ColorView III • Use of the Online Shading Correction
14
Altering the lamp voltage
Smaller alterations made to the lamp voltage do not influence the online
shading correction. Larger alterations cannot be balanced by the online
shading correction. Therefore, use the same lamp voltage you utilize in your
normal routine use for acquiring the correction images. Use ND-filters to re-
duce the brightness or acquire new reference images.
Use of the Online Shading Correction
Please note the following instructions for the use of the online shading cor-
rection in order to be able to make optimal acquisitions.
Before acquisition
Before the acquisition procedure, make sure that the optical system is clean.
Check the lamp voltage and check if the Köhler illumination has been set. In
addition, no alterations should have been made to the light path on the mi-
croscope.
Setting magnification
The correct magnification must be set for the use of the online shading cor-
rection. If using macros, do not use the command SetMagnification$(); in the
input channel, as it will be processed too late.
Automatic microscope
It is not necessary to set the magnification when using an automatic micro-
scope which is remote controlled by the application.
Technical Note
Organizing the reference
images
Dark images and correction images are saved to the hard disk. In order to
be able to work with a correct online shading correction when having
changed the camera, the application creates an individual directory for sav-
ing the reference images. This directory is in the application's working direc-
tory. Its name begins with DGSISFW and continues to contain information
about the serial number of the camera being used. This directory should not
be moved or renamed.
The reference images file names are also coded in such a way that the on-
line shading is able to automatically access it. Should one or more of the ref-
erence images have been deleted, the application immediately tells you that
a missing image is required and automatically requires you to reacquire the
missing reference image.
File Format
The reference images are saved as normal TIF images.
Requirements
The filter in front of the camera's CCD chip and all of the microscope's opti-
cal parts must be clean. Otherwise, dust particles or fingerprints would ap-
pear in the correction images. The shading correction can of course correct
such contamination, as long as they remain unchanged. Should a contami-
nant be moved or removed, the shading correction would give you a ghostly
image of the former contamination in each new image. Check the filter be-
fore acquiring the reference images and clean it with a LensPen, if neces-
sary.
intX and Online Shading Correction
The intelligent Exposure acquisition method works problem-free together
with the online shading correction. In some cases, however, the shading
correction can result in over exposure. You will then receive an error mes-
sage when executing a white balance.
Adapting intelligent Ex-
posure
In this case, click the
Options...
button located in the
intelligent Exposure
di-
alog box. Reduce the
Dynamic limit in %
value in the
intelligent Exposure
Options
dialog box to approximately 70.
