Nonrigid will cause the lowest grayscale value of the image to be negative

[Achuan-2]

Describe the issue:

When I set 'nonrigid=True', the minimum grayscale value of the registered TIF image is negative
When I set 'non rigid=False', the grayscale distribution of the image is consistent with the original image

Reproduce the code example:

none

Error message:

none

Version information:

original image histogram

registration tif histogram

Context for the issue:

No response