Bio-Rad EXQuest Spot Cutter - Manual (Page 146)

Detecting and Editing Spots
4-25
Note: This formula results in more accurate quantitation of imaged spots than summing
the intensities of the pixels in the spot. Measuring the area under the Gaussian
model compensates for peak intensity values that approach image saturation, as
well as background intensity that submerges the intensity of a spot at its edges.
To display the quantities of the spots in a single image, use Show Quantity (Alt+F6,
Spots menu) in the image window. To display the quantities of all the spots in all the
subwindows of a selected window, select Show All Quantity from the Spots menu.
Low Quantity Spots
You can define a set of spots that do not meet a threshold quantity level.
From the Spots > Low Quantity Spots submenu, select Define Low Quan. Set, then
click in the MatchSet or scanset Gaussian image. In the pop-up box, enter a threshold
quantity value. All spots below this threshold will be flagged as low quantity.
When you click OK, a pop-up box will list the number of low quantity spots in the
image and their total quantity. The total number of spots in the image and their total
quantity will also be listed.
Fig. 4-15. Pop-up box displaying low quantity spot information.
The low quantity spots will appear highlighted in the image.
To re-highlight the low quantity spots in the set, select Spots > Low Quantity Spots >
Mark Low Quan. Spots and click in the image.