Posted by Elaine Becker on Wed, Apr 28, 2010
CyberChrome Inc was an exhibitor at the recent American Coatings
Show in Charlotte, NC. Featured products included OnColor Profiler for improving inter-instrument agreement and the OnColor Suite of color management software for quality control and color formulation.
According to the press release from the American Coatings Society, "With 328 exhibitors and about 6,700 overall participants (2008: 331 / 5,600), the second edition of the American Coatings Show & Conference was hugely successful as the highlight event of the US paint and coatings industry. The combination of trade show and conference, held April 12-15, 2010 at the Charlotte Convention Center, North Carolina, thus once again exceeded all expectations."
Attendees came from not only North and South America, but there was a strong presence from Asia as well. Visitors at the CyberChrome booth included many US companies but also companies from Canada, Mexico, India, China, and other Pac Rim countries.
Interest in instrument profiling was high as companies struggle to manufacture to the same electronic color standards with tight color tolerances around the world. OnColor Profiler helps to meet the objective by providing much tighter inter-instrument agreement and allows them to meet the rigid color tolerances demanded in today's market.
Many larger companies are also interested in placing color matching systems at their distributor locations where they can match their own custom colors and reduce the burden on the color lab at the main facility. It also allows distributors to turn around custom matches in a much shorter time. CyberChrome's Match Express software provides an affordable and easy to use software package for distribution locations.
While attendance was "decent" at this show, exhibitors and attendees both wonder about the future of trade shows such as this one. With internet meetings, webinars, and the high costs of travel, it seems like fewer and fewer people attend these shows. There is still much to be said for face to face meeting, ralationship building and the social interaction that happens at events like this. What are your thoughts on attending trade shows in the future?
Posted by Elaine Becker on Thu, Apr 08, 2010
This blog article was written by Dr. John W. Root of Mt. Baker Research:
A translucent solid is not perfectly opaque. Part of the light incident on it penetrates the surface where it undergoes internal scattering and lateral diffusion away from the entry point. Both processes reduce the intensity of reflected light.
Because of lateral diffusion, the reflectivity of a translucent solid decreases as the size of the instrument's sample port is reduced. This effect causes systematic errors in measured spectral reflectance factor ("SRF") data. The magnitude of these errors depends on the following: (1) Instrument geometry. (2) Characteristics of sample surface. (3) Sizes of illuminated and measured areas of sample.
Measurement of Translucency
In commercial spectrophotometers that support diffuse illumination, the entire exposed surface of the sample is illuminated and an optical system controls the area viewed by the detector. Over-illumination is achieved by configuring the viewed area to be smaller than the illuminated area. Experiments in which over-illumination is varied can be used to measure the fractional reflectance losses ("FRL") that result from lateral diffusion. The author recently used this technique to measure FRL values for many ceramic tiles, glasses, and plastics.
The X-Rite ColorEye 7000A ("CE7000A") spectrophotometer supports a wide range of over-illumination. Maximum over-illumination is achieved with the LAV/VSAV configuration in which the LAV sample port is combined with the VSAV lens setting. The VSAV/VSAV configuration minimizes over-illumination.
The typical FRL results reported below were calculated from SRF data measured using the LAV/VSAV and VSAV/VSAV configurations of a recently purchased CE7000A (S/N 37132651108). The success of this method requires that the instrument's white calibration tile exhibit negligible translucency. This was the case for the author's new CE7000A, but not for his 2nd instrument (S/N 37116190602).
Translucency in Transfer Standards
The author's tests demonstrated that many optical materials exhibit translucency. For the FRL values listed below the 2σ standard error of estimate is ± 0.03%.
Typical Values: White Carrera® glass, 25.6%. Extruded Teflon®, 22.9%. White Vitrolite® glass, 18.9%. Ceram red-orange 99/1 tile, 8.98%. Sintered PTFE powder (Fluorilon® and Spectralon®), 3.6% - 2.9%. Ceram red tile, 3.14%. MC-20 Russian white opal glass, 3.13%. Ceram orange tile, 3.03%. Ceram yellow tile, 2.52%. X-Rite white calibration tile (S/N 37116190602), 1.43%. Konica-Minolta CMA103 white tile (S/N 18776042), 0.90%. X-Rite white calibration tile (S/N 37132651108), 0.00%.
Although FRL values may be measured using other instruments, the results will depend on the translucency of the instrument's white calibration tile as well as the dimensions of its LAV and VSAV sample ports.
Comparisons of SRF data measured using instruments with large vs. very small sample ports should be based on opaque transfer standards. If the standards are translucent, inter-instrument agreement cannot be achieved. Instrument profiling cannot mitigate the errors that result from the following sample characteristics: (1) Thermochromism. (2) Translucency. (3) Surface inhomogeneity.
The guidelines listed below are based on the sample port sizes of the CE7000A. They are recommended for transfer standards that are used for testing and profiling instruments in the diffuse SCI geometry. The FRL values should be less than 3.5% for instruments that support over-illumination and a LAV, MAV or SAV sample port. For instruments that support a VSAV sample port, the values should not exceed 1.5%.
The author of this article is John W. Root Ph.D. of Mt. Baker Research who can be reached via email at jackroot@mtbakerresearch.com.
Posted by Elaine Becker on Wed, Mar 10, 2010
As the North American Manager of Color Services for Pittsburgh-based PPG, a $16 billion per year manufacturer of paints, coatings, chemicals, optical and glass, Shelley Sturdevant knows something about color matching. She manages and oversees color control for the Coil and Extrusion coatings business at 10 facilities nationwide, with a color palette currently holding over 100,000 colors.
We had the opportunity to spend a few minutes with Shelley as she shared some of what she's learned managing color for PPG over the years:
CyberChrome (CC): What prompted your move into digital color matching and when?
Shelley Sturdevant (SS): About 10 years ago we decided we needed to find the right tools, the right hardware and software, to manage our color needs then and into the future. We needed to build a foundation to manage our huge color palette, including some colors we've been managing for more than 30 years. That's when we settled on OnColor.
CC: What were you looking for in a color matching software application?
SS: Two things primarily, speed and productivity. The OnColor software can search through 50,000 to 60,000 colors in seconds. And, uniquely, it gives you the ability to do very specific color calibrations. It's an important tool for us in the lab but it's also key to our production in batch correction so technicians at all 10 of our facilities can consistently produce the same colors.
CC: Anything else?
SS: Compatibility with a range of spectrophotometers. That enables us to get the best hardware to pair with the software. These tools form the foundation of our house so to speak, but where it really gets interesting and valuable is what you might call the ‘attached garage,' that is, how we use it to interface with our customers.
Now, we're all speaking the same language, not just internally, but we can communicate that directly to our customers. About 40 percent to 50 percent of our customer base has adopted our software and hardware systems models and we train them how best to use it. We can all access the same database which we put up on the Web and they can see new colors, research standard colors, and get precise, reproducible results.
CC: What are some of your newest challenges?
SS: Working to comply with the new ‘green' regulations that have recently been enacted, specifically achieving maximum solar reflectance values (SRVs) without sacrificing the quality of the color match.
These new formulations take the known color matching rules and throw them out the door. The use of brown (blended) pigments to effect L value (versus traditional black pigments) creates new color matching models and obstacles. So, we have to rethink how we match colors.
CC: Thank you for spending time with us.
SS: Thank you.
(Note: Shelley Sturdevant can be reached on email at ssturdevant@ppg.com)
Posted by Mike Burns on Thu, Jul 16, 2009
One of the more frequent questions we hear from suppliers is: What should my color tolerances be? The simple answer equates to what the client will accept in color variation in all directions of color space versus the color standard the supplier needs to match. The importance of the client providing representative color standards will be the subject of a future blog.
In the seventies and throughout the eighties the majority of suppliers relied on the CIELab defaults of +/- 0.5 for *a / *b axis with *L tolerances of +/- 1.0. The CIELab DeltaE default was 1.0. These so-called box tolerances were applied to dark colors, light colors, pastel colors, or high chroma colors with the assumption that regardless of where color was in color space any change in color perceptibility or color acceptability for the color match was the same. The issues with these default numerical tolerances were that the human eye could accept bigger differences in lightness and darkness of darker colors than in lighter colors. The same could be said of the hue (color of the sample). Light pastel colors were more susceptible to a noticeable color difference than darker colors. Consider a light beige where the color shifts a numerical 0.5 towards the -b* axis (bluer). Dependent on the product this shift may be unacceptable whereas in a dark brown or maroon color it may be totally acceptable. There have been shifts of Delta L* (Lightness) of 3.0+ units in a dark royal blue that have been totally acceptable whereas the Delta L* tolerance of 1.0 would indicate it was unacceptable. With these type analogies color scientists sought some way to apply weighting factors to better define color differences dependent on where the color was located in color space.
In the 1980's and 90's, color scientists developed improved color equations like CMC and later CIE2000 for determining a better way to define small color differences that were more perceptually uniform. Both equations use elliptical tolerancing to define an acceptability ellipse for a point in color space. The ellipses vary in shape and size throughout color space. Both CMC and CIE 2000 DE use weighting factors for lightness, chroma (CMC) and lightness, chroma, and hue (CIE2000) that better correlate to color differences asa the human eye sees it. The result over time has been that elliptical tolerances as defined by color difference equations like CMC and CIE2000 are widely preferred within the color industry as being superior in defining human color perceptibility and color acceptability. However, box tolerances are still in widespread use due to their ease of use and the long and extensive color histories that companies have bases on them.
There is no right or wrong answer. It's up to the buyer and seller to negotiate what is acceptable and to clearly spell it out in terms of a color specification.