Bio-Rad EXQuest Spot Cutter - Manual (Page 102)

Viewing and Editing Images
3-23
Note: If you are using the Transform window in conjunction with the Multi-channel
Viewer, you can adjust the display of each channel independently by selecting the
appropriate channel option button below the preview window.
3.12.a Transform Controls
Auto-scale
Click the Auto-scale button to optimize the selected image automatically. The lightest
part of the image is set to the minimum intensity (white), and the darkest is set to the
maximum intensity (black). This maximizes the display range for the image. You can
then “fine-tune” the display using the sliders.
Select the Always Auto-scale checkbox to automatically auto-scale every image that
you open. This setting disables the remaining controls in the dialog box; the software
will examine the data range in every image and optimize it accordingly.
Auto All will auto-scale all the images in the selected scanset or MatchSet and close
the Transform dialog.
High/Low Sliders
Use the High and Low sliders to optimize the image manually. Drag the High slider
handle to the left to make weak signals appear darker. Drag the Low slider handle to
the right to reduce image background.
As you drag, examine the Frequency Distribution histogram. Everything to the left of
the low slider will be remapped to minimum intensity, while everything to the right of
the high slider will be remapped to maximum intensity. Position the markers at the
ends of the data range in the histogram, and use the low slider to cut off the “spike” of
background noise.
You can also type specific high and low values in the text boxes next to the sliders.
Clicking anywhere on the slider bars will move the sliders incrementally.
If your image data is in a narrow range (as shown in the histogram), select the Log
High/Low Sliders checkbox. This allows for finer adjustments with the slider handles.