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Resampling Properties
Use this page to configure the way images are
re-sampled. This page also selects which transformation is being
used to achieve registration.
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Image Registration Resampling
Properties
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Transformation
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Specifies the mathematical mapping between the
marker coordinates in the reference image and the target
images.
Shift: Corrects a
coordinate displacement in the x and y directions.
Shear: Corrects
coordinate displacements, rotation, non-perpendicular axes, and
unequal scale in the x and y directions.
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Resampling method
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Specifies the method used to compute image
intensity at fractional pixel coordinates.
Bi-linear: Computes
a linear interpolation between pixels in the x and y
directions.
Bi-cubic: Computes a
4 term cubic polynomial interpolation between pixels in the x and y
directions.
Nearest Neighbor:
Uses the pixel nearest to the transformed coordinate instead of
re-sampling the pixel values. This inflates the FWHM by about 0.3
pixels but preserves the noise structure of the image, which can
have important consequences when
aperture photometry or
image cleaning will be done on the registered
images.
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Reference Image
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Select the reference image onto which the
transformation mapping is computed. This image is not
resampled.
NOTE: Choose the Reference Image on the
Resampling Properties page before
computing the transformation using the  button
on the
Image Registration toolbar.
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Residuals
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Opens the
Image Registration Residuals window where you
can view or analyze the residuals of the fit to the transformation
equations. The residuals show the distance, in pixels, between the
marker points and their predicted positions in the registered
images. This can be used to spot bad points that can give a bad
transformation solution and should be deleted before the
transformation is recalculated without them.
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 Conserve Flux
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Check this box to conserve flux (sigma per unit
time) in the transformation equations. For example, if conserving
flux and the output pixel is 1/2 as wide and 1/2 as tall, then the
signal is 1/4 as high.
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Save Undo Copy
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Check this box to save an Undo copy of each image
before registration is done. This allows you to recover the
original images if you want to re-do the registration. Uncheck this
box to save memory, which can be a critical issue when registering
many, large images that may need all the memory available on the
computer.
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Verbose
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Check this option to give verbose listing of
registration results.
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Recommendations
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Use the Shift
transformation when there is no significant rotation or scale
difference between the images.
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Use the Shear
transformation then there are scale differences and/or rotational
differences between the images.
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Use the Bi-cubic
resampling option when images have sharp features and many point
sources.
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Use the Bi-linear
option if the bi-cubic filter leaves ringing artifacts. The
bi-linear kernel is less sensitive to sharp points but applies more
smoothing to the image. For most images, you should choose the
Bi-cubic filter.
Related Topics
Registration Properties Dialog
Image Registration
Background Properties
Mira Pro x64 User's Guide, Copyright Ⓒ 2023 Mirametrics, Inc. All
Rights Reserved.
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on the Image Registration toolbar and
select the 