Does a UV filter make sense for digital sensors?

[antoine_clappier]

Hi all!

 

I have just ordered an EF-S 17-55 f2.8 for a 40D. I wish to protect it with a

filter without degrading the lens quality.

 

Traditionally peoples buy UV filters for that purpose. But, does it make sense

for a modern digital camera? Is the censor sensitive to UV?

 

If not, what are you using instead?

 

Thanks,

 

Antoine

[jay_lang]

It makes sense. I always put a UV filter on. I'd suggest a top of the range hoya uv as its a nice lens.

[tridakfoto]

Antoine

 

I also have the 17-55mm lens for my 40D and I definitely recommend you getting a UV filter for this lens. Which one you get is up to you but My main purpose for this particular lens is to keep the filter on it to keep the DUST out of the glass!

 

This lens is known for sucking in dust but I put my B+W MRC filter on it as soon as it came out of the box and so far everything is fine. I have tested the lens with and without the filter and you will not see any degradation in your IQ. It is fine and is the best protection for that lens.

 

Highly recommend you do get one and leave it on if possible to keep the dust from getting into the lens and peace of mind also.

 

Have fun with this lens, it is amazing!

 

Jason

[chr15w]

I always use a filter to protect the lens but I now use Hoya pro protector which is coated clear glass

[matt_mcelroy1]

Has anyone ever done tests to see if filters degrade the image quality? You hear people mention this from time to time but since the lens isn't focusing on the surface of the filter does it really ever have any impact?

[frankz]

Gents, I think what he was asking was if he should go with a UV-type cover or a clear glass type as most sensors have a UV panel on them.

 

Your answer would depend on if you like the results without the filter or with or if the a marked UV presence in your photos. If not, just use a good, clear glass 'filter'.

[eric friedemann]

I still use Nikon's L37c coated UV filters, but you could use, for instance, a Nikon NC clear, coated filter instead. I can't see any difference in images as between a coated UV filter and a coated, clear glass filter, but maybe others can:

 

 

http://www.bhphotovideo.com/c/product/121298-REG/Nikon_2482_77mm_Clear_NC_Glass.html

[awindsor]

The amount of UV transmitted through regular lenses is negligible and the Canon filter pack appears to eliminate the remaining UV. You will not see a UV presence in your photos. You can check

 

http://www.naturfotograf.com/index2.html

 

to see how poor the sensitivity of Canon cameras to UV is even with a quartz lens and a UV flash. Under normal circumstance you will not observe any UV effects at all.

 

Having said that I have multicoated UV filters on my outdoor lenses (many of them do a lousy job of filtering UV anyway). My indoor lenses do not have filters on them since in the high contrast lighting of concerts I have seen phantom images resulting from the use of filters. I remove my filters for night photography for similar reasons.

[hjoseph7]

It's amazing how dirty my UV filter gets after a round of shooting. It's amazing that it didn't break yet after banging my lens against church pews, chairs, camera equipment, even walls. However, when I really need to make a shot, I take it off ! and put it back on of course.

[KenPapai]

"Has anyone ever done tests to see if filters degrade the image..."?

 

Well a UV filter will not improve the image (unless you're above 2000 meters?) and I am sure they have a marginally tiny lens image degradation effect -- they must.

 

I don't use filters unless there's an optical reason. Lens hoods are better designed to protect the lens front element (except for the super obvious reasons of swirling sand or salty sea spray).

[bob_osullivan]

While the camera does have UV filtration built in over the sensor, I still use UV filters instead of clear glass. The main reason for me is that I also occasionally shoot film with the smame lenses. So, why not have the option for both. I don't think the additional UV filter degrades the image from what I've seen, aside from Alistair's comments which I would agree with.

[gdanmitchell]

I wouldn't bother with a UV filter. Largely, they are promoted by vendors hoping to make a

bit more margin from the sale.

 

Use your lens hood and a lens cap instead.

[bob_sunley]

Yes adding anything in front of the lens degrades the image. But then the digital sensor does that too, way more than the filter, so install the filter, way cheaper than a new front element. Lens caps don't do much against denting the filter ring when you whack the front of the lens, screw on metal lens hoods are good, but don't protect the glass from dirt and grit. I have an old Nikkormat and a zoom lens that fell nose first 3 feet onto a gravel parking lot, the metal hood had a big dent in it and the gravel gouged the filter. New filter and straightened the hood out and everything is still good 7 years later.

[steve torelli]

This is probably the most asked question in this and every other forum.

The answer to your question about tests with UV filters is yes. Most tests will show a mildly negative affect on IQ but mostly they result in your lens being more prone to flare. There's a page here on Photonet ( I don't remember where to find it ) that demonstrates the increased risk of flare using a UV filter.

 

On the other hand, some people can't sleep at night unless they put a filter on all their lenses. Personally, I agree with Ken Papai and Dan Mitchell and wouldn't think of putting even an expensive filter in front of high quality lens preferring to use a lens hood, which also has performance advantages. Your call, Good luck.

[awindsor]

My UV filters get covered in dust, wind blown sand, and sea spray. The lens hood is designed to protect the lens from stray light not from dust or spray. I can take the filters off and wash them in the sink with dish washing detergent. I could not do that with the front element. There is some image degrading effect but for me the piece of mind more than makes up for it. I always carry an empty 77mm filter box and do take my filters off if shooting near the sun where the extra surfaces of the filter may exacerbate the flare. If you are careful you can see the extra flare caused by the filter in the viewfinder and know that you need to removed it. In teh dark with a single illuminated figure you can get a mirror-like secondary image formed. Since seeing one of those I no longer use filters for situations like this. The same thing is happening in good light except that the secondary image formed is soo dim compared to the the well lit background that it is invisible.

 

Modern lenses with coated and cemented elements transmit very little UV. With some old primes you may find more UV transmission.

[alan_myers]

I'm with Ken, Steve and Dan on this one.

 

Not one of my lenses has a filter installed right now.

 

If/when a filter serves a purpose, I'll install one. Usually, I don't have one installed and I practically always use a lens hood.

 

If you really want to install a "protection filter", that's your choice and done right will pretty seldom have any noticeable impact on your images. You can reduce the negative impact by only using very high quality, multi-coated filters. I think most would point you toward Hoya Pro, B+W and Heliopan filters, as among the best available.

 

Google a bit if you want to see examples of how filters can effect images. I've seen some pages posted out there on the Web, but I don't have any links to offer.

[luminous world]

Whether you need a UV or even a protective filter at all may depend upon the conditions under which you anticipate taking images. I live and mostly shoot outdoors in Colorado. I contend with high altitudes (UV), windblown debris and harsh conditions regularly. I protect all my lenses and replace them often because they become pitted quite fast depsite my regular use of a lens hood.

 

I'd be out of business if I had to replace my lenses every year.

[images_in_light_north_west]

No to filters unless you need an effect like a CPL or ND

[colinsouthern]

Dan Mitchell wrote:

 

"I wouldn't bother with a UV filter. Largely, they are promoted by vendors hoping to make a bit more margin from the sale.

 

Use your lens hood and a lens cap instead."

 

Sorry I'm late everyone!

 

Don't be fooled for a moment - lens hoods protect the lens against stray light - and that's about it - they do nothing to stop sand, dust, dirt, sticky finger, wet noses, ends of tree branches ... and they fall of if you give them any kind of knock (infact my daughter dropped my EF 24-70mm F2.8L USM about 18 inches onto the carpet last weekend - lens hood popped off as usual.) And - heaven forbid - you actually get something like dried salt spray on the lens, just try soaking the lens in warm water (much safer to just soak the filter!)

 

With regards to image quality and using lens caps for protection - my experience is that lens caps degrade image quality HORRIBLY (and of course if you remove them whilst shooting then you lose the benefit of the protection that they provide - so you can't win with them either) (of course, it's a no-brainer to use a lens cap if you're not using the lens! - Doh!)

 

Cheers,

 

Colin

[roger_smith4]

"Has anyone ever done tests to see if filters degrade the image..."?

Sure, it's trivial to do.

 

I ran tests with my Hoya ProMC1 filter (something like that) which is not UV. I mainly want to keep crud off the lens so that when I clean it I don't grind particles into the glass. I did flare tests at night with point light sources, a resolution test looking at crops of a mounted wall map, and found no differences.

[DickArnold]

I don't use filters. I use hoods and lens covers. More importantly I have enough invested in equipment that I have full coverage replacement value insurance on all my equipment and the company has a complete inventory.

[PuppyDigs]

The 17-55 2.8 IS USM is known to have a dust problem due to air vents in the front retaining

ring. By using a filter you seal the front element and greatly reduce dust intake. A lens cover

or hood won't help this problem one iota.

 

Incidentally I never use lens covers. By the time I get it off the shot is often gone...

[antoine_clappier]

Hi all!

 

This forum is truly incredible! Six hours after posting what I thought was a minor question, I get no less than 21 answers!

 

Many thanks for your useful advices. I will add to my arsenal a 77mm filter (I am bit concerned by the "dust problem" that was also noted on others forums).

 

Antoine

[saskphotog]

Colin, do you have any images shot with the lens cap on to show us?

 

I'd like to see just how much the lens cap degrades an image. Does it make a difference whether the lens is wide open or closed down?

 

I have read that lens flare is much improved with a lens cap. Is that your experience?

[tusharrajyaguru]

Here is the opinion of Canon about UV filters:

 

http://www.canon.ca/digitalphotography/english/learn.asp?sid=15

 

For owners of Digital SLR cameras consider:

 

Lens Protection

Consider using a Skylight or UV filter as full-time protection of your lens, shooting your pictures through it and removing it only when you're using another filter for special effect. And of course, don't forget to use your front and rear lens caps!

 

Lens Storage

Your lenses are precision instruments just like your EOS camera is. Protect them from shock, impacts and dust by using an appropriate lens case. And store them in cool, dry areas whenever possible.

 

Canon Lens cleaning kits and lens protection and storage equipment is available at your authorized Canon dealers.