User`s manual

Chapter 5: Analysis Tools
5-65
Auto Spot Options
Bright Spot vs Dark Spot
The Bright Spots selection should be checked if the image contains bright spots on a
dark background (eg ethidium bromide stained fluorescent gels and chemiluminescent
blots). The Dark Spots selection should be made when the sample contains dark sample
on a light background (film, commassie blue protein gels etc..). The software should
automatically determine this selection, but the user may have to override it if the
software incorrectly evaluates an image. Remember as in all portions of AlphaEaseFC
software if the image has been reversed (negative image)using the Reverse selection on
the Contrast Adjustment window the Dark Spot selection should not be made. Reverse is
a visual alteration only and does not effect the original image capture data. (EG if a
chemiluminescent blot is captured using the Reverse mode in order for it to appear as
film, the correct selection is still Bright Spots).
Find Spots
The Find Spot button is selected once the correct area of interest is drawn and the Bright
Spot/Dark Spot selection is correctly made. A green outline will be drawn around the
detected spots.
Background Threshold
The background threshold slide bar will adjust the criteria used for finding spots. It is on
a scale of 0 to 100% saturation. The sliding bar maps the dynamic range of the camera.
By calculating the fringe pixels in the image or ROI, the initial threshold value and
suggested lower (or upper) bound value are calculated and shown on the sliding bar. The
user can always override the threshold value by moving the sliding bar or typing in the
counter box.