no worries
I wouldn't say it is
the issue its part of the issue. our other points are all important, especially the heat.
i would look into whether it is viable to get a tokina 11-16mm f2.8, in either canon ef mount or Nikon and using an adaptor to the pentax mount. of course you'll lose functionality of auto features, i'm assuming its possible i'm not that familiar with pentax unfortunately?
someone here will probably know.
