and difference between the two. While it's good to know these differences quantitatively, in the final analysis, what I see is more significant than the data, because the ultimate objective is to enjoy the photographs one makes.

Hello Mark,
many thanks for sharing your valuable experienced opinion,
I think that it is a very precious opportunity we have here and I really appreciate it a lot.

I'm glad you found interesting the way I analyzed/showed the data in the graph, by taking as reference the real potential straight line between printed black and paper white. I have adopted this approach as my standard evaluation tool and I always found it really useful for comparisons and for complementing my real world evaluations.

I have to admit that the Ilford ICC you used, even if not perfect, is a very good one, considering that it's not custom made. I dare to say is unusually good for a canned profile. :)
The Ilford ICC I have used in my test, with the same settings, is obviolusly less performing and too dark.
In my experience I have often observed this kind of deviations and even more.
For this reason usually I need/prefer to build a linearization curve: it provide me a reliable/consistent/comparable reasonably good starting point for all the work.

I fully agree with your points, the linear line target is not a holy grail, and the personal supervision is always the most decisive thing.

The reason why I said these kind of analysis are not inconclusive (probably misunderstanding the real "inconclusive" word significance, sorry for that) is because I think that these are really significant, providing some objective/repeatable information regarding how a real print could probably look on paper.
I know that one can figure it out by a visual inspection, but with a simple 18 strip and a graph you know immediately if the system is spot-on or not, how much, and where are the zones that are needing more attention, if any.
Based on my little experience by doing it consistently, it will greatly improve the personal knowledge allowing for less trial/error steps in the long run.
In addition, I full agree that each image needs a different "finished" look, and for this exact reason I prefer that the overall control regarding the related corrective actions, when needed, could be possibly performed by myself in the most transparent way, and not hidden in the ICC/print process in a not so consistent and/or easily predictable way.

In any case, as you perfectly said, the most important thing is to enjoy the photographs one makes.

Thanks again.
Ciao :)

Andrea
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