How to get rid of the 33,3%/50%/66,7% zoom levels and make it smooth?

I'm trying to paint a landscape and the wheel on my Wacom Intuos Pro isn't smooth at all when zooming. It jumps between these increments and I can't stand it.

When I use Alt + Scrollwheel it zooms in much smaller increments. That's exactly what I want on my Wheel on the Wacom, not those gigantic steps. It feels really weird and not very good.

Is there any way to get the wheel to zoom in and out smoothly? You know... like you would expect it to be by default?
Thanks.