Clear glass filters - image degredation or no?

[Sean Dempsey]

I am beginning to wonder if the clear UV filters on all my lenses are a problem or not. Some people say to use them to protect the front glass from damage, some people say they degredate the image too much and only use filters when you need them.

Anyone here done any testing or have any opinions on this? I think I might try shooting without any filters for a week and see if I notice any big changes. This all came up from my Nikon friend having a UV filter on his 500mm, and when he took it off he was surprised and how much the images improved in sharpness and overall quality. I am undecided on this, seeing as how a UV filter saved my lense from getting chipped when I dropped it... the filter got chipped, the lens was fine...

What do YOU think?

[Jeff82]

I have not experienced the image problems that some people ascribe to using filters. However, I have at times experienced problems with flare, and a drop in lens speed associated with using filters.

Other than a circular polarizer and a variety of Cokin filters, the only filter I routinely use is a set of close-up diopters for macro shooting (Hoya HMCs), and I use these often. I honestly can't see any image deterioration caused by the use of these clear close-up diopters.

Having said that I don't use protective filters for general shooting. I"m not sure why, other than that my lens cap it my protection, and that really good Hoya HMC protective filters are expensive.

--Jeff

[another view]

any opinions on this?

There will be a few...

This is a subject that comes up a lot, you might find info in the archives of Viewfinder and Help. Personally, I use them only when I think I'm going to get something on the lens (like in the rain or a windy day by the lakefront, etc). Actually, I can't remember the last time I used one. I never would use one with any other filter (some people always leave them on and put another filter on over the top, like a polarizer, when they use it). They look clear, but what your eye sees and what the camera sees can be a different story. Put it this way - they're not going to help the image. Film used to be more sensitive to UV and they could help on a hazy day, but film has gotten better and I don't think you'll see any benefits with digital either.

I always (well, most of the time) use a lens hood though. Not only does it reduce flare and keep the contrast up, but it provides some physical protection for the lens too. Get the dedicated hood designed specifically for your lens for the most benefit.

[Speed]

I am beginning to wonder if the clear UV filters on all my lenses are a problem or not. Some people say to use them to protect the front glass from damage, some people say they degredate the image too much and only use filters when you need them.

Anyone here done any testing or have any opinions on this? I think I might try shooting without any filters for a week and see if I notice any big changes. This all came up from my Nikon friend having a UV filter on his 500mm, and when he took it off he was surprised and how much the images improved in sharpness and overall quality. I am undecided on this, seeing as how a UV filter saved my lense from getting chipped when I dropped it... the filter got chipped, the lens was fine...

What do YOU think?

Seems to be the question. Like you, I started with UV filters on my lenses. My wife bought them for me when she bought the lenses. And I used them primarily with protection in mind. From what I've read since then, UV filters have limited use for most of us, and are most effective at higher elevations (think Rockies or the Sierras).

While I've never experienced it, I've heard of people getting lens flare, internal reflections, etc, from their UV filters. I also use hoods on my lenses, which has undoubtedly helped. And any glass is going to cut the amount of light getting to the film. It may not be a detectable amount to the eye, but each layer of glass does cut the light transmission.

Today, I normally don't use the UV filters, unless I'm shooting where I'm worried about protecting my lenses from a specific threat (wind, dust, salt spray, etc).