Zoomable image on webpage

[Acorn]

I'm sorry Acorn, I wasn't making myself clear. I know how to do it, WHY am I doing it is the part of the operation I don't understand.

Egg, the why is to magnify the image at present (768) is the width of the presented image so hardly any scaling if the rollover was 512 px wide (x1.5 magnification).
Setting to 1024, 2048, 4096, 8192 are all power of two values so if your rollover image was 512 px wide, you would have magnifications of x2, x4, x8 or x16 times.
Clearly you need a very high resolution image to show off.

Acorn