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Calibrated fluorescence values are measured in terms of pixel brightness
using Calibrated Units (CU’s).
The fluorescence Min/Max Intensity settings can be adjusted either using the
Auto-Scale function or via Manual Adjustment.
Auto Scale tries to assign optimum Min/Max settings for a particular
image. Auto scaling is easy (just press the “Auto Scale” button), and in
many cases the Auto Scale settings will be adequate. There are times
when the auto scale derived Min/Max settings for one image will not
represent the best settings for other images. If the “Always” box next to
the “Auto-Scale” button is checked, then every time a new image is
selected it will be automatically Auto-Scaled rather than using the values
from the previous image. If a movie is generated, each image within the
movie can be individually auto scaled (refer to section 7.7.2).
To manually adjust the fluorescent intensity values either type new
values directly into the Min/Max intensity boxes and press the “Enter”
key, or use the arrows to scroll through values.
Selecting a Minimum and
Maximum Intensity “clips” the brightness at which fluorescent
components will be displayed. Minimum Intensity: Any portion of the
image with a pixel intensity value less than or equal to the Minimum
Intensity will be assigned a relative brightness equal to the darkest
possible value in the image (in this case black). Maximum Intensity: Any
portion of the image with a pixel intensity greater than or equal to the
Maximum Intensity will be assigned a relative brightness equal to the
brightest possible value for the display (in this case, bright green). All
portions of the image with pixel intensities between the Minimum and
Maximum Intensity values will be assigned intermediate degrees of
brightness
.
Whether Min/Max settings are set manually or via the Autoscale
function, they will remain unchanged until manually re-adjusted or re-
autoscaled on a different image. Therefore, the Min/Max settings
applied to the original image will be applied to all subsequent images
that are viewed within the same vessel at all scan times or even to
images from different vessels. If images are combined to generate
movies, each frame of the movie will contain an image with the same
Min/Max settings.
Tools
The Tool task pane located to the right of the image allows you to zoom in or
out of an image by using the slider bar. Dragging the slider bar will zoom to
the center of the image; however, the area of the zoomed image being
displayed can be changed by grabbing the image and dragging it with the
