Canon N656U, N1220U, N650U manual Relationship Between the Tone Curve Image Brightness, Value =

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S T E P 3

The Relationship Between the Tone Curve

and Image Brightness

Tone curve values fall with a range of 0.01 to 10.00. A value of 1 appears as a straight line in the graph, and if the value is any value other than one, the line on the graph will appear curved. The relationship between the shape of the curve and image brightness is explained below.

	Value = 1	Output
	Input and output and are equal	Output
	Input and output and are equal
	and the curve appears as a
	straight line, and the input
	image is displayed on the
	screen without adjustment.
	Value > 1	Output
	The data bends upward over	Output
	The data bends upward over
	the range of input values from
	shadows to highlights, making
	the adjusted image brighter in
	the display.
	Value < 1	Output
	The data bends downward over	Output
	The data bends downward over
	the range of input values from
	shadows to highlights, making
	the adjusted image darker in
	the display.

➟

Input

➟

Input

➟

Input

CAUTION

•The tone curve cannot be adjusted manually in one of the color scan modes when ColorSync is selected because the color balance is adjusted automatically.

•The tone curve cannot be adjusted for a black and white image because mid-tones are shown as either black or white. To adjust the brightness of a black and white image, use the threshold setting (p. 48).

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Image 42

Contents Users Guide How to Make Best Use of the Manuals When you open the boxHow to Use this Guide Where to LookAbout the Conventions Used in this Guide Table of Contents Adjusting Scanned Images Installing Plug-in Module CS-U Operating EnvironmentControl Panel Features Image Size ppScanning Procedures E PGamma Curve Adjusts Image Brightness Plug-in Module CS-U Special FeaturesSee the Results of Adjustments Immediately Dynamic Preview ColorSync Ver 2.0 + Compatible for Auto Tone CorrectionStart Plug-in Module CS-U Install Plug-in Module CS-UQuick Start Instructions Position materials for scanning and preview themClick on the Browser button Selection frame will appear Verify Image Quality with the Browser Function beforeSpecify the Area of the Image to be Scanned Select the area to be scanned by clicking and draggingScan the Image p Save the Scanned Image pE P Displaying the Plug-in Module CS-U Control Panel RGB ValuesOperating Procedures Procedures Positioning OriginalsPlace the original on the scanners document glass Previewing Click on the Preview buttonSelecting the Output Device Setting the Resolution and Magnification Output Device Resolution= 720 dpi, Magnification= 100%To Set the Magnification Factor Set the desired magnification factor on the control panelGrayscale Setting the Scan ModeBlack and White Color DocumentsClick the arrow beside Scan Mode Select a scan mode from the pop-up menuVerifying the Image before Scanning To Verify the ImageRotating the Image Use these buttons to rotate the imageSetting Preferences Output DeviceAspect Ratio Unit Preview WindowReset Default Settings CalibrationClose Plug-in After Scan Operating Procedures Scanning Setting the Scan Area Position the pointer in the preview windowProcedures to Zoom ZoomingSelect the area you want to enlarge with the zoom function Click on the Zoom In button Specify the Scan Area ScanningTo Initiate the Scan Click on the Scan buttonSaving Scanned Images Enter a name for the file and click the Save buttonGrayscale, Color Photos and Color Documents Black & WhiteColor Photos and Color Documents Tone Adjustment Tone Adjustment DialogHistogram Settings How to Interpret HistogramsTo Adjust a Histogram How to Adjust HistogramsClick on the OK button Shadow MarkTone Curve Settings Manipulating the GraphTo Edit the Tone Curve Click the OK buttonRelationship Between the Tone Curve Image Brightness Value =Brightness and Contrast Settings ContrastBrightness To Adjust the Brightness and Contrast Adjusting the Color Balance Operating ProcedureGamma Value Settings Matching the Gamma Value to the Display CharacteristicsGamma value To Change the Gamma Value Settings Adjusting the Threshold Value To Set the Threshold ValueStandard Auto Tone CorrectionTo Set the Auto Tone Correction ColorSyncUnsharp Mask Open the Image menu and select Unsharp MaskDescreen Open the Image menu and select 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 Cause Error MessagesError Message ResponseBits/Bit Numbers GlossaryAuto Tone Correction Black Eyedropper ToolColor Channel DotHistogram Image FileMagnification Moiré Optical ResolutionResolution PixelThreshold Value Scan ModeShadows Tone CurveIndex Output device 7, 11, 18, 25Page Canon Customer Support Help Desk Canon Computer SYSTEMS, INCOE-040AA 052000 CDS Canon Inc