Zeiss Lightsheet Z.1, Operating Manual

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CHAPTER 4 - SYSTEM OPERATION
Carl Zeiss Left Tool Area and Hardware Control Tools Lightsheet Z.1
136 000000-1790-528 02/2013
3.3.15.4 Structured Illumination – Fourier
Transform
The Fourier Transform tool computes and
displays the Fourier transform of the image
(frequency space).
Note that the Fourier image will contain the
information on the spatial frequencies, but
does not contain phase information.
Select the Fourier Transform tab to select the
Fourier Transform
Processing tool (Fig. 217).
Activate the image you want to analyze in the
image container and press the
Select button for
Input image to load the image. Then expand the
Method Parameters
tool window to have access
to setting parameters (Fig. 218).
If the
Log FT check box is inactive, the result is the
absolute value of the Fourier transform [sqrt (Real x
Real + Imag x Imag) with Real and Imag being the
real and imaginary part of the Fourier transform]. If
Log FT is ticked, the result is the log-transform of
the shifted absolute values [log (1+ Real x Real +
Imag x Imag)]. Log-transformation squeezes the
dynamic rage of the Fourier-transformed image, so
that weaker intensities may become better visible.
Press
Apply
to compute the Fourier transforms of
all image channels (Fig. 219).
The Fourier images can be used to assess the quality of the SIM calculations and retrieve the
resolution enhancement.
Fig. 217 Structured illumination – Fourier
Transform tool selected
Fig. 218 Structured Illumination – Fourier
Transform tool
Fig. 219 Fourier transform images of SR (left) and WF (right) image
in the Split view