Sigma LBA-400 Manuel D’Utilisation

 

•  If the Set Reference Source item is set to Current Frame, the data in the currently 

viewed frame will be copied to the Reference frame. 

•  If the Set Reference Source is set to Last Gauss, and the Gauss Fit item in the 

Computations... dialog box is checked, then the beam profile resulting from a 

computed Gaussian fit to the currently viewed frame will be copied to the Reference 

frame.  

•  If the Set Reference Source is set to Auto Gauss, and the Gauss Fit item in the 

Computations dialog box is checked, then the beam profile resulting from a computed 
Gaussian fit to newly acquired frames will be automatically copied to the Reference 

frame.  In this mode, setting a reference frame manually does not make any sense 

because the next frame brought into view will automatically update the contents of the 

reference frame. 

 
Note:  In the last two examples, if the Gauss Fit item is not Checked, then no fit is computed and thus no data will 
be copied to the Reference frame. 
 

3.2.4.10 Convolution 

The term Convolution indicates a type of two-dimensional spatial filtering that can be applied to 

a digitized image.  We will not attempt to use this term in any restricted construct.  Rather we 
will apply it generally to a variety of area process transformations.  At the time of this release we 

are providing just a few convolution algorithms, these primarily aimed at simple low-pass spatial 

filtering.  We expect this list to grow in time, and welcome suggestions from our users for 

additional implementations. 
Click on this edit control to see a list of Convolution algorithms.  Entries in this list that begin 

LPF #, indicate a Low-Pass filter.  This is the most commonly used algorithm for simple image 
smoothing operations.  The numbers following define the size of the convolution kernel in pixels.  

For example, 3x3 indicates a 9 pixel kernel 3 pixels by 3 pixels.  Other common sizes are 5x5 and 

7x7. 
We recommend that you experiment with these selections until you find a process that meets 

your specific needs. 
See Convolution in Section 6.27 for more details regarding how these algorithms are applied. 

 

You can select which functions you want to appear on the Capture Toolbar by checking the desired 

item.  The functions will appear on the toolbar in the same order that they are listed in this dialog 
box.  The first four panels; Capture, Camera, Trigger, and Processing, are analogous to the items 

listed in the Capture dialog box.  
 The panel labeled Other offers you the following two tools that are associated with File menu items, 

and a third item that is not available anywhere else. 

 

Operator’s Manual 

 

LBA-PC 

 

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