Multi-scale in Object detection?
Multiscale object detection generally consists in smoothing the image with larger and larger kernels, to check  which objects persist across different scales. So, zoom-out, mostly. You now can have access to the scale-space representation of the image, as shown below.



One  reason is that, without more knowledge, one does not zoom in beyond the pixel width. As illustrated (with humour) in the following picture.

 

Meanwhile, in certain conditions, subpixel resolution or superresolution is possible.