Depending on the part characteristics and the feature being viewed, the right combination of lighting may aid in bringing out a particular feature. Take time to experiment by balancing the available light sources. 8.4 Magnification and Focus Strategy Accurate measurement requires proper focus of the image. With a zoom lens, focusing is most sen- sitive at highest magnification. A good strategy is to first focus the image at the highest magnification, and then decrease magnification to the desired level. In general, high magnification (or zoom) helps with accurate measurements. However, while high magnification provides high resolution, it does not always provide the highest accuracy, and not all features should be inspected at the highest available magnification. Too high a magnification may make it difficult to discern the edge of a feature by exaggerating edge defects such as burrs and chips. Try decreasing the magnification until the edge is more clearly definable. Also, there is an inverse relationship between magnification and field of view, and using a lower magnification may be more convenient. Also consider factors such as tolerance requirements, functional requirements, manufacturing pro- cesses, and optical characteristics of the part. Features with loose tolerances may not need to be inspected at high magnification. Experiment to select the magnification that is most suitable for the feature being inspected or measured. 8.5 Parts Fixturing and Skew Control The part must be fixtured securely to prevent part movement during measurements. Also, the feature being measured must be aligned with the measurement axis or with the X-Y stage if stage’s X-Y encoders are used to make measurements. If the part is off angle, a condition known as skew will introduce measurement errors. Aligning the part with the measurement axis or with the X-Y stage will result in more accurate measurements. With M3 software, skew errors can be removed by creating a reference frame based on the part before taking measurements. Please see the M3 software manual for details. 8.6 MetLogix D1 and M3 Software Operation KineMic systems with Shuttle PC come with either MetLogix M3 or MetLogix D1 software, as ordered. M3 software is full-featured 2D metrology software with video edge detection (VED) and lighting control. By using VED, features and geometries to be measured can be selected by using the mouse or simply by tapping the touch screen. Measurements can be within the field of view or be automatically integrated with encoder readings from an X-Y stage (KMR-200-M3 system). D1 software offers many of the same real time image display, markup, and archiving capabilities as M3 software, as well as basic geometrical constructs like points, lines, circles, distances, and angles. However, edges are selected manually using crosshairs on the screen, not automatically via VED, and lighting control is via knobs, not software. D1 software is suitable for measurements within the field of view and for measurement using crosshairs and a micrometer stage (KMR-50- D1 system). M1 or M3 software operation is outside the scope of this hardware-oriented user manual. Please refer to the separate MetLogix D1 or M3 software manual.
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