UVITEC Cambridge FIREREADER MAX - Page 133

UVITEC – Cambridge
133/225
The centre of gravity of the ball describes a curve:
 This curve represents the noise to be subtracted.
 The curve depends on the size of the ball and on the size of the peaks.
The size of the ball affect the position and movements of the centre of gravity and thus it
determined how much background will be subtracted. A smaller disk will more closely follow
the profile trace, removing more background. A disk radius that is too large will result in poor
background removal. A disk radius that is too small may subtract actual data.
The FireReader 1D calculates automatically the ideal parameter for background subtraction.
This could be manually modified by adjusting the spot size:
To process the rolling ball background subtraction, click on the “Do rolling ball” button:
The changes will be automatically applied to the image.
Note: few seconds could be necessary to perform the background subtraction.
L INEAR APPROACH
The linear approach is a lane-based background subtraction. It allows to manually define the
level of noise to be subtracted on the lane profile. This option gives you the opportunity to set
different background subtraction levels for each lane.
Click on the “Linear ” button:
It opens the lane profile window: