How do I prevent Solidworks from abruptly zooming out as I am working?

Please view the attached video to best understand the problem that I am experiencing.

When I click Normal to a plane, it zooms wayyyy out.  And other random times, as you will see in the video.

I try clicking F to fit it, but this doesn't really help

Please help.  This becomes especially frustrating again and again and again.

Thanks!

Dan

SolidworksGeneral