uv filter

[Katy Noelle]

Okay! Say someone, hypothetically, got a bunch of money for Christmas to purchase a Canon 60mm macro prime lens that they've been wanting for a long time. Let's also say, hypothetically, that they've researched the lens and related topics quite extensively and know that's the lens that they want to purchase but cannot, for the life of them, discern which uv filter that they should purchase to protect the new beautiful piece of glass that they have coveted for so long. Let's, also, say that they just can't spend more than $50 on the filter - hypothetically, that is, of course.

In other words, I can't figure out which (52mm), multi-coated, uv filter to get. I know that a digital camera doesn't need the uvfilter but I do want to protect the lens. I, also, understand that it's silly to buy this specially treated lens and, then, stick a silly, untreated filter over it. I've been looking at Hoya filters in the $30 range but some reviews say that they pit and smudge very easily and, when they tried to clean it, the coating came off. (Maybe, they didn't read the instructions that must come with them?) One review, also, talked about the "greenish tint". I don't know if these people even know what they're talking about.

Advice, please.... anyone with experience with these?

[Donald]

Advice, please.... anyone with experience with these?

Hoya 52mm Pro1 Digitial UV - Hypothetically, of course.

If someone was in such a position (to have got this lens), they would have lots of people on a forum such as CiC feeling very jealous. But since we're only talking hypothetically, then there's no need to worry about that!

But if we were not speaking hypothetically, then we'd be saying to this unknown person that they musn't/shouldn't compromise on the quality of the filter. But with a friend like Katy, we know this hypothetical person won't do anything so silly!

[Dave Humphries]

What Donald said

... not that I understood it

but that is the brand and model in their range I always buy

I very recently bought the 58mm size for my latest acquisition

[MiniChris]

Not that I am rolling in dough, but when it comes to a quality lens, it seems silly to compromise on said protection of said lens. $50 is a lot to spend on a small piece of glass, but when one considers the output quality, it comes out to about a 1/10 of a penny a shot over the life of the lens, if even that much.

[carregwen]

Not that I am rolling in dough

I'm rolling in dough... about to take the pizza dough out of the bread maker machine.

I always use a UV filter. I never remove them. I use Hoya Pro.

But then my pizzas are better than my shots...

[Steaphany]

I've noted that some digital cameras actually can detect light in the ultraviolet, < 400 nm, region of the spectrum. This wasn't much of an issue back in the days of film photography because, even though UV filters were available, very few films, unless specifically designed for it, actually sensed ultraviolet light.

Want an example ? Go pull out a fluorescent black light bulb, you know, one of those dark bulbs that visibly emits a dim violet-blue light with strong ultraviolet that make day-glo pigments on posters glow. In a normally lit room, it is important that this is not done in complete darkness, turn the black light on and photograph the bulb with your digital camera.

Does the photo show the bulb at the same relative brightness as everything else in the scene matching how you see the scene with your eyes or is the black light itself glowing brighter ?

If your photo shows the bulb glowing brightly, then that probably means your camera can see into the ultraviolet. If you repeat by adjusting the exposure, banking on spectral sensitivity differences between your camera's imager and it's metering elements, you may get the bulb to photograph with a brightness matching your eyes, but does that also sacrifice the illumination of the other elements in the photo ?

Now try fixing the bright bulb problem with a UV blocking filter. Remember, these are marketed under the guise that the visible spectrum is passed and the ultraviolet, < 400 nm, is blocked. Then photograph the black light again and see if the photo looks any different.

For my camera, a Sigma SD14, I could not cut the brightness of the black light to match my vision until I put on a Hoya $56.85 light yellow K2 filter normally intended for B&W film photography.

Even investing in an expensive, $99.95, nonreturnable special order B+W Type 420 Pale Yellow UV Blocking filter did not yield sufficient attenuation of the black light with my camera.

( This has me thinking I should invest in an ultraviolet passing / visible light blocking filter to try my hand at UV photography. )

Remember, along with protecting that front lens element, the optical properties of a UV blocking filter are supposed to provide for a better image quality than what you are supposed to get without it. Just be aware that the high price may not really be worth much to you in the end.

You'll run into this in the real world when photographing landscapes where you can already see haze. A camera with sensitivity to UV will make the haze look worse since the atmosphere scatters the blue end of the spectrum, which includes ultraviolet, more so that the red. It is situations like this where that UV blocking filter is supposed to do a bit more than protecting your front lens element from dust.

[Geoff F]

On the wildlife forum which I regularly use, some of the 'experts' are once again warning that if you use any type of lens filter you will seriously degrade your photo quality.

My response continues to be that real experts who take much better photos than I will ever manage also use filters and when my almost new canon 24-105 L lens recently fell 3 ft onto a carpeted floor the filter smashed but the lens survived.

So, Katy, my advice would be to fit the filter that Donald advised.

[John C]

I keep a UV filter on my 16-80mm zoom. It was an expensive lens ($750 US) for me and the front element is right up to the front of the lens making it more exposed. I use a B+W 62mm slim UV filter that is multicoated (about $90). Its slim enough not to vignette at 16mm. The coating reduces the chance of having ghost images and reflections fog the lens when a bright light hits the filter at an angle (using a lens cap is a good idea too.) However, its definitely not a case of putting a cheap glass on a good lens.

For my 50mm macro, I don't use a protective filter for two reasons - 1. there is a lot of space - probably an inch from the filter threads to the front element and the front element is a lot smaller diameter than the lens, so its fairly well protected to start with, and 2. I frequently have my ringflash screwed to the lens, so a protective filter is a moot point. You might make sure you really need a protective filter first.

The lenstip website did an evaluation of UV filters a couple years ago. I also think they did an update. Even if you dont look at the results, its work considering the factors that they evaluated.

http://www.lenstip.com/113.1-article...ters_test.html

[Camellia]

Okay! Say someone, hypothetically, got a bunch of money for Christmas to purchase a Canon 60mm macro prime lens that they've been wanting for a long time. Let's also say, hypothetically, that they've researched the lens and related topics quite extensively and know that's the lens that they want to purchase but cannot, for the life of them, discern which uv filter that they should purchase to protect the new beautiful piece of glass that they have coveted for so long. Let's, also, say that they just can't spend more than $50 on the filter - hypothetically, that is, of course.

In other words, I can't figure out which (52mm), multi-coated, uv filter to get. I know that a digital camera doesn't need the uvfilter but I do want to protect the lens. I, also, understand that it's silly to buy this specially treated lens and, then, stick a silly, untreated filter over it. I've been looking at Hoya filters in the $30 range but some reviews say that they pit and smudge very easily and, when they tried to clean it, the coating came off. (Maybe, they didn't read the instructions that must come with them?) One review, also, talked about the "greenish tint". I don't know if these people even know what they're talking about.

Advice, please.... anyone with experience with these?

What are lucky girl!

I use the Hoya Pro1 Digital filter on my 60mm macro. You should be able to shop around to find someone with a good price.

Can't wait to see the results of this hypothetical lens

[Colin Southern]

On the wildlife forum which I regularly use, some of the 'experts' are once again warning that if you use any type of lens filter you will seriously degrade your photo quality.

These are usually the same "experts" who tell us that they use a lens cap for front element protection which - in my experience - degrades image quality considerably more than a UV filter!!

[Dave Humphries]

Hi Steaphany,

I hear what you're saying in general above and it is interesting, but I am concerned it might be interpretted as saying 'it isn't worth buying better quality' - because none of them block UV.

I still believe it is worth not going too cheap though, because all the visible light goes through it too (hopefully) and we want that to happen without distortion, refractions and reflections, the sort of things you'll get with cheap filters.

The filter recommended offers a good balance of price (nowhere near $99) vs optical performance, where yes, it functions principally as a protector. Agreed, it would be nice if it also blocked UV, but personally, I'd see that as a bonus especially as I wasn't aware that my camera is (or may) be that sensitive to UV.

Cheers,

[Steaphany]

John,

Thanks for the link to the lenstip.com article. In reviewing the results, I was surprised at the variation in spectral transmission from filter to filter and this explains the my observations. Including the various B+W filters which pass with little attenuation the black light's 365 nm ultraviolet.

I do find it interesting that the lenstip.com article doesn't mention the B+W 415 or 420 UV Blocking filters. Both are described at being so effective in attenuating UV that both filters have a yellow cast since the attenuation extends into the visible spectrum.

B+W Special Filter Handbook

[Steaphany]

Good points Dave, and as John's post points out, spectral performance can vary greatly even within a single filter manufacturer.

I didn't mean to imply that a UV filter should be omitted or that cost versus spectral performance is the only issue, just as with anything in photography, there can be many factors to consider even for something as simple as a filter. From my perspective, especially with my background in electronic engineering and understanding the spectral sensitivity difference that a silicon imager makes when compared to film, the ability to properly attenuate, when desired, unwanted regions of the spectrum is an important factor to me.

[Katy Noelle]

Thanks, Guys, for your input!!! The hypothetical lens was secretly ordered by my very own guy, yesterday. (He had to 'fess up because I was hellbent on ordering it tomorrow. ) I looked at the filter that Donald suggested and it looks perfect. It costs quite a bit but, through Amazon, it's 60% off, which turns into about $35. (I just put this info in, in case it might help someone else.) It gets the best reviews out of all the ones that I've seen for a very good price.

I just have to say that I love the answers that I get to these techy questions! I read and learn - thanks!

[Klickit]

OK - here's a wee test. I have taken 2 pix with the not-so-L and therefore less hypothetical Nikon 35mm 1.8G lens. One has the UV protector on, one has the UV protector off. No pp whatsoever, apart from a resize and auto sharpen in Irfanview (check the exif) For those who can see a difference, or any degradation, please tell us which is which and specifically what degradation you can see. I'm really interested to know, because I have seen this "Yes you can" "No you can't" argument all over the interwebs so many times and it is driving me quietly bananas. And no, the Engineer has not suddenly grown hair on the top of his head.

.
Number 1.


Number 2.

[Colin Southern]

Well frankly the difference is so obvious it really makes a farce of the whole exercise. Clearly the UV filter is responsible for either inserting or removing the engineer in his entirety!

Seriously though, that aside, they both look "close enough" to me.

There are an aweful lot of people out there that only take photos in a laboratory, and only ever view the results at 100% (on a monitor that's 56 inches wide, and 38 inches high). The one time it CAN make a difference is with high-contrast scenes (eg lights at night) at which point the solution is simple ... just remove the darn thing on that occasion!

[carregwen]

I'd say the second one looks slightly better at 450% magnification. It looks slightly darker, but that could be changes in the cloud cover. Also seems to have a very slight increase in clarity. Much better to ask a more objective question such as "Is Rob's home-made pizza better than anything the Italian's can make?" And the answer is a very definite YES! Or, a more problematic (but still interesting) question, "How many fairies can you get on a pin-head?"

[Klickit]

I'd say the second one looks slightly better at 450% magnification. It looks slightly darker, but that could be changes in the cloud cover. Also seems to have a very slight increase in clarity.

Which, on a two opinion sample, goes to show what I have always thought - that for 99% of the time and for 99% of our images, it doesn't matter a jot so far as the quality of the image goes. Rob's pick that #2 is slightly better and slightly clearer has confirmed that, as #2 is the one with the UV filter.

I did open both these images in PS and take colour samples of single identically placed pixels at 800% zoom and there was a very slight shift in colour, but less, I'll bet, than the naked eye could pick. I think where images do get degraded by filters is because we possibly tend to only clean the filter, when we should really be whipping it off and cleaning the lens front as well. I am definitely guilty as charged.

[carregwen]

Which, on a two opinion sample, goes to show what I have always thought - that for 99% of the time and for 99% of our images, it doesn't matter a jot so far as the quality of the image goes. Rob's pick that #2 is slightly better and slightly clearer has confirmed that, as #2 is the one with the UV filter.

Of course.... I might have been lying to you... it might have been the other way around. And do you know something, I really can't remember now.

Seriously... if I had to step down on one side of the fence to avoid my nuptials being crushed forever, then I I think I'll be going around with a squeaky voice for the next twenty years. There ain't any real difference. But, and it's a big but, I do firmly believe that small (even very small) improvements to a shot setup can make a significant overall improvement to the finished product when seen collectively.

So, if you use an 'L' lens rather than a non-L. put the camera on a tripod at sub 1/100sec, use a recent camera with a better processor, spend a bit more time composing the shot, wait five minutes for the light to improve, get some improved PP skills, etc, etc, you will end up with a better shot. Each on their own may not make any significant, or even identifiable difference to a shot, but together they can.

[inkista]

Coming in a bit late, but after reading this lenstip comparison of UV filters, I just get the Hoya HMCs.