Camera Control Dialog — Capture Calibrations

Image-Pro with Capture Module Only

The Calibrations group is a section of the Camera Control dialog. It has a set of controls that can be used to perform background correction and background subtraction on your image.

Dark Frame Subtraction

Using the controls in the Dark Frame Subtraction section, you can improve image quality by subtracting an image which represents the thermal noise characteristics for the camera. The calibration image is created by removing all light from the camera and taking a long exposure. When capturing a normally illuminated image the calibration image will be subtracted to reduce the thermal noise present.

Create: Click to create new Dark Frame Subtraction calibration images. A prompt will appear to indicate that all light should be removed from the camera. Press OK to begin the process or Cancel to exit.

Enable Dark Frame Subtraction: Check this box to apply Dark Frame Subtraction to captured images. It will be disabled if there are no valid calibration files. Click on the Create... button to create the files.

Enable Preview: Check this box to apply Dark Frame Subtraction to the live preview along with captured images. Note that live frame rate may be slower by checking this button. It will be disabled if there are no valid calibration files. Click on the Create... button to create the files.

Exposure Time: Sets the exposure time for the creation of the Dark Frame Subtraction calibration files. The exposure time should be set to roughly the typical long exposure which would be used for the application. The minimum exposure time is 1 second. If the camera does not support at least a 1 second exposure Dark Frame Subtraction is not supported and the controls will be disabled.

Average: Sets the number of files to average for Dark Frame Subtraction. Averaging files will minimize effects due to random noise variations so the calibration image provides a better representation of the noise at every pixel.

Background Correction

Using the controls in the Background Correction section, you can improve image quality by correcting for any uneven illumination caused by the camera sensor or optical path. The calibration image is created by capturing a blank image with the optics being used including any microscopic slide. When capturing a normally illuminated image the calibration image will be divided with the calibration image to correct for uneven illumination.

Create: Click to create new Background Correction calibration images. A prompt will appear to indicate a white area should be shown to the camera. Press OK to begin the process or Cancel to exit.

Enable Background Correction: Check this box to apply Background Correction to captured images. It will be disabled if there are no valid calibration files. Click on the Create... button to create the files.

Enable Preview: Check this box to apply Background Correction to the live preview along with captured images. Note that live frame rate may be slower by checking this button. It will be disabled if there are no valid calibration files. Click on the Create... button to create the files.

Reset:  Click this button to reset all settings to their defaults.