[yusuf]

Today I got my new Sigma 10-20mm f4-5.6 EX. It's fantastic. However, one thing I noticed is that the distance between the front element and lens cap is very small and hence a bit worried about possibility of lens cap scratching the element. Anyway, I am buying 77mm filter today itself to avoid any such possibilities however anyone experienced something similar (scratching of front element)?

Also, any suggestions for the filter?

Yusuf

[Ben_Edict]

Today I got my new Sigma 10-20mm f4-5.6 EX. It's fantastic. However, one thing I noticed is that the distance between the front element and lens cap is very small and hence a bit worried about possibility of lens cap scratching the element. Anyway, I am buying 77mm filter today itself to avoid any such possibilities however anyone experienced something similar (scratching of front element)?
Also, any suggestions for the filter?
Yusuf

I've never scratched a lens, because the lens cap had only a small distance to the front element, nor have I heard of such an incident. For the Sigma 10-20, the distance beeds to be that short, to reduce the risk of vignetting and for almost all other extreme wide angle lenses, it is the same. I would not even think about that risk.

To prevent the front lens from scratching you could add a high quality UV filter or protection filter. But even those high quality filters will increase the risk of flareing and ghosting in your lens and in some situation will show a considerable loss of contrast, as has been demonstrated nicely in a recent thread about the issue of protective filters.

Here you'll find more info:
https://www.pentaxforums.com/forums/camera-studio-accessories/95747-protectiv...rs-lenses.html

https://www.pentaxforums.com/forums/pentax-beginners-corner-q/90334-filters.html

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/90875-use-uv-f...lp-needed.html

Ben