# Elastix WeightedCombinationTransform
**URL:** https://discourse.itk.org/t/elastix-weightedcombinationtransform/7568
**Category:** Beginner Questions
**Tags:** registration, python, itk-elastix, elastix
**Created:** [June 22, 2025, 10:08pm UTC](https://discourse.itk.org/t/elastix-weightedcombinationtransform/7568 "2025-06-22T22:08:25Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Sylvester\_Wu](https://discourse.itk.org/u/Sylvester_Wu)
#### Post date: [June 22, 2025, 10:08pm UTC](https://discourse.itk.org/t/elastix-weightedcombinationtransform/7568/1 "2025-06-22T22:08:25Z")
Hi Everyone,
I’m very new to ITK and elastix. I have a set of 2-channel images of Tetraspeck fiducial beads in green and far red fluorescence and would like to register the two channels relative to each other for subsequent correction of chromatic aberration.
Can I average many transformations derived from registering pairs of images? I found these two classes [WeightedCombinationTransform](https://elastix.dev/doxygen/classitk_1_1WeightedCombinationTransform.html) and [WeightedCombinationTransformElastix](https://elastix.dev/doxygen/classelastix_1_1WeightedCombinationTransformElastix.html), but couldn’t figure out how to use them. Could anyone kindly show me some example codes in Python?
Alternatively, is it possible to directly register multiple 2-channel images (i.e. registering a 2-channel stack)?
Thanks!
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [June 23, 2025, 1:26pm UTC](https://discourse.itk.org/t/elastix-weightedcombinationtransform/7568/2 "2025-06-23T13:26:36Z")
Maybe @Niels_Dekker could help? Meanwhile, you could take a look at [registration metric for rgb image](https://discourse.itk.org/t/registration-metric-for-rgb-image/2439).
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### Author:  [@Sylvester\_Wu](https://discourse.itk.org/u/Sylvester_Wu)
#### Post date: [June 23, 2025, 4:14pm UTC](https://discourse.itk.org/t/elastix-weightedcombinationtransform/7568/3 "2025-06-23T16:14:45Z")
Thanks! @dzenanz Let me take a look