Image Tool Controls Area
Auto Redraw—Automatically redraws the image in response to image processing commands. (Default: Selected.)
Brightness—Controls the relative positioning of the centerpoint in the color table that the contrast scale is based on. The brightness value represents a percentage positioning, not a specific color in the color table. When the brightness scale is set on or close to either 0 or 100%, the bottom or top contrast scale colors (respectively) will be truncated. (Default: 50)
Contrast—Controls the contrast of the image as a percentage of the available color table colors or gray tones centered around the color table midpoint. When contrast is at its maximum (100%), the full available range of colors or gray tones is used to display the image. When contrast is at its minimum (0%), only one color or shade of gray is used to display the entire image. (Default: 100)
 
note
Brightness and contrast adjustments work best with a ramped color table. The color table can be ramped using the Color Tool or by selecting Image=>Convert To=>Color=>Linear Grayscale.
You can change the scale value by positioning the pointer in the scale track on either side of the tab and clicking MB1. For each MB1 click, the scale is adjusted by 10% of the maximum scale value from the previous set value.
Magnify ROI—Magnifies a selected region of interest. Brings up the Selected Data Magnified dialog box. Click here for more information about this dialog box.
Magnification—Magnifies an area of the image by one of several power-of-two values. The image area to be magnified is chosen using the Data Selection button on the button bar, and the magnified data is displayed in the Selected Data - Magnified dialog box.
Image Zoom—Scales the original image by multiplying (zooming out) or dividing (zooming in) based on a powers-of-two scale.
 
note
Zoom and Magnification always reference the original image size for every operation. For example, if you first choose a Zoom value of / 2 to get a half size image and then choose x 2, the final image will be twice the size of the original, not the same size as the original.
If you have a very large dataset, we recommend that you use the Magnify Selected Data function rather than Zoom to zoom in on interesting regions. Using Zoom on large datasets can use up server memory and cause unwanted side-effects (the server or the application could crash).
Scale image values—When this option is selected, the image array values are scaled to match the number of colors or gray tones specified by the Minimum value and Maximum value scales. If the button is de-selected, the image values are matched one-for-one with the available colors or gray tones in the color table range.
Minimum value—Select the minimum color range value to use from the current color table. The value can also be specified by double clicking in the text field, typing the value you want, and pressing <Return>.
Maximum value—Select the maximum color range value to use from the current color table. The value can also be specified by double clicking in the text field, typing the value you want, and pressing <Return>.
Lock colormap—If this button is selected and you change the current system color table (e.g., using the ColorEdit Tool), the image’s original colormap is restored every time the pointer focus returns to the Image Tool.
If this button is not selected and you change the current system color table, the new color table remains in effect when the pointer focus moves to the Image Tool.
 
note
You can always restore an image’s original colormap by clicking the Redraw button. Redraw restores the original colormap even if Lock colormap is deselected.