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FAQQ: What does an ISF Calibration include?1. Evaluate the Viewing EnvironmentAnything short of a completely darkened room will present some degree of a challenge for accurate imaging, and it's important for the calibrator to recognize those issues and minimize them as best he can via the calibration process. For example, uncontrolled ambient lighting in the viewing environment or highly reflective walls, ceiling, and floors will have a direct impact on how you perceive black level. In environments where "critical viewing" is done during both the daytime and in the evening, it may be necessary to calibrate your display separately for these different viewing conditions. 2. Check the Display and All Video Sources for Optimal ConfigurationBefore making any adjustments to your TV, the calibrator should check the configuration of the display and the various video sources it is receiving. The calibrator should ensure that high-bandwidth interconnects (component video, RGB, DVI, or HDMI) are being used for high-bandwidth sources, and that disc players and cable/satellite/teleco receivers are set for the correct screen shape and optimal image resolution. Between untrained cable and satellite installers and consumers who are just overwhelmed by system set-up complexity, it's not uncommon for a calibrator to find multiple system configuration issues during this initial inspection phase. These configuration errors can impose a serious penalty on the viewing experience, if left unaddressed. 3. Optimize Contrast Ratio (Picture Level and Black Level)It's not important to understand the difference between "optimized" and "maximized." Published contrast ratio data for many displays are actually based on maximized settings that would not be tolerable for sustained daily viewing. The calibrator's goal is to discover the optimal combination for black level and peak light output. This means achieving the "blackest" possible black level, without going so low that shadow detail (near-black image areas) is obscured, and then setting peak light output as high as possible, without risking the loss of fine picture detail that can occur if light output is overdone. Excessive light levels can also make it impossible to achieve consistent, accurate grayscale tracking, so this is another factor that will determine optimal contrast ratio. 4. Calibrate Grayscale to the D6500 StandardGrayscale may seem irrelevant when you view a color image in all its chromatic glory, but its importance can be illustrated by lowering your TV's color control to the minimum level. What remains when the color signal is muted is grayscale, an image that contains virtually all of the picture detail in the original color image but with no apparent color. From this exercise, you will see how grayscale is the foundation upon which a full-color image is created. If the display's grayscale foundation is skewed toward blue, or red or green (or some combination of those colors), then the color error in the grayscale image will carry through the color signal is overlaid onto that grayscale foundation. The standard for the color of white has been determined by the Society of Motion Picture and Television Engineers (SMPTE) and that standard is referred to as D6500. All films and television programming produced around the world adhere to the D6500 standard throughout the production process, and your display needs to be calibrated to the same standard in order to produce accurate color images. 5. Correct Color Balance & Re-Align Color DecodingOnce grayscale has been calibrated, the color control should be set for the proper level of saturation of the red, green, and blue primaries, with the tint control used to fine-tune the cyan, magenta, and yellow secondary colors. If the TV's color decoder is correct, then the user-style color and tint controls should be sufficient to produce accurate color balance. However, many displays have "tweaked" color decoders that favor product differentiation over accuracy. In these situations, accessible color decoder controls allow the calibrator to adjust each of the primary and secondary colors independently, and this is the best approach to ensuring correct color reproduction. 6. Reduce Sharpness & Edge EnhancementSharpness, edge enhancement and detail enhancement are "features" that manipulate areas of an image where dark-to-bright transitions exist. Highlighting or "edging" is added to these transitions in order to make the overall picture appear "sharper." And, in fact, these electronic gymnastics may be effective in creating the perception of a sharper picture, but this is accomplished by adding "noise." This noise doesn't exist in the original signal, and its presence actually ends up obscuring picture detail that is present in the signal. Your calibrator should minimize, if not eliminate, all extraneous picture enhancement of this type, particularly in calibrating the display for high-resolution sources that do not normally require sharpening. Other adjustments often included, or provided optionally: maximizing picture viewing area through reduction of overscan; ensuring 1:1 pixel mapping for sources that match the native resolution of the display; eliminating timing errors between the color and black and white components of the signal; adjusting focus; reigning in electronic or optical solutions that dynamically adjust black level or peak light output; and cleaning of lenses or other optics, where present. Also, for CRT-based rear-projection or front-projection installations, calibration will typically include: adjustment of picture geometry; and, convergence of the independent red, green, and blue images. Q: If I decide to get my TV calibrated, how soon after getting it home should I arrange to have that done? Is there a break-in period required?A: Yes, a break-in period is required prior to calibration.There are really two objectives to observing a break-in period. The first is to exercise the phosphors (in a CRT TV or plasma display) or the lamp or backlight (in other types of displays). Both phosphors and lamps tend to be spectrally inconsistent during the first 50 to 75 hours of operation, but after that, both change very, very gradually over a longer period of time. The second reason for a break-in period prior to calibration is to ensure that your new television is a keeper. While televisions today have a very high degree of reliability, problems sometimes occur and studies have shown these are most likely to occur when the TV is either very new or near the end of its rated service life. Therefore the recommended method for "breaking in" a TV prior to calibration is to log at least 75 hours of operation that includes at least half a dozen complete, power on/warm up and power off/cool down cycles. The heating up and cooling down of the television i useful in exposing any components that are going to fail under initial exposure to the extremes of normal operating conditions. Again, there's little reason to expect that your new display is going to suffer a premature failure, but this is one of those situations where a little caution is a good thing. Q: Will calibration void my warranty?A: No, I make no changes that will harm your display.
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Jeff DeBonis - owner
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