print viewing answer to customer

[randal21]

I have controlled balanced 5000k lighting and a calibrated monitor and yesterday a client said ... as she was showing me her artwork ... my colors look alittle different at my place under my artificial light and also from natural light. I explained I couldn't color match outdoors and didn't work under the flourescent lighting and had to have my controlled lighting. What would your answer have been AND am I on the right track?  Thanks.

[Scott Martin]

Excellent question. First of all, not all 5000K lighting is very good (high CRI), especially fluorescent bulbs including those found in expensive viewing booths. Solux lighting is one of the only light sources that has a super smooth tonal response throughout the entire visible light spectrum.

The fact that she says that her work looks different under daylight is significant. Daylight is our the standard lighting on our planet that we compare all others to. It's the light that humans have evolved and adapted to over millions of years.

FOr fine art purposes, I think it's smart to perform critical print viewing under a variety of conditions. Consistent high CRI lighting (that doesn't have to be 5000K - 4100K is my preferred color temp) to start with, daylight (which should be expected to vary), and incandescent (for the time being). I think it's important to be able to make work that performs well under any of these lighting conditions. Starting with the high CRI lighting is important so that you can detect and fix any imperfections that might not be as obvious under lesser quality light.  If you're able to make top notch prints, I think they'll perform well under both daylight and your high CRI lighting. You might not like the results quite as much under incandescent, but hey, that just demonstrates how crappy that light is anyways, and it's inherent limitations.

That said, for a printmaker like yourself, you have a responsibility to make prints that perform well under high quality lighting like daylight and Solux. Wither or not you want to take responsibility for making someone's images look under under poor quality lighting is up to you. Pushing people towards adopting higher quality lighting in their own environment is always good.

I view prints under these three lighting scenarios in my printmaking workshops and it's a great educational exercise that leads to great dialog. Sounds like it might instill a lot of confidence in a customer like yours. 

[Ernst Dinkla]

I have controlled balanced 5000k lighting and a calibrated monitor and yesterday a client said ... as she was showing me her artwork ... my colors look alittle different at my place under my artificial light and also from natural light. I explained I couldn't color match outdoors and didn't work under the flourescent lighting and had to have my controlled lighting. What would your answer have been AND am I on the right track?  Thanks.

Which paper and what printer has been used for the prints?

--
Met vriendelijke groet, Ernst

Dinkla Grafische Techniek
Quad,piëzografie,giclée
www.pigment-print.com

[Mark D Segal]

I have controlled balanced 5000k lighting and a calibrated monitor and yesterday a client said ... as she was showing me her artwork ... my colors look alittle different at my place under my artificial light and also from natural light. I explained I couldn't color match outdoors and didn't work under the flourescent lighting and had to have my controlled lighting. What would your answer have been AND am I on the right track?  Thanks.

I think you are on the right track, and I also think Scott's response - essentially to get the viewers up to speed looking at photos under standardized controlled lighting would be ideal. But we are often faced with the less than ideal. What if the customer won't or can't do that? Depending on the importance of maintaining such a customer under these conditions, it may be appropriate to profile and print to HER lighting conditions and keep her happy. You have no further involvement with those prints from the day she takes delivery.

[Czornyj]

...and even if the light has high CRI it doesn't necessarily has the same amount of UV, so the paper with high amount of OBA may look different in daylight than in fluorescent CCT 5000K light.

[digitaldog]

...and even if the light has high CRI it doesn't necessarily has the same amount of UV, so the paper with high amount of OBA may look different in daylight than in fluorescent CCT 5000K light.

Yup, a high CRI isn’t really a great indicator of quality. A high CRI is a decent gauge of how well a light will preform in your home but not such a great indicator of how well it will work for photography and proofing. Both a Solux 48 and a "full spectrum" tube from home depot may have a CRI of 97. I can assure you the Home Depot bulb has a giant mercury spike and some spectral dead spots.  

Interesting video: http://www.alzovideo.com/cri.htm

[John Nollendorfs]

5000 K lights were what you wanted when working with art directors and printers for art, or  photos. That way you both could be on the same page when discussing the work. But reproduction art is NOT viewed at 5000k. Most typically, it's viewed under 2800 K incandescent lighting. Best to have several different lighting situations available when dealing with art clients, and let them see the work under the situation they will display the work in.

[Mark D Segal]

5000 K lights were what you wanted when working with art directors and printers for art, or  photos. That way you both could be on the same page when discussing the work. But reproduction art is NOT viewed at 5000k. Most typically, it's viewed under 2800 K incandescent lighting. Best to have several different lighting situations available when dealing with art clients, and let them see the work under the situation they will display the work in.

This is a good example of one kind of situation I had in mind (but not in print)  in my post above - as well, much museum and gallery halogen lighting is in the 3900 range, so viewing such images under 5000K illumination they would look a bit "cooler" than the customer may find "correct".

[Scott Martin]

Yup, a high CRI isn’t really a great indicator of quality.

I think it's the best indicator of quality we've got! Unfortunately, it seems some vendors are fudging their CRI ratings. I think this is evolving...

[ComputerDork]

When is the whole CRI standard issue going to finally get "fixed"? I've noticed at the hardware store that most lightbulb boxes at the hardware megastore don't even seem to claim a CRI value at all anymore. It seems like the only way to guess at how good a light source is based on data is to look at an SPD plot.

[Ernst Dinkla]

CRI may actually slow development of new full spectrum lamps.

I usually check this site with much more measurements on lamps introduced on the market:
http://www.olino.org/us/ov/lamps

Not there yet but the big step could be a special quantum dot size filtering on LEDs:
http://www.vanderbilt.edu/exploration/stories/quantumdotled.html
were the QDs are so small they excite a broader spectrum white light right away.

This does not change the choices between warmer and colder light for different environments but "metamerism" will be somewhat reduced between full spectrum lamps versus the spiky spectral economy lamps we have today. With low OBA content papers and inksets that show less "metamerism" something can be done already to address customer's complaints. Most viewing conditions will be between 4000 and 2800K. Not that far apart if luminance is also considered with respect to the Kruithof curve.

--
Met vriendelijke groet, Ernst

340+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
update april 2012: Harman by Hahnemühle, Innova IFA45 and more

[digitaldog]

I think it's the best indicator of quality we've got!

I don’t. Because people use it incorrectly and think it tells them a lot more than it does. It is like the using Lumens for gauging what projector to get. Higher must be better (like CRI). But when you start looking at DLP projectors, that use a white filter to boost the lumens value, what you end up with an inferior quality image compared to an LCD display with a lower lumen value that doesn’t pollute colors with white. Yet people read reviews on projectors and zoom into the lumen spec which is a really bad idea until you know the type of projector making said lumens. If all you project is black text on a white bkgnd, go high lumen value and ignore the projector technology.

Again, you can find a $1 Fluorescent tube at Home Depot with a higher CRI than a bulb we know produces a better illuminant for viewing conditions. How is that higher value useful? It is useful for those in the marketing departments!

[Scott Martin]

I don’t. Because people use it incorrectly and think it tells them a lot more than it does. It is like the using Lumens for gauging what projector to get. Higher must be better (like CRI). But when you start looking at DLP projectors,

Oh god, don't get me started on DLP projectors! I've never even seen CRI values listed for any projectors. DLP sucks, LCD is better, LCoS is best for projectors.

As for the quality of *light sources* I'm still gunning for the CRI scale being the best scale we've got short of personal recommendations, reviews, etc.

Again, you can find a $1 Fluorescent tube at Home Depot with a higher CRI than a bulb we know produces a better illuminant for viewing conditions. How is that higher value useful? It is useful for those in the marketing departments!

I've actually purchased every single 4 foot fluorescent that Home Depot and Lowes sells ever year for the last four years and reviewed them for some clients. My observation is that there aren't any for $1 and bulbs with higher CRI values are almost always better than bulbs with lower CRI values, so I think this scale has value to it. Now, how accurate are they? Not always as accurate as I'd like but it seems they are getting more honest.

For example: GE Premium Cool White (F32T8) - 4100K, 86 CRI, 2950 lumens, 32 watt, T8 - available at some Lowes stores and lighting suppliers (~$3.50 per bulb) is listed as 86CRI but I'm surprised at how excellent the color rendering is when compared to Solux and Daylight. And, IMO 4100K is a great temperature to be at (and better than 5000k, IMO).

So because of my own hands-on experience helping clients evaluate lighting for their work environments, I feel the CRI scale does have value, even if its not perfect. People are obsessing over color temp and I think that misdirected attention. Nonetheless, if you could be more specific, listing part numbers and the like, I think the dialog about this could be constructive.