About zoom rgb image and tiff image

[MoonBunnyZZZ]

In the utils/dataset_processing/image.py, class Image has function zoom for zooming rgb image qand tiff image.
Here are something confusing me.I tried factor value equaling 0.5.Two images before and after being zoomed look very different.
Before zoomed

After zoomed

It looks like that the pencil is much closer to the camera in zoomed image.But the distance value of same position of pencil in zoomed tiff image almost equal the original tiff image.I don't know why this data augmentation approach make sense.