Hi, I need some expert advice, I have a Canon 7D and the 50mm f/1.2L, 24-105mm f/4L and the 50mm f/2.5 Macro, I want to buy UV filters mainly to protect the front Lens, one option is to buy the Canon UV HAZE filters and the other one I like is the Sigma DG UV Multi Coating filters, any previous experience with those UV filters ?, any recommendation which one is better ?, thanks

one option is to buy the Canon UV HAZE filters and the other one I like is the Sigma DG UV Multi Coating filters, any previous experience with those UV filters ?, any recommendation which one is better ?, thanks

The Canon filters are generally poor compared to the best multicoated filters. I don't personally have exerience with Sigma filters, but a brief internet search seems to indicate they are good. Hoya HMC and B+W multicoated are often recommended.

I'm using both Hoya and B+W multicoated UV filters on my 7D (and EX3 - also 77mm = easy to swap stuff around if needed). I have no complaints. I generally buy 'slim' versions of any filter, where available for 2 reasons;

1. as these reduce the risk of vignetting if ever fitted to wide angles, e.g. on my Canon 10-22mm (who knows you might buy a wide in the future)
2. in the case of the EX3, allow the filter to fit and the Sony hood to be reattached.

In all cases, I generally leave them on the lenses for the important protection reasons, only taking them off to fit an alternative filter such as a circular polariser (again B+W, slim).

Some people like to have NO filters at all, for risk of extra fare/distortion. Personally, I don't want the risk of scratching my expensive lenses and have n't noticed any real problems on that front anyway - just buy good quality multicoated filters and you're all set.

Also, see this relevant and current thread for more comments.

http://www.dvinfo.net/forum/canon-eos-7d-hd/471727-canon-protect-filter-ef-50mm-f-1-2l-usm-lens.html