How to Properly Use iamwarp.

I am attempting to write a code that corrects for the unwanted curvature of a slit of light. The code will be used to correct for future data acquisitions, though for now I am having a hard time finding out how to use the iamwarp function. I simply want to know how to properly input what is needed for the function to work.

From the doc: "imwarp(A,tform) transforms image A according to the geometric transformation tform. The input image A can be a numeric, logical, or categorical array. tform is a geometric transform object"

I'd like to know how to input 'tform'. Our data is in .fits files.

[Walter Roberson]

https://www.mathworks.com/help/images/ref/affine2d.html or https://www.mathworks.com/help/images/ref/projective2d.html or https://www.mathworks.com/help/images/ref/affine3d.html