[BigMackCam]

Whenever I read negative statements on the use of UV filters to protect lenses, I feel compelled to defend my use of them; not because I think I'm right, but because there *is* no right or wrong in the matter; it's my choice, based on what matters to me personally.

The main criticism of filters is that they degrade IQ, and I agree there's that possibility - particularly with respect to flare and ghosting with strong light sources, where there can be no argument. However, my personal preference is to work around that by removing my filters only when such conditions might arise. Some forum members may also recall that I found a number of UV filters that introduced banding and adversely affected the rendering of bokeh. Since then, I've switched to Hoya HMC UV(0) filters and I find the IQ to be very, very good. Yes, there are a few rare occasions where I might notice tiny differences in 1:1 zoomed images, but this is at a pixel-peeping level.

I've attached four pairs of 1:1 crops taken earlier today with a K5 + M50 F1.7 at F8, ISO 160, unenhanced except for default sharpening in LR6. In each pair, one was taken with the UV filter, and one without. I've mixed up which sides they're on. Oh, and to replicate my typical outdoor abuse of my UV filters, I breathed on it and wiped it clean with my shirt tail first

In each pair, can you tell which one is with the filter (left or right) and which is without - and WHY?

Pair 1 - Fence post
Pair 2 - Planter barrel
Pair 3 - Door mat
Pair 4 - Brick wall

If you *can* tell which is which and why, do you consider the differences to be significant for the purposes of viewing at, say 1:3 or even 1:2, or printed?

In fact, in one of the pairs I *can* see a difference, where the "without filter" image has slightly better IQ. It could be tripod movement, or maybe it really was caused by the filter. Even so, I personally feel it's insignificant at most viewing and printing sizes.

My closing advice to anyone who'll listen is that you should use, or not use, UV filters based on your assessment of what matters to you and whether you are happy with the results - and not on other's opinions stated as fact. Of course, that's just *my* opinion!

Attached Images

       

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Last edited by BigMackCam; 08-26-2015 at 06:54 AM.

[jatrax]

I feel compelled to defend my use of them;

Why?

I don't feel compelled to defend my not using them.

[BigMackCam]

Why?

I don't feel compelled to defend my not using them.

We're just different, I guess

[Na Horuk]

Well, use them if you want. Like you said, once you scale the photo down to e-mail or facebook size, once you make postcard sized prints, the differences in resolution will be gone. Flaring, ghosting, or blemishes on the filter are the main problems, but a good, deep lens hood would fix most of those.
That said, I'd rather use just a hood than a filter, just because a filter might cause loss of IQ, whereas a hood will not (unless its too tight and causes vignetting or too cheap and causes reflections). I would only use protective filters in harsh conditions. To shield it from wind-driven desert sand or salt-water spray or industrial leftover dust.

Hm, btw, I noticed many brands are now selling "protection filters". Are these any different from UV filters? More durable, maybe?

[spoiler]Oh, and are the filter photos on the left side? Those seem softer, except for the last one, but it sometimes looks like it might be shake blur[/spoiler]

[BrianR]

Along with the help of my trusty flipping coin, I'll guess the ones without the filter are on the Left, Right, Right, Left.

Unless you're printing pretty huge and viewing from uncomfortably close (or your filter is an utter piece of garbage), I don't think you'll see much difference under conditions like these.

Edit- the obligatory link to the LensRentals UV filter stack test http://www.lensrentals.com/blog/2011/06/good-times-with-bad-filters

[UncleVanya]

Right, Right, Right, Right are my guesses for where the filter was used. Slightly softer image to my eyes but my vision isn't great so it could be fatigue. The first one seems to have lowered contrast on the right hand picture also. Honestly each time I look most of the shots are hard to judge. The last two seem easier to see a difference than the first two.

I'm a no UV guy myself.

[ppppsssstttt]

those are pretty dark scenes. i thought that one of the reasons not to use a UV filter is because you can introduce flare with the extra glass.

[BigMackCam]

... I'd rather use just a hood than a filter, just because a filter might cause loss of IQ, whereas a hood will not (unless its too tight and causes vignetting or too cheap and causes reflections). I would only use protective filters in harsh conditions. To shield it from wind-driven desert sand or salt-water spray or industrial leftover dust.

Entirely reasonable. And with vignetting, you can easily remedy that in post-processing. So, yes, I think hoods are a great idea. Except for the built-in one on my Jupiter 21M which seems to have zero effect whatsoever!

Here in the North East of England, we get our fair share of poor weather, and when I visit the coast, the salt-water deposits on my filters are very noticeable, along with a few grains of sand if I head onto the beach...

Hm, btw, I noticed many brands are now selling "protection filters". Are these any different from UV filters? More durable, maybe?

I'm not sure. My guess was that they were simply clear, anti-reflective coated glass with no spectral filtering - which, actually, would be fine for me

[spoiler]Oh, and are the filter photos on the left side? Those seem softer, except for the last one, but it sometimes looks like it might be shake blur[/spoiler]

I'll wait to see if there are any more players first, and let you know later

---------- Post added 08-26-2015 at 04:13 PM ----------

those are pretty dark scenes. i thought that one of the reasons not to use a UV filter is because you can introduce flare with the extra glass.

Yes, they are - and I agree. When I feel there's a risk of flare or ghosting, I remove the filter. I've been caught out on a couple of occasions, but generally that approach works for me...

[othar]

Along with the help of my trusty flipping coin, I'll guess the ones without the filter are on the Left, Right, Right, Left.

+1
Not much of a difference but I believe the same

[romay]

It really depends on the situation. None of your pictures are taken in a situation where an additional glass surface would matter.

There is always a sloss in sharpness when you add a planar glass surface to an otherwise perfect optical system, but the filter thickness is usually so small in relation to its diameter that this becomes purely academic.

The flare issue is currently the most critical one when using filters.
Telephoto lenses are not so critical, as the filter's coating works best when incident light is perpendicular.
A wide angle lens and the sun in your frame - not so good. Combine that with a filter with low quality coatings and it can make your picture unusable.
It becomes most noticeable if you do HDR photography, as the tonal compression tends to pull up the ghost images.

However, lots of landscape photography is done using resin filters - more often than not, they are even stacked and none of them are coated in any way.
Still people achieve great results with that, so I would say it's really a matter of experience and personal preference.

I for one always use high quality UV filters with my tele lenses simply because I never had anny issues and they are much easier to clean.
For my wide angle lenses, I usually do some testing with and without filter. The flare issue varies from lens to lens as it depends a lot on the bulge and coatings of the front element.
If I find my lens unaffected, I keep the filter on.

[BigMackCam]

The flare issue is currently the most critical one when using filters.
...
A wide angle lens and the sun in your frame - not so good.
...
However, lots of landscape photography is done using resin filters - more often than not, they are even stacked and none of them are coated in any way.
Still people achieve great results with that, so I would say it's really a matter of experience and personal preference.
...
For my wide angle lenses, I usually do some testing with and without filter. The flare issue varies from lens to lens as it depends a lot on the bulge and coatings of the front element.

Thanks, that's very interesting. The only wide angle lenses I own are the DA15, DA21 and DA20-40, all with the HD coating and hoods (well, I have some infrequently-used manual 28's too, but they're mostly just to play with). Of those, I've only run into a tiny bit of trouble with flare on the DA15 (which makes sense from what you've said), and I simply removed the filter during the time I was shooting.

I've never even heard of resin filters! I'll have to do some reading

[pathdoc]

UV filters are supposed to be useful with film, not so useful with digital. Given that many of my lenses (albeit not all, because some are APS-C only) could easily find themselves on a film camera at short notice, I see no problem with reaping the benefits in these terms as well as in terms of ballistic or spray protection. So they make sense for me from both angles. For a lens which never leaves the studio, whose camera never leaves a very sturdy tripod, I can well understand the motivation not to use one.

[BigMackCam]

For a lens which never leaves the studio, whose camera never leaves a very sturdy tripod, I can well understand the motivation not to use one.

Indeed. I'd be much less biased towards using filters if I was limiting my lenses to indoor use only...

[Quicksand]

UV filters are supposed to be useful with film, not so useful with digital. Given that many of my lenses (albeit not all, because some are APS-C only) could easily find themselves on a film camera at short notice, I see no problem with reaping the benefits in these terms as well as in terms of ballistic or spray protection. So they make sense for me from both angles. For a lens which never leaves the studio, whose camera never leaves a very sturdy tripod, I can well understand the motivation not to use one.

FWIW I look at it from an almost diametrically opposite angle.

As long as I don't know what lighting conditions I'll be shooting in -- toward the sun, or with bright specular reflections, or in dim conditions with bright lights in-frame -- I'd rather NOT introduce that extra glass. Under controlled conditions it might matter less.

I do use hoods religiously, though, and as far as I can tell modern coatings are very scratch resistant. I have never scratched or damaged a lens (well, not the glass parts at least!) in eight years of shooting with a DSLR.

Sure, there's a significant element of luck to that. But if I ever do damage something I hope I'll take it reasonably in stride, given that I have knowingly assumed some risk.

[BigMackCam]

FWIW I look at it from an almost diametrically opposite angle.

As long as I don't know what lighting conditions I'll be shooting in -- toward the sun, or with bright specular reflections, or in dim conditions with bright lights in-frame -- I'd rather NOT introduce that extra glass. Under controlled conditions it might matter less.

I do use hoods religiously, though, and as far as I can tell modern coatings are very scratch resistant. I have never scratched or damaged a lens (well, not the glass parts at least!) in eight years of shooting with a DSLR.

Sure, there's a significant element of luck to that. But if I ever do damage something I hope I'll take it reasonably in stride, given that I have knowingly assumed some risk.

Again, entirely reasonable, and it's obviously working well for you

I once went on a guided trip with a professional photographer in Uppsala, Sweden. He didn't use filters, but he abused his lens and there were scratches and marks galore. Interestingly, none of his images seemed to suffer I'd love to be so carefree with my gear!