Zoom in and out with two different step sizes?

[Elk]

Is there a way to zoom in and out in the full size view for an image by using the mouse scroll wheel in combination with pressing a key in two different step sizes? E.g to zoom in / out quickly (e.g with the mouse wheel) and slowly (e.g with the mouse wheel and pressing CTRL).

[xnview]

sorry but no way

[Elk]

Ah, that's a pitty. Many thanks!