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Author Topic: Big difference between (good) proofing paper and final print paper!  (Read 13651 times)

Garnick

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #20 on: October 12, 2017, 09:36:02 am »

Gary, the key point is that the paper was designed for proofing press output. Phil made that clear. If anyone wants to use it for proofing inkjet prints to be made on another type of media they do so at their own risk, because RELIABLE proofing for a press or for a professional inkjet printer requires that the proofing papers are bespoke to the intended output device/paper.

Hi Mark,

Yes, I am well aware of the initial post and the fact that the paper used is for PrePress proofing, as stated by Phil.  However, as the thread developed the term "Proofing" became associated with InkJet printing as well, to which I asked the following question. Whats' the difference between "proofing" for in-house inkjet printing and "testing" for in-house inkjet printing?"  Are they not the same thing, and if not, how so?  There would seem to be no difference at all, and yet on many occasions the term "testing" has been associated with the possibility that ones display is not calibrated and profiled, and ones colour management is completely out of wack.  That was the key point to my reply.  This is a quote of a reply from Wayne Fox - "I proof on either Epson Premium Semigloss or Epson Premium Luster, final prints are Epson Legacy baryta.  both are custom profiled. Match is quite close, visually close enough to be a valid proof and trust printing on the baryta".  So once again I ask, as related to inkjet printing, what's the difference between a test print(strip) and a Proof Print?  Perhaps the size?

Gary   
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Gary N.
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Garnick

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #21 on: October 12, 2017, 09:56:20 am »

I proof on either Epson Premium Semigloss or Epson Premium Luster, final prints are Epson Legacy baryta.  both are custom profiled. Match is quite close, visually close enough to be a valid proof and trust printing on the baryta.

Hi Wayne,

I had every intention of responding to your reply here, but time got in the way I'm afraid.  However, since I have just quoted your reply to perhaps make a point, I felt it only proper that I at least reply directly to what you have mentioned here.  The procedure you have outlined here is very familiar, and one I have been using for many years, dating back to traditional Colour and B&W printing.  Of course the equipment, papers and procedures then were totally different from today's, but the basic premise is the same.  I do however have one question.  You use the term "proof" in your reply, but would you agree that the term "Test" would also apply to you procedure.  After all, is that not what a "Proof" print is.  Is it not a "Test" of the whole image to determine if what you are viewing on your display is being properly transferred to paper?  It would seem that a lot of folks cringe at the mention of a Test, or Test print, but have no issue with the term "Proof Print", as it applies to inkjet printing.  Personally, I believe they are one and the same, but I stand corrected if I am mistaken.

Gary 
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Gary N.
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Mark D Segal

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #22 on: October 12, 2017, 10:09:07 am »

Hi Mark,

Yes, I am well aware of the initial post and the fact that the paper used is for PrePress proofing, as stated by Phil.  However, as the thread developed the term "Proofing" became associated with InkJet printing as well, to which I asked the following question. Whats' the difference between "proofing" for in-house inkjet printing and "testing" for in-house inkjet printing?"  Are they not the same thing, and if not, how so?  There would seem to be no difference at all, and yet on many occasions the term "testing" has been associated with the possibility that ones display is not calibrated and profiled, and ones colour management is completely out of wack.  That was the key point to my reply.  This is a quote of a reply from Wayne Fox - "I proof on either Epson Premium Semigloss or Epson Premium Luster, final prints are Epson Legacy baryta.  both are custom profiled. Match is quite close, visually close enough to be a valid proof and trust printing on the baryta".  So once again I ask, as related to inkjet printing, what's the difference between a test print(strip) and a Proof Print?  Perhaps the size?

Gary   

Proofing and test strips have the same basic objective. When I think of proofing, however, I think of technology that is burrowing down on the print's overall accuracy of tonal and chroma rendition, while test strips are spot samples looking for certain visually acceptable outcomes without wasting a whole sheet of paper. I think Wayne's reply to you quoted above makes sense for those situations in which proofing or testing provides substantial value-added. The hope - and the experience of many - is that with today's colour management technology the need for proofing/testing has been ratcheted downward substantially, but not eliminated in all circumstances. 
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Mark D Segal (formerly MarkDS)
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narikin

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #23 on: October 12, 2017, 11:20:43 am »

The Platines in general are a moving target, from the first version to the last I see an increase in white reflectance going from Lab L 97.0 to L 99.1. There is more gain in dynamic range with Lab L steps in white reflectance than in Dmax but Mark already mentioned a better black Lab L 4.0 versus the L 3.0 for the EPWSM. Based on the profiles data. Whether the Platine profile still represents the last batches of Epson Platine is one uncertainty.


Agree - very interesting that the Platine's have been improving over the years since Canson's first introduction. They indeed have a much better white point to them now, which is remarkable for an all-cotton OBA free paper...  Incidentally this print I was impressed by was on Canson's own version, bought very recently.  (there is no 60" Epson Legacy Platine available, yet. I'd love it if there were!)

I think people have got confused by the 'proofing' nomenclature. I'm with Ernst on this, the fact that its designed to be a reliable OBA free substrate with a good neutral white point, and was Epsons own choice to promote their inkjet printers (not not press proofing) means it is excellent for proofing most things, not just offset printing press. Its just that things get even better with a 'top drawer' Baryta or Platine. As they should, given the price!

(and nb it was not a color shift between the two prints, they were both bang-on,  but in the pricey paper there was more color-depth overall. As Mark says you would not have appreciated it till they were side by side, then it was immediately obvious)



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Ernst Dinkla

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #24 on: October 12, 2017, 11:38:38 am »

This is interesting, and somewhat confusing as well.  Now the fact that I am easily confused is probably obvious, but I digress.  The confusing part of this thread, for me at least, is the seemingly overlapping use of the term "proof", and or "proofing paper".  This thread started with a comparison of the differences between an Epson "Proofing Paper" and another Epson Paper on which the final print would be produced.  As the thread progressed it touched on the difference between "Pre-Press" proofing and proofing for InkJet Printing.  Since I have no need for Pre-Press proofing I will concentrate of the posts that referred to the procedure of what I will call "InkJet Print Proofing", since that would seem to be what it is.  Perhaps I'm reading these posts incorrectly, it is early morning and my java hasn't kicked in yet.  However, I do believe I have more or less nailed it, and it seems to me that the word "Proofing" here in some instances does directly apply to InkJet Printing.  In other words, one would create a "proof" print on a particular paper, view that print(proof) under proper lighting conditions, and then decide whether or not it is ready to go to a final print on another paper, or perhaps the same paper.  Now, if I have indeed not grasped the basic premise of the original post, as well as various others, please set me straight.  However, if I have "nailed it", on any level, that "proof print" could easily fall under the umbrella of what has been called "hard proofing", or that much maligned word, "testing".  Otherwise, what is the reason for a "Proof Print" when referring to "in house" inkjet printing?  I mention this only because I have, on several occasions, made reference to my workflow, which includes a small test of a particular area of an image, to make sure that what I am seeing on my display will transfer properly to the final printed image.  And on many occasions I have been reminded that if my display is properly calibrated and profiled, along with a colour managed workflow, there should be no need for a test strip.  Therefore, the following question.  What is the difference between a test strip and a "proof print".  The only difference I can determine is size.  My test strip is of a small, but critical section of the image, whereas the "proof print" is the full image.  And I also, to some extent, test(proof) on a paper other than the one on which I will produce a final print.  Case in point - when printing on Breathing Color Canvas(Chromata White Matte) I test on Epson Enhanced Matte paper.  The latest iteration of that paper is a dead match for the canvas, at least to my eye, and a much more economical method of testing.  However, if I'm not totally certain, I will run a section of the image on a 17" roll before committing to a final print.  The previous versions of EnhMatte were not as close as the latest one, so I had an adjustment action for them.  And by the way, that's the only use I have for EnhMatte. 

Once again, please let me know if and how I have misinterpreted the OP, and or other replies.  But not until your morning java has kicked in  ;) 

Gary       

               

When the end product is a print on an inkjet paper with a small gamut then another paper could be used for proofing if it has a similar paper white + texture and a wider gamut. You need a device-link profile that represents the first paper's gamut within the last paper's gamut. That is roughly describing how inkjet prepress proofing is done for the offset, gravure etc press papers that have a smaller gamut.

However in the OP's case the gamut of the paper the proof is made on is somewhat smaller and most likely it has another gamut shape, say the reds strong enough, the blues less. There is no device-link profiling used and that would not help much either as the EPWSM has a smaller gamut. If the most saturated blue is still weaker than that of the Platine no profile would compensate that. So gamut size in numbers is not telling all, a virtual 3D shape of both is often more revealing.

Normal paper profiles describe the gamut of a paper/ink combination. Depending on the CM rendering choices, the image with assigned color space is fitted within that specific paper/ink gamut.  That does not mean images will be alike when printed on different papers though rendering choices like relative and absolute colormetric should bring more uniformity in less saturated colors, the saturated ones might too or are clipped at the boundaries of the different gamuts, depending on the gamut sizes and shapes. If you want to use the full gamut of the paper that makes the end print and you start from an image with a big color space assigned then relative or absolute colormetric are not the best CM rendering choices. A Catch 22 situation for proofing photo's. Better take the same paper with a lower weight if available. Another factor is the profile creator and the choices made in profile creation. Different sources for the profiles used is not adding to a better match.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots



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Ernst Dinkla

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #25 on: October 12, 2017, 11:46:37 am »

Agree - very interesting that the Platine's have been improving over the years since Canson's first introduction. They indeed have a much better white point to them now, which is remarkable for an all-cotton OBA free paper...  Incidentally this print I was impressed by was on Canson's own version, bought very recently.  (there is no 60" Epson Legacy Platine available, yet. I'd love it if there were!)

I think people have got confused by the 'proofing' nomenclature. I'm with Ernst on this, the fact that its designed to be a reliable OBA free substrate with a good neutral white point, and was Epsons own choice to promote their inkjet printers (not not press proofing) means it is excellent for proofing most things, not just offset printing press. Its just that things get even better with a 'top drawer' Baryta or Platine. As they should, given the price!

(and nb it was not a color shift between the two prints, they were both bang-on,  but in the pricey paper there was more color-depth overall. As Mark says you would not have appreciated it till they were side by side, then it was immediately obvious)

The green plot with the dropping left side curve is the EPWSM one, could not fetch that within the screengrab.

The Platine plots show the increasing white reflectance between old and new batches of the Canon quality but also those of other brands. I am still convinced the source is the same.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots

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Garnick

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #26 on: October 12, 2017, 11:54:01 am »

Proofing and test strips have the same basic objective. When I think of proofing, however, I think of technology that is burrowing down on the print's overall accuracy of tonal and chroma rendition, while test strips are spot samples looking for certain visually acceptable outcomes without wasting a whole sheet of paper. I think Wayne's reply to you quoted above makes sense for those situations in which proofing or testing provides substantial value-added. The hope - and the experience of many - is that with today's colour management technology the need for proofing/testing has been ratcheted downward substantially, but not eliminated in all circumstances.

I agree Mark, and your breakdown of the difference between a test strip and a proof is "spot on".  Of course if I am printing reproductions of original artwork I would be perhaps running "tests strips" of various and troublesome areas of the image, since sometimes not all colours reproduce as expected, or as required.  In that case it's a matter of isolating that area and working on it individually.  And often the first "final" print actually becomes a Proof, especially if I have perhaps overlooked an area that becomes problematic, in which case the previous procedure comes into effect.  However, except when printing on canvas, I would never test(proof) on any paper other than the one on which the final print would be produced.  Simply too many possible variables to overcome, especially in critical situations.
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Gary N.
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digitaldog

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #27 on: October 12, 2017, 12:09:44 pm »

Yet Epson used the Proofing White paper in advertising to boast the wide gamut of the Epson x900 printers generation, not another RC or baryta photo quality paper. The ads were not aimed at prepress customers but at the photographer's market. And that gamut was wide at the time. An Epson representative could not point to another difference to the usual photo quality RC papers but the very low OBA content.
Proofing paper and proofing in total is an attempt to simulate one printing process with another. It doesn't work if one paper is different from the other. This has nothing to do with color gamut per se as the idea is both proof and final print have to have approx. the same color gamut or one goes out of their way to convert so the gamut 'issue' is moot. 
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Farmer

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #28 on: October 12, 2017, 02:39:13 pm »

Would it still look better to them if they didn't know?

It would seem from Mark's data that the measurements we have don't explain the "nothing like" difference perceived by the OP.

That leaves two possibilities: something is being missed by the measurements, or the difference is mostly imaginary. Which is why any serious tests of perception need to be done blind (so to speak).

In the examples I was citing, yes, to them.

All papers are different, which is why we use different ones for different needs, looks, etc.  As Andrew just pointed out, two different papers can be technical matched in terms of colour rendition, but they're still different.

Comparing substrates of different weight, thickness, whitepoint, coating, texture, OBA, etc. etc. are obviously going to give you different results even if they might technically have similar gamuts and different ones will suit different purposes for different people.

It's not always down to the numbers.
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Phil Brown

digitaldog

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #29 on: October 12, 2017, 02:49:17 pm »

It's not always down to the numbers.
The numbers are great when they tell us something about say color accuracy and then a dE Metric. They are pretty awful, based on current technology available, to tell us much about color appearance.
The reason why viewing a print is more valid than measuring it is because measurement is about comparing solid colors and their resulting set of numbers. Color appearance is about evaluating images and color in context which measurement devices can't provide. Colorimetry is about color perception. It is not about color appearance. Colorimetry based on solid  colors in very specific ambient and surround conditions.
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Farmer

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #30 on: October 12, 2017, 05:58:34 pm »

Nice, clear summary, Andrew - thanks!
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Phil Brown

Mark D Segal

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #31 on: October 12, 2017, 07:53:59 pm »

The numbers are great when they tell us something about say color accuracy and then a dE Metric. They are pretty awful, based on current technology available, to tell us much about color appearance.
The reason why viewing a print is more valid than measuring it is because measurement is about comparing solid colors and their resulting set of numbers. Color appearance is about evaluating images and color in context which measurement devices can't provide. Colorimetry is about color perception. It is not about color appearance. Colorimetry based on solid  colors in very specific ambient and surround conditions.

Yes, this is a keeper, well worth committing to memory.

I sometimes even wonder about the extent to which the results of colorimetry allow us to make reliable predictions of color perception. I think color scientists have been studying this question, with good reason, for a long time.
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Mark D Segal (formerly MarkDS)
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tastar

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #32 on: October 13, 2017, 01:03:12 pm »

Just for fun we profiled two papers, creating RGB profiles - Epson Standard Proofing Paper 240 and Epson Legacy Platine. We didn't have an open roll of Epson Proofing SemiMatte, but the description for this paper is very similar to the Standard Proofing Paper that we used. And, it doesn't have any OBA's like the newer proofing papers do.

The printed results on the two papers were almost identical visually, and the gamut maps of the two profiles were almost identical as well. We also tried the canned Epson profile for the Platine and it was close to our created profiles but not as exact a match as printing from the profiles that we created. Printing was done on an Epson SureColor P9000.

Tony
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Ernst Dinkla

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #33 on: October 14, 2017, 05:23:32 am »

Just for fun we profiled two papers, creating RGB profiles - Epson Standard Proofing Paper 240 and Epson Legacy Platine. We didn't have an open roll of Epson Proofing SemiMatte, but the description for this paper is very similar to the Standard Proofing Paper that we used. And, it doesn't have any OBA's like the newer proofing papers do.

The printed results on the two papers were almost identical visually, and the gamut maps of the two profiles were almost identical as well. We also tried the canned Epson profile for the Platine and it was close to our created profiles but not as exact a match as printing from the profiles that we created. Printing was done on an Epson SureColor P9000.

Tony

Tony,

Nice work done! The papers not totally identical to the OP's trial but at least the profiles up to date and made the same way.

What were the CM rendering choices, the assigned color space of the image and the image itself? Fresh delivery of the Epson Platine?

The Epson Standard Proofing Paper has more OBA though and by that a more irregular spectral plot. Spectral plots attached. Yellow plot is the Epson Standard Proofing, Red plot the Epson Platine, Blue plot the Epson Proofing White SM, Green plot the Canson Platine 2017. The last two were used by the OP.


Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots
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tastar

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #34 on: October 14, 2017, 07:47:06 am »

Re. the identical prints:

The rendering intent was perceptual, the images were sRGB images printed using the sRGB color space, the Platine was purchased in early 2016 (so it wasn't a fresh roll), the Standard Proofing was purchased in July, 2017. Profiling was done with an i1 Pro 2 with i1Profiler software. Hope that this helps.

Tony
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Doug Gray

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What a hard proof can do - and can't.
« Reply #35 on: October 14, 2017, 09:41:25 pm »

Here's what a hard proof can do:
If a hard proof and the target is illuminated at 45 degrees it will visually match viewed head on, regardless of the media, if the following conditions are met.

1. That proofed image is within the gamut of the hard proof paper.
2. If unprinted portions of the papers are masked.
3. if the proof and actual are viewed at a distance sufficient that the media texture differences are not discernible.
4. If the proof and actual have some OBAs or substrate that fluoresces then a match requires D50 including D50 uV and the profiles for both generated with M1.
5. If there are no significant OBAs then D50 with or without uV is fine and profiles can be M0, M1, or M2.
6. A match also requires no significant specular reflections which can bring out bronzing or anything that can identify either paper surface as different from each other.  Higher illumination of the proof and reference and low ambient lux level and dark clothing can accomplish this.
7. The surround and illumination levels are the same for the reference print and the proof print.

When these conditions are met, the colorimetric accuracy of the profiles is the only remaining variable and, with high quality printers and quality profiles made using the same spectrophotometer instrument it will be extremely difficult, if not impossible, to tell the proof from the reference. Even if one is a matte print and the other glossy. However, creating a hard proof on media with the same charcteristics (glossy, matte, SG, SM, etc) will improve matching when physically handling the media or where one doesn't have the control described.

However, these conditions are not often met and a proof print is NOT the same as just printing each media using Perceptual or Relative Intent even when the other conditions are met.
« Last Edit: October 14, 2017, 10:46:52 pm by Doug Gray »
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Ernst Dinkla

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Re: What a hard proof can do - and can't.
« Reply #36 on: October 16, 2017, 05:22:06 am »

Here's what a hard proof can do:
If a hard proof and the target is illuminated at 45 degrees it will visually match viewed head on, regardless of the media, if the following conditions are met.

1. That proofed image is within the gamut of the hard proof paper.
2. If unprinted portions of the papers are masked.
3. if the proof and actual are viewed at a distance sufficient that the media texture differences are not discernible.
4. If the proof and actual have some OBAs or substrate that fluoresces then a match requires D50 including D50 uV and the profiles for both generated with M1.
5. If there are no significant OBAs then D50 with or without uV is fine and profiles can be M0, M1, or M2.
6. A match also requires no significant specular reflections which can bring out bronzing or anything that can identify either paper surface as different from each other.  Higher illumination of the proof and reference and low ambient lux level and dark clothing can accomplish this.
7. The surround and illumination levels are the same for the reference print and the proof print.

When these conditions are met, the colorimetric accuracy of the profiles is the only remaining variable and, with high quality printers and quality profiles made using the same spectrophotometer instrument it will be extremely difficult, if not impossible, to tell the proof from the reference. Even if one is a matte print and the other glossy. However, creating a hard proof on media with the same charcteristics (glossy, matte, SG, SM, etc) will improve matching when physically handling the media or where one doesn't have the control described.

However, these conditions are not often met and a proof print is NOT the same as just printing each media using Perceptual or Relative Intent even when the other conditions are met.

1. I estimate that Tony met that point 1 condition and Narikin did not.
3. The media textures of the papers mentioned by the OP and Tony are very similar
4. 5. The Epson Proofing Standard paper as used by Tony has a bit of OBA and shows it in the white point. Can do without UV aware profiling I estimate.
6. Epson Proofing White Semi-Matte is not free of bronzing with some printers (Z3200 without gloss enhancer used) but may cope better with Epson printers.
    Perpendicular viewing and not too large prints will be enough with the papers described. Yes, 2000 Lux would be best for critical color viewing, going down to 500    acceptable.

7. Identical inks were used on both papers as described by OP and Tony. Observer "metamerism" caused by the inks is unlikely then.

8. addition to point 1; When both the print run paper and the paper to test/proof on have the exactly same gamut in all aspects then all kinds of CM rendering choices and images, in and out of gamut, can be used as long as they are the same for both papers.

9. addition to point 1; When the gamut of the print run paper is smaller and falls totally within the gamut of the test/proof paper then a device-link profile representing the print run paper's gamut within the test/proof paper's wider gamut can be used for the test/proof paper. For the print run paper its equivalent normal paper profile of course. CM renderings should be corresponding. Photoshop CM steps can to a degree simulate device link profiles.

10. addition to point 1; When the gamut of the print run paper is wider than etc. Forget about getting an equal print or one has to compromise on the optimal print possible on the print run paper.

10. Color appearance ........ I might use that argument when the next thread on softproofing is born again, I am usually in the camp that says it is unreliable in reproduction of originals but great when the scene photographed is 5000 miles away.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots
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Doug Gray

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Re: What a hard proof can do - and can't.
« Reply #37 on: October 16, 2017, 01:39:23 pm »

1. I estimate that Tony met that point 1 condition and Narikin did not.
3. The media textures of the papers mentioned by the OP and Tony are very similar
4. 5. The Epson Proofing Standard paper as used by Tony has a bit of OBA and shows it in the white point. Can do without UV aware profiling I estimate.
6. Epson Proofing White Semi-Matte is not free of bronzing with some printers (Z3200 without gloss enhancer used) but may cope better with Epson printers.
    Perpendicular viewing and not too large prints will be enough with the papers described. Yes, 2000 Lux would be best for critical color viewing, going down to 500    acceptable.

7. Identical inks were used on both papers as described by OP and Tony. Observer "metamerism" caused by the inks is unlikely then.

8. addition to point 1; When both the print run paper and the paper to test/proof on have the exactly same gamut in all aspects then all kinds of CM rendering choices and images, in and out of gamut, can be used as long as they are the same for both papers.

9. addition to point 1; When the gamut of the print run paper is smaller and falls totally within the gamut of the test/proof paper then a device-link profile representing the print run paper's gamut within the test/proof paper's wider gamut can be used for the test/proof paper. For the print run paper its equivalent normal paper profile of course. CM renderings should be corresponding. Photoshop CM steps can to a degree simulate device link profiles.

10. addition to point 1; When the gamut of the print run paper is wider than etc. Forget about getting an equal print or one has to compromise on the optimal print possible on the print run paper.

10. Color appearance ........ I might use that argument when the next thread on softproofing is born again, I am usually in the camp that says it is unreliable in reproduction of originals but great when the scene photographed is 5000 miles away.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots

I agree with pretty much all of that with the following observations.

Significant variation between different people's experience with the effectiveness of softproofing may be due to variation in spectral sensitivity that normally exists within the population of folks with "normal" color vision. This variation is likely more easily seen with RGB monitors than prints using different pigment inks because of the sharper spectral components of RGB monitors. It would be interesting to see more academic study in this area.

As for print media, I rather like canvas textures for certain prints but sometimes semigloss or luster. When illuminated at 45 degrees (same as the spectros that profiles are made from) I can't see any difference when in gamut and over a few meters away. Canvas being an exception in part because the 0/45 combined with the coarse texture makes for poor profile accuracy and visible color differences. Even at a distance sufficient to eliminate the canvas texture. More so with "metallic" papers.

And one can't discount psychological effects, a kind of elephant in the room.. Just knowing an image is being displayed on a monitor as opposed to room ambient alters one's perception of color in huge ways. It is easy to demonstrate and quite shocking. As large as metameric human variation in monitor color perception is these are even larger.
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GrahamBy

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #38 on: October 17, 2017, 09:33:25 am »

The numbers are great when they tell us something about say color accuracy and then a dE Metric. They are pretty awful, based on current technology available, to tell us much about color appearance.

Sorry, I don't get it. What is this "appearance" then, that is so badly measured by photometry? Doug's commentary makes sense to me, that under specified lighting conditions taking account of possible OBA's and different specular/diffuse ratios, then the numbers tell us the story. Otherwise it's a bit of a philosophy argument: "I agree with science accept when I don't like its conclusions, at which point I choose to believe whatever I feel like."

If "appearance" is so badly measured and apparently important, why should anyone give a damn about screen and print calibration?
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digitaldog

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Re: Big difference between (good) proofing paper and final print paper!
« Reply #39 on: October 17, 2017, 10:31:12 am »

Sorry, I don't get it. What is this "appearance" then, that is so badly measured by photometry? Doug's commentary makes sense to me, that under specified lighting conditions taking account of possible OBA's and different specular/diffuse ratios, then the numbers tell us the story. Otherwise it's a bit of a philosophy argument: "I agree with science accept when I don't like its conclusions, at which point I choose to believe whatever I feel like."
I have already explained below: http://forum.luminous-landscape.com/index.php?topic=120966.msg1005185#msg1005185
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