Non-neutral grays with R1800?

[Daniel Geiger]

Is your monitor calibrated and profiled? If you monitor is off, then it really becomes a guessing game of how to adjust the file. I use a Monaco Optix spider to do that job. Also in PS, use the "proof color" setting to get a better preview of what the image could look like, an check the "out of gamut" option as well (although desaturation should alleviate any out of gamut problems, but good to check anyway). Last but not least, the differences in color representation (additive vs. subtractive) will lead to some inconsistencies, however slight.

When I got into color printing also with an Epson R1800, I read Real World Colormanagement from Peach Pit Press, and also have the Focal Press Color Management for Photographers volume. It helped me a lot to get through all the new terminology.

I did notice when I printed some pure black & white images, that depending on ink-levels in the various colors, slight hues are introduced. Basically what you would see in warm-tone vs. cool-tone papers. Nothing I worry about, but when I compared some prints from different batches, it is quite noticeable.

Best wishes

[Bruce Watson]

Shouldn't all values with equal RGB values, though different intensities print neutral? If this is a printer "feature," it's going back on Monday.

Should they? You can make the case that they should. Will they? Often not. And yes, this is a feature of trying to print B&W images with color inks. You are trying to get the printer, driver, and inks to do something they aren't designed to do, and certainly not optimized to do, so your results shouldn't be surprising.

Many of us, when faced with similar needs, use two different printers. One for color, and one for B&W. The B&W printer gets grayscale inks designed for the duty (think MIS, Cone), and many people are using QTR to drive the printer as it is also optimized for B&W printing.

Now if you want to have more fun, take those color ink B&W images around and look at them under different lighting. It's called metamerism...

[poco]

"You are trying to get the printer, driver, and inks to do something they aren't designed to do"

While I was late in clarifying it, all I'm trying to do is print a COLOR photograph containing a neutral gray sky without parts of that sky taking on a magenta cast. Surely a color printer, using color inks, should be able to do that.

[Bruce Watson]

"You are trying to get the printer, driver, and inks to do something they aren't designed to do"

While I was late in clarifying it, all I'm trying to do is print a COLOR photograph containing a neutral gray sky without parts of that sky taking on a magenta cast. Surely a color printer, using color inks, should be able to do that.

The Epson printers using gray inks (like the significantly more expensive 2400) will do a better job of this than a printer without a gray ink like the 1800. Good neutrals are hard to create using the inks that the 1800 has available.

[Helen Bach]

Poco,

I printed this picture of the interior of Peter Eisenmann's House VI on my R800 as a test. I used the canned profile for Epson Premium Glossy Photo, with the 'Best Photo' setting - which is what the profile was written for (SPR800 PremGlossy BstPhoto.icc). It wasn't perfect, but it was fairly close. I'd be happy to post it to you tomorrow morning for comparison if you PM me with your address.



Which version of Photoshop are you using?

Bruce,

"Now if you want to have more fun, take those color ink B&W images around and look at them under different lighting. It's called metamerism..."

If that property, which used to be called colour constancy or inconstancy, is now called metamerism what do we now call the property that used to be called metamerism? This is a genuine question, not a snide remark - I realise that the meaning that you give to metamerism is widespread in this fresh-fangled digital printing business.

Best,
Helen

[poco]

Helen,

I'm in the dark ages with Photoshop 6.

PM sent, and nice subtle shot.


-Michael

[Ken Lee]

As Daniel Geiger says, unless you are using a completely calibrated and profiled workflow, it's a guessing game - and that's putting it politely. I'd call it "maddening" instead.

You can get a custom profile from inkjetart.com for much less than the cost of the paper you have/will already wasted. The profiles you get from Epson are OK, but keep in mind that grey is the hardest tone to reproduce.

[Helen Bach]

With printers like the R800 and 2100/2200 it can take some effort to improve on the Epson profiles, particularly with the rendering of greys, if you are using the correct paper and ink combination and the right media and resolution settings. Before settling on Profilemaker 5 I tried a few well-known profiling services and then the PrintFix Pro, and often found that they couldn't beat the Epson profiles for neutrality.

Nobody is suggesting that perfection is possible, but acceptable deviation might be within reach. Of course, if you know you are going to deviate, al least you should choose the side to wander off to.

Photoshop 6 should be OK for colour management as far as I know - I still use it on one of my computers and it happens to be the general purpose one that is connected to the R800. I used PS6 for the test print I'm about to send you, so our software, printer, paper and ink should match. Well, apart from the old R800 / new R1800 difference.

Because you really have to micromanage some of those easily-distracted Epson consumer printers into doing a proper job, I'd suggest using a larger number of patches for profiling than would be adequate for better-behaved (more expensive) printers. There's a four-page target with 1452 patches that has a good set of neutral patches (those all have R = G = B and you don't need a profiled monitor to tell you that that should print neutral) that I could send you if you wished to try a custom profile. First let's see how your printer compares with my old R800.

Best,
Helen

[Bruce Watson]

If that property, which used to be called colour constancy or inconstancy, is now called metamerism what do we now call the property that used to be called metamerism? This is a genuine question, not a snide remark - I realise that the meaning that you give to metamerism is widespread in this fresh-fangled digital printing business.

I was indicating a condition called "illuminant metamerism" in which a given sample will show variance in color depending on the spectral power distribution of the light source.

What I remember about "color constancy" is that the term is used mostly in discussions of how the human eye/brain system perceives color, and describes how the eye/brain system keeps perceived color constant in changing lighting conditions. For example, a red truck driving from sunlight into shadow continues to register as the same red even though the actual reflected spectrum has changed.

[Helen Bach]

I was indicating a condition called "illuminant metamerism" in which a given sample will show variance in color depending on the spectral power distribution of the light source.

What I remember about "color constancy" is that the term is used mostly in discussions of how the human eye/brain system perceives color, and describes how the eye/brain system keeps perceived color constant in changing lighting conditions. For example, a red truck driving from sunlight into shadow continues to register as the same red even though the actual reflected spectrum has changed.

That's how I understand colour constancy as well: the degree to which a colour appears to be the same under different lighting conditions. If it doesn't look the same, it exhibits colour inconstancy. So if something looks neutral in one type of illumination and green in another, it can be said to exhibit colour inconstancy.

My understanding of metamerism is that defined by the CIE in the CIE International Lighting Vocabulary: spectrally different colour stimuli that have the same tristimulus values. The corresponding property is called metamerism. (ie two different materials that appear to be the same colour although they don't have the same spectral characteristics. The entire field of colour reproduction depends on metamerism.) For example a painted wall and a photograph of the wall that has been colour matched to the wall can be said to be an example of metamerism. Under the CIE definition, the greater the degree of metamerism the more they look alike under different illuminants. What you call metamerism, others would call metameric failure.

Best,
Helen