What does the UV len really do?

[Ocelot]

Besides it acts like a lens condom... I shoot pics in the P mode using the 17-85mm len with IS on, the pics are blurry when i had the UV len on (it's really a clear glass IMHO). The pics looked normal when i shoot w/o it... Oh, the pics were taken indoors (i guess you don't really need UV lens covers for indoor, do you?)

If this topic has been discussed earlier, please point me to the right thread, thanks!

[AirBrontosaurus]

Technically it filters out some of the invisible ultraviolet rays that can potentially cause hazy images, but for all intensive purposes, a "lens condom" is about it.

Try cleaning the filter first. If that doesn't work, take it off of your lens, look directly at something in the distance, and them move the filter back and forth in front of your right (or left) eye. If the image distorts, then you have a bad filter. If not, then you're ok.

[Dante King]

http://www.photography-on-the.net/forum/showthread.php?t=209391&highlight=Lens+Filters

http://www.photography-on-the.net/forum/showthread.php?t=213402&highlight=Lens+Filters

http://www.photography-on-the.net/forum/showthread.php?t=212210&highlight=Lens+Filters

http://www.photography-on-the.net/forum/showthread.php?t=210430&highlight=Lens+Filters

http://www.photography-on-the.net/forum/showthread.php?t=189127&highlight=Lens+Filters

This should get you started.

[SkipD]

What a UV "lens" (filter, actually) does is puts money into the pockets of the salesperson who sells it to somebody.

With today's digital cameras, there is so much UV filtering in the lenses themselves as well as the filter over the digital sensors that an extra filter screwed on the lens does almost nothing.

I have never, in over 40 years, found a real need for a "protective" filter. I do not shoot in sandstorms or in salty seawater spray, though. I do use a properly designed lens hood on every lens I use. NONE of my 40-year-old lenses have any damage to the glass whatsoever.

[jr_senator]

...an extra filter screwed on the lens does almost nothing.



Nothing positive, that is, right?

[Curtis N]

It's been a while (at least 6 "UV filter vs. no UV filter" arguments ago) since I posted a link to this thread (http://photography-on-the.net/forum/showthread.php?t=86910). Take a look.

I'm with Skip on this issue. The people who benefit most from UV filters are the people who sell them.

[SkipD]

Nothing positive, that is, right?Well, the two positive aspects of using a very high quality UV filter for "protection" is the fact that it would be less likely to affect the image negatively and, of course, the very high quality UV filters put a greater profit into the pocket of the salesperson.

Most of the time, a high quality UV filter will not noticeably affect an image in a negative way. There are times where even the best UV filter would cause significant degradation that only removing the filter could resolve.

I can certainly think of much better ways to spend my money than on UV filters.

[dylix]

lens condom. haha. do you ever double bag your lens?

[Tee Why]

I like that term of "lens condom" for using UV filters to protect the front element.

[BTBeilke]

Isn't a filter required to the complete the "weather resistance" of some lenses?

[jr_senator]

Isn't a filter required to the complete the "weather resistance" of some lenses?

And the conditions that would bring "weather resistance" into concern are the same conditions that using a "protection" filter would be advised (the lens and camera being a weather resistance type or not).

[Mathiau]

i am glad i got my uv lense, shooting outdoors i have turned around quickly into a branch hanging behind me, right across the front of the UV filter.

better safe then sorry for the $20 it may cost you vs the $800 on a new lense cause it for scratched.

[SkipD]

i am glad i got my uv lense, shooting outdoors i have turned around quickly into a branch hanging behind me, right across the front of the UV filter.Were you using a lens hood?

I have found - through a lot of experience - that a properly designed (rigid) lens hood wards off most impact with things around me. That's assuming, of course, that the lens hood is mounted to the lens whenever the lens is on the camera.

[sandpiper]

I'm with the naked lens people here. I am not about to take a high quality L lens, with some of the best glass money can buy, then stick a piece of lower grade glass in front of it.

I do shoot with filters sometimes, polarizer / ND / Grads etc., but only when the filter is necessary to improve the image. UV filters have no benefit to the image and can cause image degradation. In almost 25 years of shooting I have only damaged two lenses, in both cases a UV wouldn't have saved the lens, it would just be another item to replace.

The money saved in not buying all those filters (one for each lens and it soon adds up), goes to paying for camera insurance which will (mostly) replace the lens if it should get damaged, or pay for a new front element.

Scratching the front of a $2,000 lens doesn't mean throwing the lens away, you CAN just have a new element fitted.

[jr_senator]

Scratching the front of a $2,000 lens doesn't mean throwing the lens away, you CAN just have a new element fitted.

If need be. There is a very good chance that a scratch would not affect IQ at all.

[Mathiau]

Were you using a lens hood?

I have found - through a lot of experience - that a properly designed (rigid) lens hood wards off most impact with things around me. That's assuming, of course, that the lens hood is mounted to the lens whenever the lens is on the camera.

at the time no, i had left it at home :(

[Mathiau]

If need be. There is a very good chance that a scratch would not affect IQ at all.

and still, what would be cheaper, having the element replaced, or a $20 UV filter....

[calicokat]

Besides it acts like a lens condom... I shoot pics in the P mode using the 17-85mm len with IS on, the pics are blurry when i had the UV len on (it's really a clear glass IMHO). The pics looked normal when i shoot w/o it... Oh, the pics were taken indoors (i guess you don't really need UV lens covers for indoor, do you?)

If this topic has been discussed earlier, please point me to the right thread, thanks!

A lens condom, too funny :lol:

[sandpiper]

and still, what would be cheaper, having the element replaced, or a $20 UV filter....

Well, in answer to that question, obviously a $20 filter.

However a cheap filter will cause flare and degradation in the image, so it would have to be a more expensive one. On top of that, having several lenses, it wouldn't be just ONE filter.

If you ask what would be cheaper, a new front element or several $80+ filters, then it would probably be the element (assuming we aren't talking about a long f2.8 lens or similar). Besides, the filters are a definite expense, whereas the 'new element' is only a possible expense, if something goes wrong.

My gear leads a hard life, often in poor conditions and I've gone 25 years without scratching a front element. I have smashed two lenses, but as they were both lying in bits after the incident, a UV filter would have been as much use as a chocolate fireguard.

I'm not saying that those who do use UV filters are wrong, it's a personal decision, just that for me the negative points far outweigh any slight financial considerations.

[jr_senator]

Were you using a lens hood?



at the time no, i had left it at home :(

There lies the problem. I always use a hood except sometimes when shooting macro. My lenses and hoods are stored and carried together. I also have and carry an UV filter to fit my lenses, but, can't recall the last time I felt the need to use one. Thank goodness my few lenses can be covered by just a couple of filter sizes as I have only Heliopan or B+W brands.

[Lester Wareham]

Besides it acts like a lens condom... I shoot pics in the P mode using the 17-85mm len with IS on, the pics are blurry when i had the UV len on (it's really a clear glass IMHO). The pics looked normal when i shoot w/o it... Oh, the pics were taken indoors (i guess you don't really need UV lens covers for indoor, do you?)

If this topic has been discussed earlier, please point me to the right thread, thanks!

I am quite amazed you found such an obvious effect from having a UV filter fitted.

Can you clarify the make and type and if the blurryness was lack of sharpness or flair due to light sources indoors (lamps etc).

[rklepper]

an extra filter screwed on the lens does almost nothing.

I am not sure that is completely true. I know it does nothing for the image and I never use one when shooting indoors. However, I live in Iowa and in the summer time we can get some crazy winds and so I use one when shooting outdoors on a windy day due to the dust storms that can arise at a moments notice. If that is not needed, I would agree that it should be removed.

Also, a cheap filter can destroy a photo and a lens. It can effect autofocus and make everything blurry.

[Jon, The Elder]

Basically it PROTECTS. I shoot horse events and the amount of dirt and crud that gets shot into the lens face is more often than you might think. Yes, I use a lens hood always.

Case in point: rain shower in middle of shoot, no time to clean lens.
Rain stops. Unscrew filter and resume shoot.

Theory and reality often clash.

[jr_senator]

Basically it PROTECTS. I shoot horse events and the amount of dirt and crud that gets shot into the lens face is more often than you might think. Yes, I use a lens hood always.

Case in point: rain shower in middle of shoot, no time to clean lens.
Rain stops. Unscrew filter and resume shoot.

Theory and reality often clash.

If I encounter or reasonably expect your mentioned conditions (or the like), then yes, I would put on an UV filter. But not for my type of usual photography.

[bobgaither]

I seem to get better images with my UV filter, which I use is a B+W, and of course I use a lens hood. I've used cheaper filters a lot of different types in the past but they stay home. I just use that B+W MC UV for all my shots I'd highly recommend that for everyone.

[jr_senator]

I seem to get better images with my UV filter...

I guess I just don't see how use of a UV filter can improve IQ. Protect? yes, but improve IQ???

[CliffordPhotography]

hasnt done anything for me excpet cause clarity problems

[Lester Wareham]

In the true tradition of measurbating:

Filters and AF/Sharpness (http://www.zen20934.zen.co.uk/photography/LensTests/Filter_AF/index.htm)
Filters and Flare etc (http://www.zen20934.zen.co.uk/photography/LensTests/Flare/index.htm)

[Jon]

In the true tradition of measurbating:

Filters and AF/Sharpness (http://www.zen20934.zen.co.uk/photography/LensTests/Filter_AF/index.htm)
Filters and Flare etc (http://www.zen20934.zen.co.uk/photography/LensTests/Flare/index.htm)Nice to see someone who's actually identifying the filters used. Many of the problem reports anecdotally associated with filters either omit mention of the filter make/model or use filters that are widely acknowledged to be lower-quality ones. (no; I didn' actually use the other "Q' word). Also interesting is the hypothesis that lesser-quality coating on the front of the lens may contribute to lens flare linked to the presence of the filter.

[Mike Reynolds]

hmm

[Lester Wareham]

Nice to see someone who's actually identifying the filters used. Many of the problem reports anecdotally associated with filters either omit mention of the filter make/model or use filters that are widely acknowledged to be lower-quality ones. (no; I didn' actually use the other "Q' word). Also interesting is the hypothesis that lesser-quality coating on the front of the lens may contribute to lens flare linked to the presence of the filter.

Thanks Jon.

Just to make totally clear to others, I have had no problem at all with these filters (Hoya HMC), in fact in this test I had to provoke quite hard to get any measurable effect.