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bjanes

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Rant 23
« Reply #140 on: October 10, 2009, 02:59:38 pm »

Quote from: Jack Flesher
Bottom line is your chosen printer/paper combo's gamut is pretty narrow.  This is not inherently bad, especially if you like the result, but relevant to this discussion as it limits what you can lay down in on a print.  The fact that your monitor matches it simply indicates that the monitor is equal to or perhaps slightly larger than the paper/ink you use.  However it does not mean your monitor can accurately render the gamut of a larger paper/ink combo.

On another tack, given what you've stated about your satisfaction with your prints and monitor, you could probably take up a total sRGB jpeg workflow from capture to output and not lose much of anything at all to a 16-bit raw workflow; your needs simply don't require a larger gamut.   Huge workflow convenience advantage for you as it would eliminate the entire raw conversion process.  Heck, I'm actually a little jealous of that!

Cheers,

Jack's dismissive reply to Ray ignores a few relevant facts. In fact, the sRGB gamut will clip blues, greens and yellows that are in gamut for his printer as shown in the gamut plot below. Ray is justified in using ProPhotoRGB to preserve those colors. He previously mentioned he likes the yellows that are preserved in ProPhotoRGB; those would be lost if he used sRGB as his working space.

[attachment=17113:Epson7600vs_sRGB.png]

Of course, one is not interested in gamut plots which show what could be in an image but rather with what colors are actually in one's image. The plot below demonstrates the gamuts of the printer test image, sRGB, and the 7600 printer with Premium Lustre paper (using the profile from a local lab that uses the printer). Note the yellows that are clipped in sRGB but are within the gamut of the printer. Another 3D view could have shown the greens with a similar gamut mismatch. The printer can print saturated greens and yellows at mid-luminance that are out of the sRGB gamut. Of course, a reflection print can not print low luminances because of its limited DMax, especially with art papers with a limited DMax, but some of these can be shown on the sRGB screen because of the gamut mismatch.

[attachment=17117:7600_sRG...estImage.png]

Then one should ask which colors in the test image are out of gamut for the printer and how does affect the image. The GamutVision plot below shows the ΔEs for various parts of the image. A ΔE of one represents a just noticeable difference and a ΔE of 5 may not significantly impair the image, but this is only a rough guide and varies with images and viewing conditions. The largest ΔEs are in the patches with high luminance saturated colors which do not occur in the real world part of the image, but which could occur if you are taking night pictures of neon lights on Times Square or the Ginza or in some landscapes with bright colors in flowers. Other large ΔEs occur in the low luminance areas of the image that can't be printed with a limited DMax. In the most important regions of the image (e.g. straw berries and skin color) the ΔEs are 5 or less and even in the sunset the ΔEs are relatively low in the higher luminance colorful areas of the image.

[attachment=17121:7600_GamutVision.png]

Even if you clip the test image to sRGB as Jack suggests, there are still a lot of out of gamut colors. However, some colors that could have been printed are lost.

[attachment=17122:7600_Gam...ion_sRGB.png]

With the x900 printer and the EFP (exhibition fiber) paper, the situation is much improved, but there are still a lot of out of gamut colors. Note that the scale has changed with this analysis.

[attachment=17123:9600_gamut.png]

I hesitate to state that I am still using the Epson 2200 and this thread has convinced me it is time to upgrade. Since I don't have a MFDB, I don't print at very large sizes and the 3880 or 4880 might be a good choice for my needs. I understand that Michael will review the former soon. However, I understand that these printers waste ink if you need to change blacks. My monitor's gamut does not cover all of sRGB, so a monitor upgrade would also be a good idea. However, even the high end Eizos that would cover Adobe RGB could not show the gamut of the printer and I might defer that purchase until LED monitors which offer more flexibility in calibration are available at reasonable prices. Any comments or suggestions?





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Jack Flesher

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Rant 23
« Reply #141 on: October 10, 2009, 09:37:18 pm »

Quote from: bjanes
Jack's dismissive reply to Ray ignores a few relevant facts. \

SNIP

demonstrates the gamuts of the printer test image,  sRGB, and the 7600 printer with Premium Lustre paper (using the profile from a local lab that uses the printer).

And as is usual, your post ignores facts actually pertinent to the discussion we're having -- like the one that Ray prints on MATTE paper with Mk ink on his 7600, NOT Epson Premium Luster and Pk ink...
« Last Edit: October 10, 2009, 09:40:26 pm by Jack Flesher »
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Ray

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Rant 23
« Reply #142 on: October 11, 2009, 12:29:58 am »

Quote from: Jack Flesher
And as is usual, your post ignores facts actually pertinent to the discussion we're having -- like the one that Ray prints on MATTE paper with Mk ink on his 7600, NOT Epson Premium Luster and Pk ink...


However, Jack, as I've mentioned a couple of times, the ProPhoto print of your test image on my Enhanced Matte does show a more golden yellow than the sRGB print, and does show a clear differentiation between the first two shades of green squares and between the two cyan squares. In the sRGB print those two green and two cyan squares look like the same shade of green and the same shade of cyan, and furthermore, those differences are equally apparent in the preview on my monitor with proof colors enabled.

Since your test image was printed 'as is' with no adjustments whatsoever, it makes no difference what monitor I use. I could print the image from an uncalibrated laptop and the print should look the same. What counts for editing purposes is the closness of the match between the preview on the monitor and the resulting print.

Now the fact is, I have a sufficiently close match using Enhanced Matte, so a better monitor would serve no purpose with my current printer and paper. Whether it would serve a purpose with another paper type with a wider gamut, such as Premium Lustre or Premium Glossy, is another matter which I cannot conveniently test right now because of the ink-swap hassle. However, I have used one roll of Premium Glossy and a couple of rolls of Premium Lustre in the past, before I switched to Enhanced Matte. In fact, I recall I was using Prm Lustre when I bought the Eye-One colorimeter. I bought an Eizo FlexScan S1910 monitor at the same time because it was 'on special' and because I thought an LCD monitor would be less strain on the eyes and because I thought I might get a better calibration if my old Sony CRT proved to be lacking.

It so happened that the 'easy' automatic option in the iMatch software produced such a close match on my old CRT, with the Prm Lustre I was using at the time, that I saw no reason to set up the FlexScan.  I don't have enough time to play with toys. I have a practical orientation towards photography. What works, works, sometimes despite the theory stating it shouldn't. However, if I were to revisit the situation with Prm Lustre and 'pixel-peep' the subtle shading in your test image, I'm prepared to accept I might see subtleties in the print which are not, and cannot be, visible on my monitor.

I'm getting close to the end of my matte black ink and current roll of matte paper. After whichever runs out first, I'm going to switch to Premiem Gloss and Photo Black ink, but at present I'm rather busy doing the tiling in my new house. It's a very, very tedious job (perhaps because I'm such a perfectionist). I'd rather print test images.  
« Last Edit: October 11, 2009, 03:37:18 am by Ray »
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Ray

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Rant 23
« Reply #143 on: October 11, 2009, 02:58:27 am »

Quote from: tho_mas
ah, okay, I've confused that. Sorry.

Problem here is what I've mentioned above.
Paper white in paper profiles is often blueish/grayish - at least if the profiles are measured by devices without UV cut filter.
This is due to optical brighteners in papers (not all papers of course, but most photographic papers contain optical brighteners).
But blueish white is not white. It is not only bluer than white it's at the time darker than white.
But your Paper is visually … white.
What happens with your softproof if use paper simulation?
I've taken the profile a FUJI paper (RGB printer / C-print) because these papers contain a lot of optical brighteners so the problem is quite obvious.

This is crop from a sky with clouds - screenshot of the original file:
[attachment=17097:01_sp_off.jpg]

This is the file with softproof relative colormetric + BPC / simulation of black ink:
[attachment=17098:02_sp_rcm_black.jpg]

This is the file with softproof relative colormetric + BPC / paper simulation.
Due to the relative colorimetric RI you can see quite well the blueish white of the paper - and it's darker.
[attachment=17099:03_sp_rcm_paper.jpg]

This is the file with softproof absolute colorimetric / simulation of black ink.
Color management spins the blueish paper white to the warmer white point of the display.
(too, the contrast range is compressed to the level of the paper contrast but is displayed at the luminance level of the monitor - so no compenstion).
[attachment=17100:04_sp_acm_black.jpg]

This is the file with softproof absolute colorimetric / paper simulation:
[attachment=17101:05_sp_acm_paper.jpg]

In the last screenshot the white point compensation works fine so far but where are the transitions of the clouds?
They are suppressed on the monitor preview - but they are visible in the print (as in screenshot #2).
The blueish (and therefore darker) white (which is nothing else than a measurement device error) compresses the transitions in bright tonal values.
You'll find the same effects of compression all over the tonal range of the image… just less obvious in less bright tones.
This effect is clearly visible with papers containing a high amount of optical brighteners and less visible in papers with a small amount of optical brighteners - but still there.
This is why it is not a bad idea to calibrate the monitor to paper white (both luminance and white point) and set the softproof to relative colorimetric RI + BPC (or perceptual RI) and simulation of black ink only - the monitor white already matches paper white so there's no reason to adapt white points for the preview.


Tho_mas,
Interesting comparisons! Correct me if I'm wrong, but your suggestion of calibrating the monitor to the paper white would cause images edited on such a monitor to be inappropriate for other purposes, such as viewing web images or converting images to sRGB for viewing on one's plasma TV, would it not?

I've opened your original clouds' image using 'simulate paper color', and the result I get on my monitor is quite different to your version of paper simulation. Quite different! I've placed the 3 images side by side in a new document so you can compare easily. The first one, top left, is is my rendition of your original image in my proof setup. I do not see the bluish white of the paper that's clearly evident in your 'paper color simulation'.

[attachment=17126:Tho_mas_clouds.jpg]

When I try the 'advanced option' when calibrating with Eye-One, I find that extracting the paper-white values from the Bill Atkinson profiles is not possible. I get the impression I would have to buy an X-rite spectrophotometer to create my own profiles in order to do this.

If I select D65 as a white point in 'advanced mode', the monitor calibration simply does not match the print when softproofing, so what's the point of the advanced option in my situation? The easy (automatic) option produces a near-perfect match.

I mentioned that the dark grays visible on both print and monitor preview, match exactly. The same cannot quite be said for the lightest grays. In that respect, my matte paper slightly exceeds the performance of the monitor, but so slightly it's not an issue. On Jack's test image, the brightest gray, 254, is completely lost on my monitor preview, in soft-proof mode (whether simulate paper color or black ink). 253 is so faint it's effectively lost, but 252 is definitely noticeable, although faint.

However, on the print, if one holds the print at the right angle against the light, there's a slight hint of both 254 and 253. The implication here is, if I were to print out some cloud images like your examples above, the print should reveal a very small increase in subtle shading in such clouds, compared with my monitor preview.

The bottom line here, surely, is that all that counts is the match between print and monitor preview. If the print is very slightly better in some regard than the monitor preview, that's fine by me. If the print is worse than the monitor preview, that's not good. The fact that subtle shading in the sky is lost with Absolute Colorimetric rendering is not necessarily a problem. One just selects the sky, in soft-proof mode, and darkens it.

I use whatever rendering intent produces the best result to my taste. Sometimes I use Saturation Intent for photographic images, even though such rendering intent is usually recommended only for pie charts. I'm often confronted with out-of-gamut colors and I take some trouble to select such areas that are out-of-gamut and bring them back into gamut by reducing saturation or lightening or darkening the specific areas.

Incidentally, the temperature of my calibrated monitor seems unusually high at 7600K, although the luminance seems okay at 94.3 nits. The minimum luminance is 0.0 cd/m2, presumably because CRTs have no backlight.

Our monitors would clearly seem to be calibrated differently, but I repeat, what counts in the final analysis is the match between print and monitor preview.

By the way, the profile I sent you for analysis was probably a bit old, July 2009. Eye-One's reminder is every month at a minimum (edit: at a maximum. I too can get things things the wrong way round   ). I considered this too tedious and unnecessary. There should be an option for 'every 2 months', but perhaps 3 months is too much. With a re-calibration, the following image shows a more noticeable difference between the two greens in the lower half of the image.

Red, yellow and green are quite different in the upper half, on monitor and print, but bear in mind that all out-of-gamut colors in this image were brought back into gamut before printing. Beware! ProPhoto RGB profile embedded.

[attachment=17127:LL_sRGB_...to_space.jpg]
« Last Edit: October 11, 2009, 05:22:58 am by Ray »
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tho_mas

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Rant 23
« Reply #144 on: October 11, 2009, 06:57:56 am »

Quote from: Ray
Correct me if I'm wrong, but your suggestion of calibrating the monitor to the paper white would cause images edited on such a monitor to be inappropriate for other purposes, such as viewing web images or converting images to sRGB for viewing on one's plasma TV, would it not?
No, why? Basically you adjust the white point of the monitor to a color temperature you consider as a neutral white under given lighting conditions.
Now, if you watch TV the TV might look a bit blueish first but you're adapting to the white point of the TV after a few minutes.
Example: you are working at your monitor in the evening. Now you make a break for a cup of tea in the kitchen (with tungsten light) and read a magazine. You'll consider the paper of the magazine yellowish. But after some minutes (15minutes or so) you are adapted to the tungsten light and you'll consider the magazine paper as white. Now you return to the monitor and in the first moment you'll think - shit, what a blueish soup. After some minutes you will adapt to the monitor white again. This is the basic principle.
As to web/sRGB: the white points in the profiles don't change the appearance of an image - they are just referring to the illumination of the PCS.
If you convert white of ProPhoto (5000K) to sRGB (6500K) it's still RGB 255-255-255… so white.

But… calibrating to paper white under controlled viewing conditions implies that the calibration is okay for a certain range of papers but maybe too warm or too cold for other papers.
Within the range of photographic papers I'd say just calibrate to your preferred paper and it will be quite okay for all the other papers as well (as a long as you don't use paper simulation).
You can take a sheet of offset print paper type 1 or 2 (glossy/matte coated) as well - it's quite a good average.

When viewing printed images you're adapting as well - you're adapting to the color temperature of the brightest ambient light source (always). So you'll consider paper white as a neutral white under the lighting conditions you are viewing the images in.
Only if you compare two papers side by side you'll notice the different white points of these papers.

Quote
I've opened your original clouds' image using 'simulate paper color', and the result I get on my monitor is quite different to your version of paper simulation. Quite different!
you are trying to reproduce the "theory" and that's fine. Theory is useless if it doesn't reflect reality. But did you get what I was showing with my examples, did you get the principle? If yes, you should know why it is looking so different with your paper profile on your monitor.
Your softproof darkens the print preview too much and it looks gray. But in fact printed the sky is blueish (with a very slight nuance towards purple). This file has been printed as C-print (semi matte and glossy and metallic), on Innova Fiba ultra smooth and as CMYK print (coated paper). On all these prints the sky is always blueish - without any editing of the sky's color prior to printing. It has never been gray and it wouldn't be gray on your paper as long as your printer profile and the color management is accurate.
Actually I think it's quite easy: if the monitor white already matches paper white (white point and luminance) - why should colormanagement spin the white point and darken the image then?
And as to the contrast range of the printer/paper this is reflected in the simulation of "black ink".
The term "black ink" is a bit misleading - actually they should name it "relative colorimetric preview (of the softproof on the monitor)".

Quote
When I try the 'advanced option' when calibrating with Eye-One, I find that extracting the paper-white values from the Bill Atkinson profiles is not possible
no, no, no… forget the values!
Eye up the paper under controlled lighting conditions and adjust the white point and luminance of your monitor manually! Then calibrate to the "native white point".

Quote
Incidentally, the temperature of my calibrated monitor seems unusually high at 7600K
yes, that's very high.

Quote
The minimum luminance is 0.0 cd/m2, presumably because CRTs have no backlight
forget it! This is a mismatch of the i1-display and the i1-Match software. Colorimeters are inaccurate at very low levels.
Set up your monitor in a dark room an switch it on. It's not pure black.


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Ray

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Rant 23
« Reply #145 on: October 11, 2009, 07:22:05 am »

Quote
No, why? Basically you adjust the white point of the monitor to a color temperature you consider as a neutral white under given lighting conditions.
Now, if you watch TV the TV might look a bit blueish first but you're adapting to the white point of the TV after a few minutes.
Quote

No. I'm not so much interested in adaption after a periodof time. An exact match between monitor and print is what counts. In a period of time, the print fades and all bets are off.

Again, you're not making much sense. An exact match between monitor and print is all that counts. I have it, outside of extreme pixel-peeping.
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tho_mas

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Rant 23
« Reply #146 on: October 11, 2009, 07:51:37 am »

Quote from: Ray
No. I'm not so much interested in adaption after a periodof time.
you didn't get what I was trying to explain. The comparision of monitor view and print view has to match immediately - this is why you should edit and eye up prints under controlled lighting conditions.

Quote
An exact match between monitor and print is all that counts.
of course. This is why you need controlled viewing conditions - e.g. a viewing booth. And this is why it is a good thing if monitor white matches paper white in the viewing booth.
If you don't work under controlled viewing conditions that's fine... but then we don't have to discuss any further. At least not about a "match" of monitor preview and print.
Here on the forum you might search for contributions of "digital dog" who is a reputable expert of CM. I think he's working the way I do or at least similar.
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Ray

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Rant 23
« Reply #147 on: October 11, 2009, 10:46:03 am »

Quote from: tho_mas
you didn't get what I was trying to explain. The comparision of monitor view and print view has to match immediately - this is why you should edit and eye up prints under controlled lighting conditions.

of course. This is why you need controlled viewing conditions - e.g. a viewing booth. And this is why it is a good thing if monitor white matches paper white in the viewing booth.
If you don't work under controlled viewing conditions that's fine... but then we don't have to discuss any further. At least not about a "match" of monitor preview and print.
Here on the forum you might search for contributions of "digital dog" who is a reputable expert of CM. I think he's working the way I do or at least similar.


No! no! no! You are being totally anal.

Peoeple don't view their prints in a viewing booth. They view them on their walls in their houses, in normal daylight and in the evening with artificial lighting.

I've mentioned before, the reflective quality of prints results in their appearance changinging throughout the day and evening depending on the ambient lighting conditions. This is one of the properties of the print which is different from the monitor.

I never adjust what my eyes tell me to a theory of what they should see. I wouldn't know how.
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tho_mas

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Rant 23
« Reply #148 on: October 11, 2009, 10:52:17 am »

Quote from: Ray
Peoeple don't view their prints in a viewing booth. They view them on their walls in their houses, in normal daylight and in the evening with artificial lighting.
is that so? That is totally new to me. Now I'll rethink my entire workflow. Thanks for the insights.
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Jack Flesher

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Rant 23
« Reply #149 on: October 11, 2009, 10:55:29 am »

Quote from: Ray
Now the fact is, I have a sufficiently close match using Enhanced Matte, so a better monitor would serve no purpose with my current printer and paper.

And why I said earlier, that is great for you!  Seriously, it sounds like you are content with your present printer/paper and monitor combination and no upgrade is needed, which is truly awesome for you.  However, none of that alters the fact that your particular setup is also leaving a lot of the total color and DR capability of your camera unused...  

Happy shooting and printing!  
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bjanes

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Rant 23
« Reply #150 on: October 11, 2009, 11:00:32 am »

Quote from: Jack Flesher
And as is usual, your post ignores facts actually pertinent to the discussion we're having -- like the one that Ray prints on MATTE paper with Mk ink on his 7600, NOT Epson Premium Luster and Pk ink...


Even so, with Enhanced Matte and MK ink, some yellows are in gamut for the printer and out of gamut with sRGB, which comports with Ray's observations, which you have ignored. Also, some greens are in gamut for the printer and out of gamut for sRGB. Ray apparently knows what he is doing.  My original assertion holds. I don't have a profile for the 9600, so I used one for the Epson 2200, which has a similar gamut, likely not superior to the more expensive x600.

[attachment=17133:Epson220...dMatteMK.png]
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Ray

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Rant 23
« Reply #151 on: October 11, 2009, 11:10:45 am »

Quote from: Jack Flesher
And why I said earlier, that is great for you!  Seriously, it sounds like you are content with your present printer/paper and monitor combination and no upgrade is needed, which is truly awesome for you.  However, none of that alters the fact that your particular setup is also leaving a lot of the total color and DR capability of your camera unused...  

Happy shooting and printing!

Watch this space when I change to Prm Gloss   .
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Ray

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Rant 23
« Reply #152 on: October 11, 2009, 11:32:09 am »

Quote from: tho_mas
you didn't get what I was trying to explain. The comparision of monitor view and print view has to match immediately - this is why you should edit and eye up prints under controlled lighting conditions.

of course. This is why you need controlled viewing conditions - e.g. a viewing booth. And this is why it is a good thing if monitor white matches paper white in the viewing booth.
If you don't work under controlled viewing conditions that's fine... but then we don't have to discuss any further. At least not about a "match" of monitor preview and print.
Here on the forum you might search for contributions of "digital dog" who is a reputable expert of CM. I think he's working the way I do or at least similar.

It does match immediately, although it's better to wait a few minutes for the ink to dry and settle in. When I compare print with monitor, it's either in a day lit room or, under the same artificial lighting from an energy-saving, cool-daylight bulb.
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Ray

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Rant 23
« Reply #153 on: October 11, 2009, 11:33:54 am »

Quote from: tho_mas
is that so? That is totally new to me. Now I'll rethink my entire workflow. Thanks for the insights.

No need to rethink your workflow as long as you've got that perfect match between monitor preview and print, as I have.
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Jack Flesher

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Rant 23
« Reply #154 on: October 11, 2009, 01:05:55 pm »

Quote from: Ray
No need to rethink your workflow as long as you've got that perfect match between monitor preview and print, as I have.

I think Thomas was being sarcastic Ray .  Your methodology works for your particular paper, profile, printer and monitor, and since that's all you use, it works -- a classic case where your particular combination of wrongs happen to cancel each other out and make a right    

However, you'll likely be screwed with any paper change.  OTOH, Thomas' workflow is a proper CM workflow and he (along with everybody else that uses same) can switch between papers or even printers without significant issues.

Again, happy shooting and happy printing!
« Last Edit: October 11, 2009, 01:26:01 pm by Jack Flesher »
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Ray

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Rant 23
« Reply #155 on: October 11, 2009, 06:12:49 pm »

Quote from: Jack Flesher
However, you'll likely be screwed with any paper change.  OTOH, Thomas' workflow is a proper CM workflow and he (along with everybody else that uses same) can switch between papers or even printers without significant issues.

Well, I can't argue with that, yet, because it's so troublesome for me to change papers right now and I haven't got the time. However, I don't see any better alternative calibration options that are available to me. The iMatch software doesn't allow me set the paper-white as a target, from the Bill Atkinson profiles I use. As I've mentioned already, I was using Prm Lustre without any calibration problems (that I recall) before I tried the matte paper. However, I do recall having one or two slight issues with previous equipment using ColorEyes software with an x-rite DTP94 colorimeter and a Viewsonic 19" CRT monitor on an older WinXP 32bit system.

However, far more problematic than any calibration mismatch was a tendency of the yellow ink in my 7600 printer to become contaminated with cyan which normal head-cleaning routines didn't fix. As a work-around I resorted to extending the canvas of the first print in each session and placing a pure yellow band at the top. I'm pleased the problem has now disappeared. I believe the contamination was in the nozzle caps.
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tho_mas

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Rant 23
« Reply #156 on: October 11, 2009, 06:26:50 pm »

Quote from: Ray
The iMatch software doesn't allow me set the paper-white as a target, from the Bill Atkinson profiles I use.
the values would be useless in any case. Do you atually read was others write?
u-s-e   y-o-u-r   E-Y-E-S ... or can't you tell white from white?
« Last Edit: October 11, 2009, 06:27:10 pm by tho_mas »
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Ray

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Rant 23
« Reply #157 on: October 11, 2009, 07:22:09 pm »

Quote from: tho_mas
the values would be useless in any case. Do you atually read was others write?
u-s-e   y-o-u-r   E-Y-E-S ... or can't you tell white from white?

Now you are becoming insulting. This is what Chavez and Blatner, in their book on CS4, have to say about Simulate Paper Color and Simulate Black Ink.

Quote
Checking Simulate Black Ink turns off the black-point compensation, while checking Simulate Paper Color makes Photoshop use absolute colorimetric rendering instead, forcing the printer to reproduce the actual "paper white" and actual "ink black" of the simulated proof.

If you're printing to a low-dynamic-range process, such as newsprint or inkjet on uncoated paper, Simulate Black Ink will give you a much better idea of the actual blacks you'll get in print.

I would not describe Epson Enhanced Matte as newsprint or uncoated inkjet paper.
« Last Edit: October 11, 2009, 07:29:17 pm by Ray »
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bjanes

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Rant 23
« Reply #158 on: October 11, 2009, 07:43:35 pm »

Quote from: Jack Flesher
I think Thomas was being sarcastic Ray .  Your methodology works for your particular paper, profile, printer and monitor, and since that's all you use, it works -- a classic case where your particular combination of wrongs happen to cancel each other out and make a right    

However, you'll likely be screwed with any paper change.  OTOH, Thomas' workflow is a proper CM workflow and he (along with everybody else that uses same) can switch between papers or even printers without significant issues.

Again, happy shooting and happy printing!

Sarcasm and condescension are not welcome in this forum, but abound in some quarters.  

Thomas matches the monitor white point to the paper color in his viewing booth, and this is suggested as the proper workflow if I interpret Jack's comment correctly. However, there are other viewpoints. In Color Management, Second Edition, by Bruce Fraser, Chris Murphy, and Fred Bunting, it is suggested to set the white point to 6500K, adjust the luminances of the monitor and viewing booth to the same level, and deal with the color of paper white in the profile. However, they do allow that some people working in extremely color critical environments and having complete control over all variables may want to adjust the white point of the monitor to match a sheet of paper in the viewing booth. What type of paper is not specified. These conditions are not met by most non professional photo enthusiasts. I don't know what setup Ray uses, but my "viewing booth" is a Solux lamp, and I won't attempt to enter the rarefied world of Thomas and Jack.  

Bruce and colleagues note that a CRT allows changing the white point by varying the RGB channels, but it may not operate optimally at a lower white point. With LCDs, the white point has to be adjusted in a look up table unless you are using a model with separate red, blue and green LEDs for the backlight. With an 8 bit LUT, the gamut of the monitor will be compromised. I would be interested in what our resident experts think of the advice given by Bruce et al.
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tho_mas

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Rant 23
« Reply #159 on: October 11, 2009, 07:52:24 pm »

Quote from: Ray
Now you are becoming insulting.
I've mentioned the visual match of paper and monitor white several times. You seem to ignore this. Too, I explained why the measurement with certain papers (especially those used for photgraphy, namely literally all semi glossy or glossy papers) leads to a blueish/grayish representation of white in those profiles.

Quote
Checking Simulate Black Ink turns off the black-point compensation, while checking Simulate Paper Color makes Photoshop use absolute colorimetric rendering instead, forcing the printer to reproduce the actual "paper white" and actual "ink black" of the simulated proof.
The first part (simulate black ink turns off the BPC) - in my reading - is nonsense. In fact it enables BPC for the preview on the monitor.
If you don't trust me, try it yourself. Look at an image (Jack's printer test) without softproof. Now enable softproof with rel.col RI + BPC and only with "black ink" for the preview: the dark tonal values will be displayed brighter (and less contrastier). Why? Because the black point of the paper (of the target profile) is reflected for the preview on the monitor. With "black ink" disabled the (rel.col+BPC) softproofed image is displayed within the contrast range of the monitor.
Too, as with "paper simulation" the "black ink" simulation is selected simultaniously that would mean - in the consequence of what they are saying - that BPC for the preview would be turned off as well. Doesn't makes sense to me... other than there a misreading due to language barriers.
Now as to paper simulation... in theory that's all great. Above all: in theory it's true. The problem is the (real world) measurement of certain media. Photographic papers often contain, I repeat myself, optical brighteners. Optical brighteners reflect UV light as bluesih. So the actual white is recorded as a light blue in the profile. And therefore at the same time darker than white. See my post #141.

You can make your own proof: adjust the display to the white of the paper - so that the monitor white matches the paper white under your prefered viewing conditions visually.
Now white is white. Not warmer nor colder but the same. Not darker nor brighter, but the same.
Now you enable paper simulation and the white changes. At the latest now you must wonder what is going on - the monitor already matched the paper white; if the white changes duee to "paper simulation", it simply can't be "true".

« Last Edit: October 11, 2009, 08:02:34 pm by tho_mas »
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