Munsell Posters
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A reference for artists, color enthusiasts, and color scientists. Below is a zoomed image of the poster, to which we have added scales, in inch and cm, to show the patch size. Each patch is identified with its Munsell notation. The background is a light grey with a nominal 89% lightness (lightness is the L* of L*a*b*).
Poster available in two editions
Note-1: The number of patches printed on each paper
depends on the gamut that can be achieved by the ink-paper combination. See the
illustration below and the
Poster color accuracy section for additional
information. A comparison of the layouts of the two editions for the Munsell 5G patches:
Poster color accuracyThere is no point in producing a poster about a color system if the colors are not accurate. Defining "accurate" is a tough job though. What is accurate for a person will be rejected by another. Accuracy also depends of the end use; for example, in advertising, company logos and elements of products packaging often have precise colorimetric requirements. Since the accuracy requirements are higher than what can be obtained with blends of the primary printing inks (CMYK), additional inks of the exact color (called spot colors) are used to print these elements. In traditional printing, spot colors require a separate printing plate and it is not difficult to see why the number of spot colors is usually few. Here we have a poster which would ideally require thousands of spot colors! This could be done if we produced each patch individually, at a cost (!), but is definitely impossible when printing all colors simultaneously. So we know from the start that we will need some compromises, but where do we draw the line for accuracy? Let's make a small digression which starts with the raw data. For this poster, the raw data is defined by the "renotated" Munsell data (discussed in the next section), which is XYZ (CIE 1931) color coordinates of Munsell colors as measured with Illuminant C, a now obsolete daylight illuminant relatively close, but not equal, to the more modern D65. The data is first converted to Illuminant D50 in order to be compatible with the ICC Profile Connection Space (PCS) which is now ubiquitous in image processing. In a second operation, an ICC profile is used to convert between the D50 data and the printer colorimetric space. Selecting a perceptual rendering in the second step would maximize the number of colors that can be "perceived" as correct when printed; however, the perceptual rendering shifts ALL colors to maintain a certain relationship, with minimal regards for individual colors' accuracy. Let's not forget that the Munsell Color System can describe all visible colors, a range which is impossible to print, by any means. What is required here is an Absolute rendering, where we strive to reproduce the colors precisely, with the knowledge that this precision will fall dramatically when the colors are out of the printer's color gamut, defined by the range of colors which are possible to reproduce with specific printer's inks laid out on a given paper. Then, in order to improve the gamut, we can "play" with the ink/paper combination. Unfortunately, there is no great freedom in this game. Once you select a printer, this usually fixes the ink choices to sometimes two or three ink-sets, but most often only one, which leaves only the paper selection as the variable. On the plus side, there are more companies offering printers with high-gamut inks than ever before. Still, once a printer is selected, you can only play with the paper to adjust the gamut. Unfortunately, some printers' support software (i.e. drivers) are designed in such a way that it is difficult to use third party papers, even if you generate an ICC profile for them yourself, further limiting a quest for large gamut printing. With the above in mind, we reviewed the market for mid-range professional printers, where mid-range applies here to cost and not print quality, since all the printers reviewed are top-performers in this regard. Our short list was essentially Canon, Epson and HP, and we selected the HP Designjet Z3100 for the following reasons:
Important: This is not a review of the printer, and it is certainly not a global rejection of all other printers, which all have great features! For reviews of the HP Z3100, we suggest: Neil Snape's review; Michael Reichmann's review on The Luminous Landscape as well as his comparison with the Epson 9800; and Uwe Steinmueller's review on Outback Print. You will also find other links to reviews in this unofficial site for HP Z3100 users. At this point, we had data, a method to process it, and some hardware to show it. As can be inferred from the preceding paragraphs, our goal was to maximize the number of printed colors from the Munsell Color System, with a hardware selection which places emphasis on accuracy and stability. Now we can go back to our original question: Where do we draw the line for accuracy? Like many things in life, and particularly for this task, we have to live in a grey zone! We first decided that this poster was not designed for quality control purposes, if only because each color patch is too small to be judged against a test sample. On the other hand, a lot of time was spent making sure the patches would be printed with "accurate" colors. We then decided that we would print only the patches that are considered "in-gamut", as judged with Photoshop "Preview" tool. Because the technical details of this Photoshop feature are not well documented (!), we made numerous print tests where we measured the patches, particularly the ones at the gamut's edge, and compared them to the reference data. We also compared the Photoshop results with other software tools that can predict if a color is within a printer's gamut, and if not, by how much. As well, we visually compared the patches L*a*b* positions in 3D relative to the 3D gamut shape derived from the ICC profile, and the observations matched quite well the Photoshop results. We saw that the Photoshop selection threshold was somewhat flexible; the DeltaE (CIEDE2000) of out-of-gamut color was measured to be between 2 and 7. Please note that these color differences combine the printing error and the measuring instrument's accuracy, and that these colors are "out" of the gamut as flagged by Photoshop, which means that they were not retained for the final product. In short, this is where we drew our line. In practice this means that the absolute color accuracy is slightly less for some colors with maximum Chroma, on the gamut's edge, while being consistently good within the gamut volume. But by how much you may ask? At this moment, we evaluate that the average error is around or lower than 2 DeltaE (CIEDE2000), as measured on a black ISO background. But then comes another parameter, product cost! As we mentioned earlier, the Munsell Color System can describe all visible colors, but no printing system can reproduce such a gamut. This means that all representations of the Munsell system, either in poster form or with large individual patches stored in 3-ring binders, cannot show all Munsell colors. From this fact, taking cost into consideration, we decided to offer two editions of the poster, both using the same printer and inks, but with different paper stocks. The number of patches in the Deluxe Edition, which is printed on a more expensive professional paper which is slightly brighter, is accordingly higher (by 13%), since the gamut edge is pushed to higher Chroma values; of course, both editions are designed with the same approach for accuracy. Munsell Color System infoOriginally developed in the early 20th century by the American artist Albert H. Munsell (1858-1918), this is the first widely accepted color order system. In this system, colors are identified with three parameters: Munsell Hue, Munsell Chroma and Munsell Value, or Munsell HVC for short; they are presented in the form: Hue Value/Chroma. The Munsell Hue is separated in 10 hue ranges (please refer to the illustration below). For each hue range, there is a major hue located at the range center. The major hues are Red, Yellow, Green, Blue and Purple, as well as the five hues located between them and named by combining the names of the hues on each side. For example, the hue located between Yellow and Red is called Yellow-Red, instead or Orange; this naming convention minimizes the number of color names one has to deal with.
Each hue range is further divided in 10 sub-zones defined by
11 radii labeled from zero to 10. The major hues are labeled 5R, 5YR, 5Y, 5GY,
5G, 5BG, 5B, 5PB, 5P, 5RP. The color circle is, in effect, separated in 100 hue
segments where each hue separation is perceptually uniform. A zero to 100 number
can be used to describe the Munsell Hue but it is seldom seen (the zero is at
10RP, the numbers increase when going counter-clockwise, up to 100, also at
10RP). The illustration below presents samples at specific value and chroma intervals for the 5R hue. Only samples that fall within the sRGB gamut are shown; this explains why the maximum chroma is different across the value range. The most saturated sample in the illustration is "5R 5/18". Please note that not all chroma intervals in the illustration represent unitary steps; also, this illustration is not a sample from the posters.
A great tool to learn and practice the Munsell system is The New Munsell Student Color Set, which combines a color-primer book with small color chips; this tool is produced by Jim Long and Joy Turner Luke (Fairchild Books and Visuals (2001), ISBN 1563672006). The Munsell Color System is also supported in other BabelColor products. With BabelColor CT&A you can select amongst thousands of pre-determined Munsell colors in the built-in Color Decks (color databases), and find the equivalent L*a*b*, L*u*v*, and RGB coordinates (for virtually any RGB space). You can also obtain the Munsell equivalent (with fractional accuracy) for any L*a*b*, L*u*v* or RGB input, either manually entered or measured with an Eye-One colorimeter or spectrometer. As for PatchTool, you can obtain Munsell values of any color list, in batch mode, via the PatchTool Export dialog. PackagingThe poster is first rolled and inserted in a plastic bag; the bag is only partially sealed in order to adapt to atmospheric pressure differences. We roll the poster to a diameter which is larger than the original core on which the paper was shipped; this helps minimize paper curl. The wrapped poster is then placed inside a heavy-duty cardboard tube. We make sure that there is free space between the wrapped poster and the cardboard tube; this packaging facilitates poster extraction from the shipping tube and provides extra protection against potential abuse during transit. The Standard edition is shipped in a 3 inch diameter tube while the Deluxe edition, because of its thicker and somewhat stiffer paper, is shipped in a 4 inch tube. Please note that because of its larger shipping tube, the Deluxe edition has slightly higher shipping costs. ShippingWhen the poster is shipped, we send an email with a tracking number and a tracking link (Note: The tracking number may be already included in the email link). For shipments sent via FedEx, the tracking page is here; for shipments sent via Canada Post, the tracking page is here. For Canada Post, the typical "Delivery Standards" (i.e. shipping delays) are described on this page. Please note that shipping delays are expressed as BUSINESS days, that they are valid for MAJOR URBAN CENTERS only, and that additional delays should be expected when there are HOLIDAYS. For example, the Canada Post "Delivery Standard" for an "Expedited Parcel" to the USA is "in as little as 6 days". We have seen shipments arriving within such a delay; however, as you have certainly noticed, there is no maximum written in their standard, and we have also seen shipments arriving in 13 to 17 business days. You should be aware that there is not much we can do once the shipment is in transit, and even Canada Post uses the same information you get from the tracking site, so we cannot provide more information to you during this period. We suggest you select to be informed by email when a "scan event" is registered; this selection is available on the Canada Post tracking page (A tracking number MUST first be entered; then look for the "Request Delivery Updates by email" link). We understand you may be anxious to receive your poster, and we appreciate your eagerness, but we can only ask you for a little patience if this happens. Of course, if the delay becomes worrisome, please contact us. Handling the posterWe recommend using protection gloves designed for photographic applications when handling your poster, which is in fact a high-quality exhibition type print. Such gloves can be found at Gloves-Online and Talas. We particularly like the ones with PVC micro-dots on each finger, from Gloves-Online, which are a blend of cotton and nylon, and which offer an excellent grip as well as a close fit; however, you may prefer a 100% cotton glove, with a loser fit, but more comfortable when weared for long periods. If required, let the shipping tube stabilize at room temperature before opening it; for example, wait for an hour if the tube stayed outside for a while in freezing conditions. Once removed from the tube and from its plastic bag, you should unroll the poster slowly. Even if we roll the posters to diameters which are much larger than what most poster resellers use, some curl may be present once unrolled. The amount of curl will vary with temperature and humidity, and extremes in each should be avoided. Most, if not all of the curl should disappear if you let your poster rest overnight on its own weight, with the printed side on top. However, you may find that, even after a day, the Deluxe version poster is not perfectly flat; still, this will not prevent mounting or framing. If needed, here is a procedure to remove the curliness of the media, which is adapted from a procedure suggested by HP. Important: Be careful when manipulating your poster as you could inadvertently introduce a "kink" in it. You may want to practice with another large piece of paper before doing-it on the poster.
On the other hand, if you intend to have your poster mounted or framed by someone else, we suggest you leave it rolled in its shipping tube. Purchasing info
Click here to read about the differences between the Standard and the Deluxe editions. Click here for some important information on shipping. Save on shipping by ordering more than
one poster. Contact us if you need a quote for specific requirements
Payment processing is done through PayPal; a PayPal account is NOT required. Other questions or problems with the purchasing process?
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