"UV" filters.

[Downrigger]

I suppose this has been the subject of fiery conversation here in the past, but I have missed it.

Nothing like data. I read about this experiment with UV filters with interest: http://photographylife.com/lens-filters#more-74143

I would be interested in the opinions of our members.

I put redundant glass in front of my lens because I shoot outside and the dust here in the southwest US is so often quite significant, even on "clear" days, and I am reluctant to be grinding this stuff into my front element with a microfiber cloth. I only take it off indoors, and for sun shots.

[Colin Southern]

Heavens - a couple of the numbers actually went UP slightly with the B+W filters attached. That may put a cat among the pigeons!

Personally, it just confirms to me yet again what I've been saying for years; visually - with the noted exception of extreme contrast scenes - using a quality single UV filter doesn't visually degrade image quality in any way, shape, or form.

Even with a single "bad" filter 99.99% of people couldn't call it correctly in a blind test.

[PaoloMtl]

Thank you for the link, one of the comments on that page directed readers to http://www.lenstip.com/113.1-article...roduction.html and that's where things got interesting for me.

I've wondered why my Nikon 18-105 just doesn't seem as good as my wife's 18-55 or the 35mm lens we have in terms of color rendition and sharpness. While those lenses have Nikon original filters, I went for a deal on Tiffen's "UV Protector" to save some cash. This filter scored abysmally low on the Lenstip tests. The author says it's about equivalent to a pane of window glass ... Seems I have some experimenting to do to make sure before I invest in a better quality filter. Anyone else have a similar experience with Tiffen?

As for the OP... I always put a filter on my lenses. It's a habit I learned from an early age and it gives me much peace of mind when cleaning and roaming into unknown territory. Then again, my friends call me the "boy scout" because I'm often (over)prepared!

[DanK]

I actually tried a blind test some years ago, in response to one of the endless, vitriolic filter-vs.-no filter threads on another site. I put my 50D on a tripod with 60mm macro lens and took two flash photos of a bookshelf, one with no filter and one with a middle-of-the-road Hoya UV filter. I'll post them below. I can't recall which is which. Maybe someone else can figure it out.

I think the bottom lines are pretty straightforward:
--cheap filters are a bad idea
--good filters have minimal effect if the light is behind you
--even good filters can cause ghosting or flare if the light is in front of you.

So I generally leave either plain protective or UV filters on, as I have since 1968. I take them off when there is a reason to, e.g., in doing macro work indoors, where there is obviously no reason to use one, or in doing night photography, where there are often light sources in front of you.

Here are the two images: