Correcting the Background

Use the Background Correction command on the Adjust ribbon to make adjustments to the background of your image.  This tool is used to better distinguish image background from image objects, making it easier to extract the objects during a counting or measurement operation.  The Background Correction command can correct uneven background intensities, and compensate for irregularities due to uneven lighting, nonuniform camera response or minor optic imperfections.  It might be used to remove evidence of dust on the lens, or to correct for bright spots caused by the light beneath the microscope's stage.

Two types of background correction are provided by Image-Pro: 

• Background Subtraction should be used for all images except those of transmitted light experiments which will be used to measure optical density. 
• Background Correction should be used for optical density applications, as it accounts for the fact that optical density is not a linear function of the gray scale.

To use the Background Subtraction command, follow these steps:

Open the image that you want to adjust.

Click on Options in the Background Correction group. Indicate whether or not you want Image-Pro to create a separate image from the subtracted background.

Click the Subtract drop-down arrow in the Background Correction group.

You will see the background subtraction options dialog.

Choose a dark or light background to subtract.

The subtracted background will appear in the workspace.

You may also use the browse button to choose a saved image to work with; or create a background image from existing points in the active image.

To use the Background Correction command, follow these steps:

Open the image that you want to correct.

Click on Options in the Background Correction group. Indicate whether or not you want Image-Pro to create a separate image from the subtracted background.

Click the Correct drop-down arrow in the Background Correction group.

You will see the background correction options dialog.

Choose a dark or light background for correction, and indicate the feature width or black level. Your corrected image will appear in the workspace.

You may also use the browse button to choose a saved image to work with; or create a background image from existing points in the active image.