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February 19, 2002 of 20

Best Practices for Envision Pro Best Practices .....................................................................................................................................................1 Using Scanners for Image Acquisition................................................................................................................2 What Types of Scanners Can Be Used? ........................................................................................................2 What Types of Samples Can Be Scanned?....................................................................................................3 Recommendations for Using Scanners ..........................................................................................................4 Techniques for Scanning 3-Dimensional Objects ...........................................................................................5

Using Photography for Image Acquisition - Best Practices ................................................................................6 Sample Considerations ...................................................................................................................................6 Photography – General Recommendations....................................................................................................6 Film Photography Recommendations.............................................................................................................7 Digital Photography Recommendations..........................................................................................................8 Photographing Samples in a Veri Vide Light Cabinet.....................................................................................8

Sample Preparation & Backing – Best Practices................................................................................................9 Sample Surround Colors.................................................................................................................................9 Sample Backing - General ..............................................................................................................................9 Mounting Samples on Cards.........................................................................................................................10 Non-Opaque Sample Backing – Scanner Image Acquisition....................................................................10 Non-Opaque Sample Backing – Photographic Image Acquisition...........................................................10 Non-Opaque Sample Backing – Spectrophotometer Measurements .......................................................11

Monitor Calibration............................................................................................................................................12 Monitor Requirements and Specifications: ...................................................................................................12 Monitor Operating Environment: ...................................................................................................................12 Monitor and Software Setup: ........................................................................................................................12 Monitor Calibration: .......................................................................................................................................13 Calibration and Test, Test Results: ...............................................................................................................13 Calibrate Monitor: ..........................................................................................................................................13

Printer Calibration .............................................................................................................................................18

COLORITE Best Practices


Using Scanners for Image Acquisition Images of objects that will be input to Colorite systems are primarily acquired by either photographing or scanning the objects. For more information on the photographic method please see the Colorite document “Using Photography for Image Acquisition – Best Practices”. Using a scanner to acquire Colorite image information has several important advantages over using photographic methods, although this approach is not appropriate for all types of objects. Any flat or nearly flat object can probably be successfully scanned, except those with a glossy or otherwise directionally reflecting surface (such as a textile satin fabric). Objects that have some depth may also be successfully scanned (such as yarns, plastic step chips, and some carpets). Scanning is generally NOT a useful imaging technique for materials which are reflective, metal-plated, holographic, or which have a high degree of gloss. The very high intensity of the illuminating lamp and minimal distance between the lamp and sample creates a high degree of glare which will “wash-out” the image and create areas which will be out-of-gamut in Colorite. With some preparation, three-dimensional objects can be successfully scanned. These techniques involve ensuring the scanner lid has been removed, and scanning performed in a darkened room to eliminate any lighting effects behind the sample. Because of the extremely repeatable illumination and fixed sample distance offered by the scanner, scanning can actually be a superior method of capturing certain effects such as metallic and pearlescent finishes. The primary advantages of using a scanner to acquire Colorite images are as follows: 1. Adequate scanners are currently readily available at prices of less than $150. 2. Scanner image quality is typically good to excellent (for appropriate samples). 3. Sample illumination angle, type, and intensity is fixed and stable 4. Scanner setup and operation is easy, and does not require special skills or additional equipment. 5. Scanner output images are immediately available for review, re-imaging as necessary, possible editing,

and Colorite input.

What Types of Scanners Can Be Used? Because of the rapidly changing nature of product offerings in this technology, testing all the currently available scanners to compare their performance in Colorite applications is not a practical consideration. In general, a low-cost scanner with at least the following characteristics could be considered a good candidate for Colorite applications: 1. Minimum optical scanning resolution of 600 x 1200dpi 2. Color resolution of 36 bits (12 bits each R, G, and B). 3. The ability to scan documents at least 8.5 inches by 11 inches in size. 4. All the software necessary for scanner installation and operation is included. 5. The manufacturer has a good reputation for quality and support services. 6. The scanner is rated by a reliable independent source to have good scan quality. For more information on particular scanners, and for direction as to which ones may currently be rated as “best buys”, it is suggested that independent PC industry web-sites be queried, such as: www.pcworld.com, www.pccomputing.com, and www.computers.com.



What Types of Samples Can Be Scanned? Note that scanner covers (lids) typically include a white material that directly presses against the back of the sample being scanned. If the sample is not backed, the white “show through” may significantly affect the appearance of the sample in the scanned image, particularly when light colors are involved. If the sample itself is light in color or reflective (glossy), the glare produced by scanning may yield an unacceptable scanned image. It is best to use a neutral-colored sample wherever possible. The following table presents information on possible scanner usage and sample-backing recommendations for various types of samples.

Type of Sample Can a Scanner be Used? Textile - fabric - single color, flat (a woven, a knit, or a print substrate)

Yes - If the sample is not opaque, fold it until it appears to be opaque.

Textile - fabric - multi-color pattern, flat (a print, a woven, or a knit)

Yes - If the sample is not opaque, either back it with 1 or more layers of non-colored substrate, or, if a print, fold it once.

Textile - woven or fleece – not flat, but nearly so (blanket material, woven upholstery)

Yes - Fold fleece until it appears to be opaque. If a woven exhibits light show-through, try backing it.

Textile - fabric with a geometrically directional appearance – single color, flat (a satin, or a velour)

Yes – However, the scanner cannot capture the sample’s surface appearance when it is flat, so the material should be loosely “bunched” on the scanner bed, and the lid left open (see “Techniques for scanning 3-dimensional objects”)

Textile - yarn or embroidery floss – presented as a skein or card-wound

Possibly - These samples generally scan well although high-luster yarns usually do not.

1.1.1.1 Textile lace Yes - Can be presented as either a single layer over a black background or in multiple layers (opaque).

1.1.1.2 Carpet Sometimes - If the carpet is tight-looped and does not appear to have much physical depth, scan results may be acceptable. Shag and other carpets with significant physical depth likely will not scan well.

Plastic-coated fabric – flat (an upholstery, or artificial leather)

Yes - If necessary, fold the sample until it appears to be opaque.

Plastics – flat, usually molded, with smooth and/or textured surfaces

Yes – As long as the object is smaller than the size of the scanner bed. However, if the object is glossy and flat, the glare generated by the scanner may yield unacceptable images.

Plastics – step-chips, usually molded, with smooth and/or textured surfaces

Sometimes - Some scanners may not be able to acceptably scan samples with large (deep) steps due to different focal length.

Three-dimensional objects (round, square, irregular) Sometimes – please see “Techniques for dimensional objects”



Recommendations for Using Scanners

The following recommendations concern the use of scanners to acquire images for Colorite applications: NOTE - It is HIGHLY recommended that a professional-quality image editing software package, such as Adobe Photoshop or JASC’s Paint Shop Pro, is installed on the Colorite / scanning system so that images obtained with the scanner can be cropped, resized, and aligned. 1. Scanning Resolution –

1.1. Fabrics – most fabrics will be best represented by scanning at 75 – 150 dpi. This resolution keeps image sizes small yet yields image quality that is more than adequate for most fabrics. Exceptions would be fabrics with extremely high thread counts and minimal texture. In such cases, it may be necessary to increase resolution to 300 – 400 dpi in order to obtain best results.

1.2. Molded/Formed Plastics, uncoated – most plastic objects will require resolution of 75 – 150 dpi. Again, lower resolution will require less memory and will allow smaller file sizes – which can be very important after conversion to LCh image in Colorite.

1.3. Metallic or pearlescent coatings - These require high resolution in order to capture the metallic effect. Use a 400 – 600 dpi setting.

1.4. Wood stains – the scanner is an excellent means of scanning wood grains and wooden objects. 300 dpi resolution should be used.

1.5. Non-effect Paints / Coatings – should be scanned at 300 dpi 2. Color or Black and White? – In most instances, the “True color” or “Best color photograph” setting

should be used for scanning. However, where there are areas of high contrast (large light-dark differences) in the image, or where the target object has significant gloss (such as a satiny fabric), it is often useful to use the “Black and White Photograph” setting. This accomplishes two things: it minimizes some of the glare effects, and keeps the file size small. Where metallic finishes are scanned in this manner, the metalflake effect is well-represented. Obviously, if the target object has multi-colored areas, it will be necessary to scan in a “Color” setting mode; however, monochromatic objects can be scanned in Black and White very successfully.

3. Scan Settings – Scanners include software that usually allow scans to be setup for different brightness

(lightness), contrast, and perhaps highlight or shadow scanning criteria. Unless the operator is experienced with these setup options it is best to scan using the scanner’s default settings. Image editing software packages can be used to modify image parameters in an effort to improve the acceptability of the image, after the image is scanned and saved.

4. Scanner Interface Options – Scanners are designed to connect (interface) with computers using SCSI,

Parallel Port, or USB methods. SCSI models transfer data at the highest rate, while the Parallel Port models transfer at the slowest. Parallel Port and USB models are usually easier to install; however, Windows NT and many Windows 95 users will not be able to connect and operate USB Scanners.

5. Prescans - Most scanners first “prescan” the sample, allowing the user to then select the actual area to

be scanned, thus keeping the image data file to a minimum size. It is recommended that scans be made slightly oversized, with the images later cropped to exact size using an appropriate photo/paint program such as Adobe Photoshop.

6. Moire’ Patterns – if a scanned image exhibits a series of concentric curves that should not be there, the

problem usually involves moire’ patterns. In these cases, it is recommended that the sample be pressed absolutely flat against the scanner’s glass surface, weighting it if necessary, and another scan made. If this doesn’t work, the sample can be scanned again while using the software’s de-screen feature if available. Select the de-screen custom option and set the de-screen dpi value to the number of threads per inch observed for the sample (if a fabric). Note that de-screening may result in an image that is unacceptable because it has lost too much surface definition.



Techniques for Scanning 3-Dimensional Objects Scanning dimensional objects requires a somewhat different approach than scanning flat materials such as fabric or paper. Dimensional objects can be successfully scanned as long as the following guidelines are met: • The areas of the object you wish to image should not be extremely complex, and the area to be imaged

can be stabilized on or secured to the scanner bed

• The object to be scanned must be physically smaller than the scanner bed

• The area(s) of the object you wish to image must be within the focal length of the scanner (approximately 1-2 cm from the scanner bed)

• The object must be able to be held in an orientation that does not cause size/shape distortions when imaged.

• The areas of the object to be scanned should not have shapes/textures which vary in depth/height by more than a few centimeters. This is important to take into account, as large differences in texture or “depth” will create unacceptable shadows and highlights in the image. Examples are shown below.

• The scanner cover should be removed (most scanner covers will detach or simply lift off) or held open in some manner.

• The room in which the scanner is set up should be fully darkened to avoid unwanted background lighting and other image effects. A dark background will make separation of the image in Colorite much simpler, and will enhance the contrast shown on the object in the image.

In order to successfully use the scanner for capturing images of three dimensional objects: 1. Open or remove the scanner cover.

2. Select the view of the object that you wish to image. If the object cannot remain stabilized in this orientation on the scanner bed, you will need to find a means of holding it physically stabilizing the object so that there is no movement during scanning. Using adhesive tape or other material, stabilize the object in the orientation you wish to scan.

3. Again, it is important that the object to be scanned does not have a great deal of deep texture or highly irregular shapes, as these will not be captured well by the scanner.

4. Once the object has been stabilized, darken the room in which the scanner will be used, or at a minimum, use a piece of dark, opaque fabric to block out any overhead lighting.

5. Open the scanner software and begin your scan. Most software will offer a previewing mode in which you can see the result of the scan – this will give you a chance to evaluate the scanning position so that you can make any adjustments required to compensate for glare or shadows.

6. Once a suitable scan has been obtained, save the scan or send it to your photo editing software. You can then resize the image to match the original size (if this is desired) as well as to crop out any unwanted image areas.



Using Photography for Image Acquisition - Best Practices

Images of objects that will be used with Colorite systems are primarily acquired by either photographing or scanning the objects. For more information on the scanning method please see the Colorite document “Using Scanners for Image Acquisition – Best Practices”. When properly executed, the photographic method is not only appropriate for all types of samples, but it also will yield consistently high-quality images. The photographic method, however, is not automatically successful, as the results obtained are very much dependent upon sample illumination conditions and camera settings. Digital cameras offer Colorite users the important advantage that pictures of samples can be displayed on the system monitor soon after a picture has been taken. This advantage facilitates fast and economical retakes should a photograph not be acceptable. However, digital cameras in a reasonable price range ($1,000 - $2,000) capture object information over a limited dynamic range, and this can prove to be too limiting in some sample situations. 35mm cameras offer the likely possibility of consistently obtaining high-quality images, with the additional advantage that good quality 35mm cameras are usually readily available. The main disadvantages of using a 35mm camera are that image data may not be available for viewing for several days after the pictures are taken, and that all images may not be useful.

Sample Considerations Before an object is photographed consideration should be given to: 1. Backing the sample, if required, with additional material, and how to do it. 2. The appearance of the area that will immediately surround the sample in the image. For more information on these important subjects, please see the Colorite document “Sample Preparation and Backing – Best Practices”.

Photography – General Recommendations The following recommendations are applicable for both the film and digital photography methods of acquiring images for Colorite applications:

1. Camera Positioning – in general, aim the camera at the sample at an angle that is perpendicular to the sample surface being photographed. This technique minimizes depth-of-field problems, assures that camera auto-focus systems will work properly, minimizes manual focusing problems, facilitates close-up photography, and simplifies composing the sample in the camera’s field of view.

2. Sample Illumination – in general, the best results are obtained when samples are photographed using illumination conditions similar to those typically employed in a professional photographic studio. In these cases, samples are placed on a copy-board, with the camera positioned so that it is perpendicular to the sample surface. Sample illumination is typically provided by two lamps that are aimed at the sample from opposing angles, each approximately 45

0 to the plane of the sample.

3. Camera Tripod – always use a tripod to hold the camera steady. Colorite exposures are usually made over long time periods that require that the camera remain stationary in order to avoid blurred images.

4. Flash – never use a camera-mounted flash. If the sample is illuminated by such a flash system the illumination will nearly be at the specular angle, and “hot spots” in the image will likely be present.



5. Depth-of-Field – in general, a medium camera aperture (f-stop) setting should be selected.

Higher f-stop settings maximize the camera’s depth-of-focus range of distances to the sample where the image will be in-focus, which offers the best chance that the entire image will be in focus.

6. Macro Capability – in general, use a camera that has a good macro capability (the ability to take pictures when very close to the object being photographed), as Colorite photos are often close-ups.

7. Composing (Framing) the Sample – in general, it is best to position the camera and adjust its zoom control so that the sample nearly fills the camera’s field-of-view. If the sample occupies too small an area of the photograph, it may be difficult to achieve an adequate scanning (digitizing) resolution, particularly when a digital camera is being used.

8. High-Gloss Flexible Samples – in general, if glossy textiles, such as satins, are photographed when they are flat the acquired images will not be acceptable, as the appearance of the directional surface reflections will not be adequately captured. It is recommended that these samples are prepared so that the sample’s surface can be seen at a full range of illumination angles. This can be accomplished by pleating the sample or pulling it through a napkin or similar ring.

9. High Gloss Rigid Flat Samples – in general, the full appearance profile of a flat glossy (plastic or paint) sample cannot be adequately captured in a single photograph. In these cases it is recommended that the sample be photographed using camera positioning and sample illumination as described in the above paragraphs #1 and #2.

Film Photography Recommendations The following recommendations are applicable for film photography only, and should be considered in conjunction with the above General Recommendations: 1. 35mm Format – although larger camera formats such as 2.25” x 2.25” can be used to acquire Colorite

images, the 35mm format offers the advantage that there are many more options available for digitizing the photographs, including Kodak Photo CD.

2. Film Digitizing Methods - Kodak’s Photo CD system offers high quality 35-mm film scans at very reasonable prices. Colorite users consistently report their satisfaction with Photo CD’s quality and low price, generally less than $2 per picture; however, this process takes approximately a week. Many firms other than Kodak offer film-digitizing services with faster turn-around times. Colorite users generally report satisfaction with local film scanning services, although this approach is more expensive than Kodak Photo CD, and image quality may not be as consistently good.

3. Film Scan Resolution – in general, a scan resolution should be selected that results in a displayed image at least as large as desired for the application. The size of the displayed image will depend upon the Colorite system’s selected Display Setting (1280x1024 or 1600x1200 pixels), and the sample size within the photographic image. Photo CD’s two lowest resolutions, which are used for thumbnail images, and the highest resolution (2048 x 3072 pixels), are not suitable for Colorite applications. Either the Base 4 resolution (1024 x 1536 pixels) or the Base 3 resolution (512 x 768 pixels) are recommended, depending upon image size requirements and how much of the original image is to be displayed.

4. Transparency or Negative Film - Although Kodak Photo CD will accept either positive (transparency) or negative film input, Colorite image photographs should be taken using transparency (slide) 35-mm film with an ASA rating of 100 or lower. An important advantage of using slides is that they can be directly viewed using a slide viewer or projector at the full color gamut reproduced by the film.

5. Film Color Balance – the color balance of the film to be used should be selected depending upon the sample illumination being used. Indoor film should be used when using tungsten illumination.



Digital Photography Recommendations The following recommendations are applicable for digital photography only, and should be considered in conjunction with the above General Recommendations: 1. Camera Image Resolution – a minimum resolution of 1600x1200 pixels should prove adequate for

Colorite applications, providing that the sample image fills a sufficiently large part of the total picture area.

2. Camera Color Resolution – the best medium-priced digital cameras offer a maximum color resolution of 24-bits (8 each R, G, and B). At this resolution, the digital camera offers far less dynamic range than that available from 35mm photography. This may result in unacceptable or marginal images when samples contain both important highlight and shadow information. In these cases, the resulting images may sometimes be successfully improved by editing with image/photo editing software.

3. Picture File Size and Camera Memory – in almost all cases, Colorite images should be photographed at the maximum camera resolutions of 1600x1200 pixels and 24-bit (true) color. At these resolution settings, each picture requires an on-board camera memory of about 5.7MB (1600x1200x3). Therefore, at minimum, camera memory should provide storage of 10 or so images at this resolution, as it is not practical to download data every time a picture is taken. File compression formats such as JPEG can reduce the size of files; however, data is lost in the process and this compression format should not be used.

4. Manual White Color Balance – for Colorite applications, a digital camera should have the ability to select the appropriate white balance setting to match the color distribution of the sample’s illumination source. If the camera has the ability to adjust color balance automatically for any light source by calibrating on a white paper or card, that method should be used.

5. Image Quality and Unwanted Camera Noise – a good test of the image quality of a digital camera can be made by photographing a consistent gray sample, then evaluating the image after it is magnified on-screen so that individual pixels can be seen. Under these display conditions, almost all the pixels should appear to be gray (not red, green, and blue mixtures) and not white or black (which would indicate that pixel data has been lost).

For more information on particular digital cameras, and for currently rated “best buys”, it is suggested that independent PC industry web-sites be queried. Some of these are: www.pcworld.com, www.pccomputing.com, and www.computers.com.

Photographing Samples in a Veri Vide Light Cabinet

Photographing samples using the Veri Vide Light Cabinet for sample illumination offers the advantage that an additional sample lighting environment will not be required. Acceptable photographic results have been obtained when samples are placed on the floor of the booth or on an optional 45

0 sample-shelf, although

both methods have some drawbacks. With a sample on the floor of the cabinet the camera should be positioned so that it is aimed at approximately a 45

0 angle to the plane of the sample. With a sample on the

shelf the camera should be positioned so that it is aimed at approximately a 900 angle to the plane of the

sample. When a sample is photographed on the cabinet floor, the resulting image will appear to be somewhat narrower across the top and wider across the bottom (the keystone effect), and it may prove difficult to get the entire sample in-focus. When a sample is photographed on the viewing shelf, the resulting image will likely appear to be somewhat lighter at the top and darker at the bottom. Either of these effects may be objectionable, although they can be reduced by reducing the top-to-bottom dimension of the area photographed before taking the picture or by cropping the resulting image. Images obtained using the shelf method usually have sample surface textures that are more realistic than those obtained with the sample on the floor. For some samples, this may prove to be an important advantage. The shelf method is also easier to implement as the camera can be positioned closer to the sample, image framing is simplified, and camera auto-focus systems can be used reliably. When photographing in the Veri Vide cabinet, the D65 light source should be selected and lamp intensity set at the maximum. If a digital camera is being used the white balance should be calibrated using a white card. If a film camera is being used the film should be color-balanced for Outdoor applications.



Sample Preparation & Backing – Best Practices

Sample images that are displayed in Colorite applications are often compared with actual samples as they are viewed, usually under controlled lighting conditions in a lighting cabinet. Also, these same samples may be measured by one or more spectrophotometers during the product color development process, and/or color specifications may be output to other locations regarding Colorite-displayed colors. Throughout all these activities, consideration must be carefully given as to how these samples are prepared so that the best possible results can be achieved. In particular, sample backing and/or surround conditions should be optimized for the specific situation in order to avoid the very real possibility of introducing significant color display, viewing, and/or measurement errors into the process.

Sample Surround Colors Colors that surround a sample color can have a significant effect on its perceived color. If the evaluated color is in an area that contains other nearby colors and shapes, the adjacent images and colors will affect the viewer’s perception of the target color such as in a print, then the color should be evaluated visually with the printed surround area also in the observer’s field of view. If the colored object or image is essentially a single color, then the object’s surround conditions need to be considered prior to any color and/or appearance evaluation. In general, the best approach when viewing object images in Colorite is to completely eliminate surrounding colors or images, and to use the Colorite-generated gray surround color as appropriate for the lighting cabinet and illuminant/observer combination to be used. In some cases the surround can be eliminated from the object image by simply cropping it out. However, if the object cannot be presented as a perfectly cropped rectangle, then the object’s surround will need to be eliminated from the image during the first step in the Colorite separation process. This is normally the case when a 3-D object is involved, or when a Colorite user chooses to include non-uniform edges of a sample in its image to enhance the realism of the displayed object. In general, object surround colors should be neutral (black, gray, or white) whenever the object will be photographed or scanned, regardless of whether the surround will be included in the final Colorite image. This technique reduces the chance of stray light adversely affecting sample colors during the image acquisition process. If the Colorite separation process will be used to eliminate an object’s surround area from its image, a solid, un-textured surround color should be chosen that is clearly different from any of the main colors in the image so that it can be removed from the image in one separation step.

Sample Backing - General If a sample is fully opaque, it doesn’t matter what is directly behind the sample when it is viewed, measured by a spectrophotometer, or photographed or scanned for Colorite image input purposes. However, if the sample is not opaque, consideration must be given to providing a backing. Failure to choose the correct backing material can adversely affect the results. The sample backing decision should start with consideration of how the sample will be viewed. Once this decision is made the best approach for sample backing during image acquisition (photography and scanning) should be determined. Finally, sample backing during spectrophotometer measurement must be decided. It would obviously be most convenient if the same sample-backing method is used for all these operations, but that may not be the best approach to take.



Mounting Samples on Cards Since samples are often handled many times during the course of using them, it may be a good idea to mount the samples on a card and handle them by handling the card. By using this technique the samples can easily be maintained in an appropriate backing/surround condition. In these cases the card should be solid black, white, or gray. If a white card is to be used, every effort should be made to avoid one that includes an optical brightener (whitener).

Non-Opaque Sample Backing – Viewing Cabinets When a non-opaque sample is evaluated in a Light Cabinet it may be hand-held, placed on the cabinet floor, or placed on a 45

0 shelf. If the sample is not intentionally backed, the gray interior of the cabinet becomes

the backing, and the gray “show through” may influence the appearance of the sample. It maybe useful to consider mounting the sample on a gray card similar in appearance to the cabinet interior. The following table describes and recommends sample-backing methods for these situations.

Type of Sample Recommendation / Comments Textile fabric - single color, flat (print, woven, knit) Fold until the sample appears to be opaque. Try one

fold first and fold again if necessary. Textile fabric - multi-color pattern, flat (print, woven, knit)

Either back with 1 or more layers of the non-colored substrate, or fold once.

Textile fabric with directional appearance – single color: present the sample by pleating or pulling through a napkin ring so that illumination is at varying natural angles

The sample will usually be placed on the cabinet floor or shelf without backing.

Non-Opaque Sample Backing – Scanner Image Acquisition

Scanner covers typically include a black material that directly presses against the back of the sample being scanned. If the sample is not intentionally backed, the black “show through” may significantly affect the appearance of the sample in the scanned image, particularly when light colors are involved. The following table describes and recommends sample-backing methods for this situation.


fold first, and fold again if necessary. Consider mounting on a card.

Textile fabric - multi-color pattern, flat (print, woven, knit)

Either back with 1 or more layers of the non-colored substrate, or fold once. Consider mounting on a card.

Textile fabric with directional appearance – single color (satin, velour, pile)

This type of sample probably cannot be scanned successfully.

Non-Opaque Sample Backing – Photographic Image Acquisition

If a sample is not intentionally backed when being photographed, whatever is behind the sample may influence the appearance of the photographed sample image. If the sample is not intentionally backed, the gray interior of the cabinet becomes the backing, and the gray “show through” may influence the appearance of the sample. It maybe useful to consider mounting the sample on a gray card similar in appearance to the cabinet interior.


fold first, and fold again if necessary. Textile fabric - multi-color pattern, flat (print, woven, Either back with 1 or more layers of the non-colored



Type of Sample Recommendation / Comments knit) substrate, or fold once. Textile fabric with directional appearance – single color (satin, velour, pile)

Present the sample by pleating or pulling through a napkin ring so that illumination is at varying natural angles.

Non-Opaque Sample Backing – Spectrophotometer Measurements

When a Colorite system is being used to determine CIE colors and their associated spectral data, the sample backing and measurement must be consistent throughout the sample preparation and submission process. This way, errors caused by using different measurement techniques will be reduced or eliminated. In many cases, sample backing is by default the white material on the spectrophotometer’s sample holder. The following table describes and recommends sample-backing methods commonly employed in these situations.


fold first, and then fold again if necessary. Textile fabric - multi-color pattern, flat (print, woven, knit)

Either back with 1 or more layers of the non-colored substrate, or fold once.

Textile fabric with directional appearance – single color (satin, velour, pile)

The sample must be measured when flat. Fold until the sample appears to be opaque. Present the sample surface in the same orientation each time.



Monitor Calibration

Monitor Requirements and Specifications: The monitor used should: 1. be a CRT (LCD and other non-CRT designs are not supported). 2. be at least 17 inch in size. 21 inches is recommended. 3. be capable of displaying at a minimum resolution of 1280 x 1024. 4. allow the selection of (white balance) Color Temperature. 5. have a maximum monitor luminance greater than 80 cd/m

2 with the Color Temperature set at 6500K.

6. not have the on-screen Brightness/Contrast display window centrally displayed on the screen (an area reserved by Colorite for placement of the CRT Analyzer probe).

Monitor Operating Environment: 1. The monitor MUST be in a very low ambient light environment 2. No light should be incident on the monitor’s display area. 3. The ambient room temperature should be maintained at a nearly constant level. 4. An operating Spectrophotometer should be located no closer to the monitor than about 1 meter (3 feet). 5. There should be no significant electromagnetic fields present in the vicinity of the monitor, such as those

from large audio speakers, HVAC motors, or power mains.

Monitor and Software Setup: 1. Monitor Color Temperature should be set to the color temperature that is closest to the Illuminant

normally employed for color evaluation purposes (usually 6500K or 5000K). By doing so, the gamut of colors that can be displayed by the monitor is maximized. Select the Color Temperature that is closest to that of the primary CIE Illuminant (or light source) used for color evaluation (design, formulation, quality control) purposes. Select 6500K if using Illuminant C, Illuminant D65, or Illuminant D75. Select 5000K if using Illuminant A (tungsten), TL-84 (Illuminant F11), CWF (Illuminant F2), Illuminant D50, or Illuminant D55. By selecting the monitor Color Temperature that is closest to the source/illuminant that will be used for viewing, the gamut of colors that can be displayed is maximized. 9300K is rarely a good choice. If your monitor doesn’t give you the choice, don’t worry; the monitor calibration will give you the same accuracy whatever your monitor white-point, but you may have a smaller displayable gamut, than a monitor that can be switched to the appropriate color temperature.

2. A display Screensaver should be employed that includes moving images, is not black, and does not

contain any static high chroma and/or highly bright objects. The wait before a Screensaver is employed should be at least 60 minutes so that there is no possible disruption of the Monitor Calibration routine.

3. A display Background should be employed that is not black and does not contain high chroma and/or bright colors. The standard Windows default background is good for this purpose.

4. Windows Display Settings (Select: Start, Settings, Control Panel, Display, Settings) should be set for 24 bit True Color and 1280 x 1024 pixels. The system Graphics Card must be capable of these settings.

5. All Power saving features of the monitor must be disabled at all times; other power saving features of the computer, and/or operating system may be used.



Monitor Calibration: The monitor should normally be calibrated once per day, after the monitor has been turned on for at least one hour. Any “power management” should be disabled so that the monitor is active and the phosphors are allowed to stabilize. Should the ambient temperature significantly change during the day (about + 3

0 C or

more), the monitor should be re-calibrated. The CRT Analyzer should not be located atop the monitor where it can be adversely affected by heat, and objects should not be placed where they cover any ventilation holes which might inhibit heat being dissipated from the Analyzer.

Calibration and Test, Test Results: Monitor Test assesses the accuracy of the monitor’s calibration by displaying and measuring 40 specific colors. These colors have been selected to test the monitor over a full range of Lightness, Chroma, and Hue. Many of the colors are near the limits of the monitor’s display gamut. In some cases, a few of the colors may not be displayable, depending upon the monitor’s gamut. The Test Results report presents the color differences between the CRT Analyzer’s actually measured values for the 40 colors, compared to the desired values for these colors. Any colors that cannot be displayed due to monitor gamut limitations are noted in the report.

Calibrate Monitor: Set: Monitor Color Temperature to the value closest to the Primary Illuminant as described above. The Monitor and CRT Analyzer should have at least 1 hour to warm-up before Monitor Calibration is started. Select menu option: Monitor->Calibrate Monitor (to open the Monitor Calibration window). Select: the CRT Analyzer Model and the COM Port used to communicate with the CRT Analyzer. Select: Test Analyzer if you wish to confirm that Analyzer communications are established through the selected COM Port.

Place the CRT Analyzer probe in the center of this black square (when asked to hold probe against screen).



Select: Calibrate and Test to Calibrate the Monitor and execute a Monitor Test, with the test results automatically saved to file. This is the recommended method for normal Monitor Calibration. Optionally Select: Test Analyzer to perform a communications check between the Monitor and the Computer. Select: Normal Calibration to perform a Monitor Calibration without executing a Monitor Test. Note that Calibrate and Test is the recommended method for normal Monitor Calibration. Select: Test: to perform a Monitor Test without executing a Monitor Calibration. This may prove useful when analyzing Monitor color stability. Check: Check This whenever a new Monitor and/or Graphics Card is connected to the system, or if the Monitor Color Temperature setting (6500K or 5000K) has been changed since the last calibration. The normal calibration procedure requires you to follow the following prompts that will appear at the bottom of your screen.



Reduce Monitor Brightness until the value displayed approaches +(000). Note that the message Close Enough appears when Brightness is less than or equal to +(010), and there is then no need for further adjustment. Reduce Monitor Contrast until the value-displayed approaches +(000). Note that the message Close Enough appears when Contrast is less than or equal to +(010), and there is then no need for further adjustment. It will take several minutes to complete Monitor Calibration and Test, without any need for further operator interaction. During this time the calibration may be left unattended while you attend to other business. Calibration and Test is complete when the above message is displayed. Select: Display Results to display the 4 page Test Monitor report, or Select: Quit to exit Monitor Calibration. Continue to Select Display Results to cycle through the 4 pages of the Test Results report.



The 10 Group 1 colors are all neutral (gray) colors, over a full range of Y values (lightness). The 10 Group 2 colors are all light (pale) shade colors at the same Y value, over a full range of hues. The 10 Group 3 colors are all medium shade colors at the same Y value, over a full range of hues. The 10 Group 4 colors are all dark shade colors at the same Y value, over a full range of hues. The Test Results (CMC 2:1) Overall Average Differences value is an indicator of the quality of a Monitor Calibration. This value should normally be < 1.000. If it isn’t, then the monitor should be re-calibrated. It is useful to observe this figure over several calibrations to get a feeling for what is normal for your monitor (every monitor is slightly different). On most monitors, an average error of much less than 1.0 will be the norm, and a deviation from that norm could indicate an erroneous calibration, even if the deviation is less than 1.0. This could perhaps be due to somebody switching on a light during a calibration, for example. A practical example may be a monitor that usually has an average error of about 0.4, suddenly reporting an average of 0.8 after a particular calibration. In such a case, the user may decide to re-calibrate, even though the average is still less than 1.0. A significant deviation from the normal average is a better indicator of a questionable calibration than an absolute value that is not related to your particular monitor.



The test colors were chosen to be amongst the most difficult to display on an average monitor. It is normal that a few of the colors will fall just outside the displayable gamut of any particular monitor. If a test color cannot be accurately displayed due to gamut limitations the color difference between the desired color and the closest displayable color is computed and the situation flagged. Occasionally, test colors that are normally within the monitor gamut are flagged as out of gamut, or vice-versa. Unless the shift is significant, the occurrence should be noted, but is not necessarily cause for concern. All monitors change their characteristics with age, or if they are moved, knocked, or otherwise adjusted. It is quite normal that some colors will be within the displayable gamut some days, but not others. If the colors return to within the gamut, after a subsequent re-calibrated, it is likely that something unusual may have happened during the calibration (such as a change in room lighting).

Regular observation of the calibration test results will give you a good idea of what is normal for your monitor, and will alert you to any anomalous results that are worthy of investigation. Select: Quit to exit Monitor Calibration.



Printer Calibration Colorite printer calibration must be carefully set up in order to provide accurate and satisfactory results. Because there are many variables that can affect printer calibration, it is important to follow a few basic procedures: 1. ALWAYS set and record the printer driver conditions in Windows Control Panel BEFORE starting

the Colorite printer calibration profile. This is to ensure that the printer driver settings do not change from those set up at the time the profile is generated. Many times printer calibration problems arise because the printer driver settings at the time of printing do not match those set up when the profile was created. In further explanation, please see the illustration below (an Epson 1270 driver Advanced setup):

2. In order to maintain the desired settings during Colorite printing, it is necessary to ensure the

proper paper selection, print quality, and color profiling are set in the driver in Control Panel. If this is not done, the settings may revert to a Default each time that is not equal to the driver properties specified for the Colorite profile. If multiple profiles are used for the same printer, the exact printer properties should be recorded so that they can be reset properly at each printing. Some printer drivers (like Epson) allow the user to define a group of settings and save them as a “setup profile”. If this is available, it is a much simpler way to manage printer properties.

3. It is critically important that the correct paper settings are used, and that they are specified in the

driver properties any time the user changes from one paper type to another. The most frequently used paper should be set as the Default, but when changing from one paper type to another the user must reopen the printer driver and manually set the new paper type. If this is not done, the printed colors will not be accurate.

4. It is important that the proper side of the paper is printed – most high-quality printer papers are

chemically treated on one side of the paper to optimize the print quality. If that side is not consistently used, the resulting colors will be enormously inaccurate.

Disable any color management or color profiling in the printer driver

Ensure the paper specified matches the paper used in the Colorite profile and that the resolution is correctly set



5. It cannot be overemphasized that, for any application of Colorite printing, plain printer paper should NEVER be used. Plain paper is not treated to provide optimum color quality, is very matte, and absorbs ink to a much higher degree than photo quality papers. This results in a dramatically decreased print gamut, which will render saturated colors very muddy and inaccurately. Customers should be advised to purchase photo quality papers which are appropriate for their specific printer.

6. Any color profiling (icc, icm) settings that are used in a printer driver MUST remain constant

during calibration and any subsequent printing. The best practice is to always disable any color profiling (usually found under headers like “ICC Profiling”, “Color Management”, “Color adjustment” or “Color correction”) so that no additional changes are made to the colors sent to the printer.

7. When selecting a profile for printing, always double-check the printer driver properties before

proceeding – this gives the opportunity to ensure that the printer settings are consistent with those originally specified.

8. It is very important to follow the directions in the ImageMaster manual when adding printers and

when setting up new printer profiles. Do not overlook steps in the procedure. Each step of the process must be completed carefully, otherwise improper profiles will result.

9. When updating a pending profile, the incoming *.trm file MUST match the profile number of the

correct profile. If you receive an error message saying the profile numbers don’t match, you are trying to update the wrong profile or are using the wrong *.trm file. Do not attempt to “correct” a mis-matched profile by renaming the *.trm file! This will only create an inaccurate qualified profile and bad color printing. If there is a mismatch, you may import the *.trm file using File>Import as shown on the following page:

Always verify the correct printer settings BEFORE printing!



In the Import Dialog, under files of type select "New printer from TRM file", and locate the desired *.trm files and select "Open".

This will install the profile as a new printer. A dialog box will appear and you'll need to rename the printer – specify the profile properties in a way that clearly identifies them for later use. 10. The illuminant/observer condition on screen must match a qualified profile in order to produce an

accurate print. If these conditions do not match, a warning message will appear in the printing dialog box advising that no qualified profile is available. Additionally, if the following message appears, you will need to verify the print driver set up:

Customers must be advised that Colorite printing is specific to the illuminant and observer conditions used at the time of printing. If the resulting print is viewed under other, ambient conditions, it is likely that the colors will be judged to be inaccurate.

Always check these message boxes – if there is a warning message, the driver setup or the profiles do not match

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