Canon N656U Scan Mode, Shadows, Threshold Value, Tone Curve, Unsharp Mask, White Eyedropper Tool

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Scan Mode

Any one of the various methods used to reproduce image data. Scan modes are distinguished by the number of bits used to describe each pixel. Plug-in Module CS-U features the following scan modes.

•Color (Photos)/Color (Documents): assigns 8 bits of data for each color channel (RGB) in each pixel. Each pixel is therefore assigned 24 bits.

•Grayscale: assigns 8 bits of data to its single color channel. Each pixel is therefore assigned 8 bits.

•Black and White: assigns 1 bit of data to each pixel.

Scanning

The process of using a scanner to read image data. Scanned data is sent to the computer as image data.

Shadows

The darkest portions of an image scanned in a color or grayscale image mode.

Threshold Value

The dividing value at which a pixel is determined to be either black or white when the image is reproduced as a black and white image. The higher the threshold, the darker the image. The lower the threshold, the brighter the image.

Tone Curve

A function used to adjust image brightness. The tone curve (or gamma curve) is a graphic representation of the relationship of the input from the scanner to the output to the monitor or printer.

Unsharp Mask

A function that sharpens image outlines. Makes an image appear naturally sharper without changing the brightness, contrast or color balance.

White Eyedropper Tool

Tool used to the select the brightest portion of an image in the preview area. Used with the Histogram function to adjust image brightness. When this tool is clicked on the image, all areas that are brighter are set to pure white.

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Contents Users Guide When you open the box How to Make Best Use of the ManualsHow to Use this Guide Where to LookAbout the Conventions Used in this Guide Table of Contents Adjusting Scanned Images Operating Environment Installing Plug-in Module CS-UImage Size pp Control Panel FeaturesE P Scanning ProceduresColorSync Ver 2.0 + Compatible for Auto Tone Correction Plug-in Module CS-U Special FeaturesSee the Results of Adjustments Immediately Dynamic Preview Gamma Curve Adjusts Image BrightnessPosition materials for scanning and preview them Install Plug-in Module CS-UQuick Start Instructions Start Plug-in Module CS-USelect the area to be scanned by clicking and dragging Verify Image Quality with the Browser Function beforeSpecify the Area of the Image to be Scanned Click on the Browser button Selection frame will appearSave the Scanned Image p Scan the Image pE P RGB Values Displaying the Plug-in Module CS-U Control PanelOperating Procedures Procedures Positioning OriginalsPlace the original on the scanners document glass Click on the Preview button PreviewingSelecting the Output Device Output Device Resolution= 720 dpi, Magnification= 100% Setting the Resolution and MagnificationSet the desired magnification factor on the control panel To Set the Magnification FactorColor Documents Setting the Scan ModeBlack and White GrayscaleSelect a scan mode from the pop-up menu Click the arrow beside Scan ModeTo Verify the Image Verifying the Image before ScanningUse these buttons to rotate the image Rotating the ImageSetting Preferences Output DeviceAspect Ratio Preview Window UnitReset Default Settings CalibrationClose Plug-in After Scan Operating Procedures Scanning Position the pointer in the preview window Setting the Scan AreaProcedures to Zoom ZoomingSelect the area you want to enlarge with the zoom function Click on the Zoom In button Click on the Scan button ScanningTo Initiate the Scan Specify the Scan AreaEnter a name for the file and click the Save button Saving Scanned ImagesGrayscale, Color Photos and Color Documents Black & WhiteColor Photos and Color Documents Tone Adjustment Dialog Tone AdjustmentHow to Interpret Histograms Histogram SettingsHow to Adjust Histograms To Adjust a HistogramShadow Mark Click on the OK buttonManipulating the Graph Tone Curve SettingsClick the OK button To Edit the Tone CurveValue = Relationship Between the Tone Curve Image BrightnessBrightness and Contrast Settings ContrastBrightness To Adjust the Brightness and Contrast Operating Procedure Adjusting the Color BalanceGamma Value Settings Matching the Gamma Value to the Display CharacteristicsGamma value To Change the Gamma Value Settings To Set the Threshold Value Adjusting the Threshold ValueColorSync Auto Tone CorrectionTo Set the Auto Tone Correction StandardOpen the Image menu and select Unsharp Mask Unsharp MaskOpen the Image menu and select Descreen DescreenSaving/Recalling Settings To Save Settings in a Settings FileClick the Save button To Recall a Settings File Matching Scan Resolution to Purpose Optical and Enhanced ResolutionsScanning Techniques Appendices Troubleshooting Problem Scan button cannot be selected Response Error MessagesError Message CauseBlack Eyedropper Tool GlossaryAuto Tone Correction Bits/Bit NumbersDot Color ChannelHistogram Image FileMagnification Pixel Optical ResolutionResolution MoiréTone Curve Scan ModeShadows Threshold ValueOutput device 7, 11, 18, 25 IndexPage Canon Computer SYSTEMS, INC Canon Customer Support Help DeskOE-040AA 052000 CDS Canon Inc