CENTER SCREEN AREA / IMAGE CONTAINERS - …
LSM 710 and LSM 780
Carl Zeiss
Raster Scanning Image Correlation Spectroscopy
Systems
250 M60-1-0025
e
02/2010
For a two channel cross-correlation setup, two
drop-down menus will be displayed (Fig. 282). The
upper channel will be the one that will be cross-
correlated against the lower channel. In addition,
two auto-correlations for each channel will be
disputed. All correlations will be displayed in the
Result
table and the correlation image of the
selected row will be presented. Note, if both
channels are identically selected, the cross-
correlation all three correlations will be identical
auto-correlations for the double selected channel.
Remove structures
is needed to remove the
contribution of immobile or slowly moving
structures from the correlation. You can select
what kind of average subtraction you want to
perform from the pull down menu (Fig. 283). If
None
is selected, no subtraction will be done.
If
Slowly moving structures
is the choice the
Average frames
enter box will become available
(Fig. 284). Choose a moving average frame
number that would clean up the correlation from
slow moving structures by entering a number in
the box, by using the arrows or the slider.
Using 5 frames is a good compromise for nearly all
situations. This creates a new stack of n-m+1
frames, where n = number of frames from original
stack and m = number of moving average frames.
Subtraction of the moving average frames from the original frames starts at m/2 and ends at m/2+(n-
m+1) frames of the original stack. Thus the first and last frames of the original stacks are not used. To
avoid negative pixels by this procedure a scalar is added to each subtracted frame that is computed from
all pixels of the moving average that was used for subtraction. The result is a correlation image, that is
not any more afflicted by slow moving and immobile structures and from which fast dynamic processes
can be calculated (Fig. 285).
Fig. 285
Correlation image before (left) and after (right) removal of slow moving structures
Fig. 282
Channels pull down menu for cross-
correlation
Fig. 283
Remove structures pull down menu
Fig. 284
Averaging frames enter box
