[tmacdon]

I need a 77 mm UV filter for a good new lens (Sigma 70-200 f2.8) fro my K10d.

Should I get a standard one (e.g. $35)? Or would you folks recommend a more expensive multi-coated one (over $100)? I shoot mainly out of doors, and have heard that sun flares on the lens with the cheaper filters.

[Presto]

A good multi-coated filter does help a lot with flare. I think that a good hood helps at least as much as the coating. As for myslef; I always get the coated ones. I'm more inclined to actually use them if I know that they are not going to cause a problem. Another thing is that a lens is only as good as the worst piece of glass in it. That includes the filter.

[tmacdon]

Thanks Presto.. I am taking that advice to the local camera store tomorrow, and will buy the coated filter.

[tibbitts]

I think it depends what you want the filter for, and what brand you buy.

You can choose from non-coated, coated, and multi-coated filters. Multicoating definitely improves performance where there is any potential for flare, and you can find plenty of examples of this. On the other hand, you use the filter (typically) to protect the lens. With a non-coated filter, you can pretty much wipe it off with water and anything handy without significantly damaging it. Even if you do damage it, you can get another one for not much money (I recently got an uncoated 77mm filter for $12), whereas with an expensive multi-coated filter you might be tempted to hang onto a damaged filter. Multicoatings seem to vary pretty dramatically in toughness - some seem to be very fragile.

Paul

[EricT]

This link to a review of UV filters was just posted in another thread:
UV filters test - Lenstip.com

I have a cheap Tiffen UV filter, and it performs pretty badly when shooting into the sun. Otherwise it's fine, though, no noticeable degradation of image quality.

[FengyBoy]

I recommend HOYA HD Digital UV filter which I'm currently using. I used to have couple of HOYA Pro-1 digital filters, they were pretty good as well. But HOYA does claim new HD series can provide better protection and optical quality, compared to the older ones.

[jamesm007]

Stay away from un-coated filters at all costs. The main problem with digital is the reflection off the CCD/CMOS sensor, and there is 100% for sure a reflection of light. Next time your cleaning it look at how shiny it is, especially around the edges. Digital lens use multi-coatings throughout and especially in the back field lens. Hoya PRO 1 D, filters have a special for digital coating, 5 layers total, 3 on the back and two on the front. Why 3 on the back? You guessed it because thats where the most damage from reflections come from on digital cameras, the sensor out! Kenko, Promaster, Hoya, Quantaray made for digital are all the same, and all can be used with the highest of confidence. There are more expensive filters that I have not listed, if your budget allows them, fine. But just stay away from the elcheapo un-coated filters.