Change of opinion re: UV filters

<p>Whether to use UV filters on lenses as "protection" or not seems to be a recurring point of discussion on this and other forums.</p>

<p>Personally, till now I've held the opinion that having a UV filter on can't do much harm – after all, it's easily removed in situations where it may contribute to flare or ghosting. Today however, I mounted up the trusty 70-200 (for the first time in a couple of weeks) and headed out to take some wife/dog portraits at the beach. Removing the lens cap I heard a crunching sound, which turned out to be the shattered pieces of the Hoya HMC pro UV filter that lives on the front of this lens. After carefully removing the filter ring and gingerly brushing the shards out of the front of the lens, I see that I now have a small (approx 1mm) scratch on the front element of my previously pristine zoom.</p>

<p>OK, I'm VERY careful with my camera gear, and am at a complete loss as to when this might have occurred. It definitely wasn't shattered when I last put the lens cap back on the lens. The lens itself has only been in a padded case and my drybox, and the cap itself is undamaged. Regardless... it happened somehow, and I'm less than pleased at the damage to the lens, however minor.</p>

<p>I note that with the design of the Nikon pinch-type lens caps, quite a large area of the inside of the cap sits in very close proximity to the surface of any flat, screw-in filter – perfectly positioned to transmit the force of any shock to the cap, directly to the delicate glass of the filter itself. This is not the case (at least on any of the lenses I own) with a bare lens, due to the varying degrees of indentation of the front elements.</p>

<p>And so, my opinion of UV filters has changed. I now consider them more potentially HARMFUL to my lenses than PROTECTIVE, and thus won't be using them in future.</p>

<p>Thanks for reading my little rant :-)</p>

<p>Chris</p>

<p>So isn't the culprit the lens cap not the filter?</p>

<p>I'm surprised that your filter was hard enough to scratch your lens surface. Maybe the scratch only goes as deep as the coating. This kind of damage probably won't affect your pictures.</p>

<p>Maybe there's something to be said for only using a cheap plastic UV filter?</p>

<p>I despair. Anecdotes of this type are like the arguments about whether it's safer to have a seatbelt on or to be thrown from the car. Stories of individual occurrences share (like the kid who put his whipped iced milk on the front of my expensive zoom lens, the dad wanting me to buy the kid a new ice cream cone!*) in the lack of controls on what happened and so prove almost nothing.</p>

<p>There are two ways this could be settled. One is to collect as much information about endurance of lenses with and without "protection". This would have to be a large sample and truly random in selection of information. Statistical analysis could then see if there were any <em><strong>statistically significant</strong> </em> differences between filter users and non-filter users in terms of lens damage. What makes it tough is that there are hundreds of different filters and different lenses, so there would have to be a huge sample, probably, to eliminate such "noise" in the data.</p>

<p>The other way, would be to take 3 or 4 different kinds of filters, put them all on some particular decently built lens, and drop kick the lenses with and without filters into the next state or wherever. In short an actual experiment with controlled variables, standardized elements, and double-blind rating of results. While expensive, this would be much easier to make a case one way or the other with.</p>

<p>I think neither the lens makers or the filter makers want to know this so much that they would fund such studies. Both would be expensive, and the makers are happy with the current state of ignorance. If they have any results of this kind, they sure aren't sharing it with us. Are they ignorant or apathetic? I suspect they don't know <em>and</em> they don't care.</p>

<p>_____<br /> *yes, I had a UV filter on, thank goodness.</p>

<p>If something DID impact the filter, but did not damage the lens cap, what happens if there is no filter in the path and the mystery impact happens again ? Wouldn't it hit the front element instead of the filter causing a lot more damage ?</p>

<p>Since you don't know how the damage occured how do you know that had it not been for the filter the front element of the lens would have been shattered? You're guessing that something impacted the lens cap and that shattered the filter, but that's just a guess. I find it hard to believe that inside a padded case something hit the lens cap hard enough to shatter the filter but not hard enough to damage the lens cap. I'm not a lawyer, but if I were defending the filter in court, I'd have a pretty stong case for reasonable doubt.</p>

<p>I have dropped lenses "face" down on concrete before with lens cap in place. Lens was fine. (Was not VR lenses though!) The plastic cap absorbs quite a bit of force. The glass in filters tends to be very thin so it won't vignette. That's why I don't consider them any real protection. But JDM is right about anecdotal evidence. All in all though, you see hundreds of lenses for sale on E bay that don't have filters and they are fine.<br>

Kent in SD</p>

<p>A shattered UV filter is a very rare occurance, with remote odds of it occuring again and it's also very likely that the random impact that caused the filter to shatter was so co-incidental that it's a one in a million chance occurance.</p>

<p>I can use the same logic to say that it's better to keep a UV filter on because of the very rare, random, chance / co-incidental occurance that did actually happen to me when I was buffeted by a rogue, huge gust of wind on a beach in New Zealand which lifted a single piece of twiggy driftwood weighing approx. 150grams and about 30cm long right up up off the sand and directly into the frontal element of my tri-pod mounted 17-35mm f/2.8 lens. As it turned out i did have a 77mm UV filter on which craked 1/3 across the pane of glass but did not shatter. The filter being there out front in all probabilty saved a similar nasty coating scatch to my precious lens.</p>

<p>There was very little beach flotsam and jetsom around this particular section of sand, the wind was workable except for this one freak gust which came out of nowhere which tossed perhaps the only piece of detritus on the beach fair and square into the front of my lens...... it happens..... it happened..... it's a result of a very random series of co-incidenses that might possibly never occur again.......</p>

<p>My point is that damage can occur anywhere, anytime to any equipment, wether you like protective filters or not, the occurance of one random event is no good logic to set a rule.</p>

<p>Let's face it: people understand freak incidents better than statistics :)</p>

<p>UV filters or No UV filters is not the question. The question is how did the damage occur? I ask this because a broken filter and scratched lens is the least of your worries. The Nikkor 70-200mm VR lens has 21 elements in 15 groups. Banging this type of lens around hard enough to break the glass filter can also cause miss-alignment of the internal lens elements. Also, my experience with this same lens and a Nikon NC filter is that I found my lens cap had come loose from the front of the lens. And, having the lens in the trunk of my automobile, I found the cap had scratched the NC filter. I was never so pleased to see a damaged filter. The $80 NC filter took the scrape instead of my $1700 Nikkor lens. So, my filters stay in place on my expense glass. Another time an NC filter saved me was in the Florida swamps. I had Deet all over me to keep the mosiquitos away. I reached into the front hood of my 80-400mm Nikon lens to remove the lens cap and it was not there. Big trouble, I touched the front glass of my lens with fingers full of DEET. Luckily, I had a NC filter in place. Let me put it to you this way. When I looked down at my employee badge hanging around my neck, the DEET was melting the plastic badge. The lens coating on any lens would have been toast with DEET on them. I just purchased a Nikkor 24-70mm f2.8 take a guess if I have an Nikon NC filter in place.</p>

<blockquote>

<p>The lens coating on any lens would have been toast with DEET on them.</p>

</blockquote>

<p>How can you know that? DEET can be a pain on plastic, but I have no evidence that it has any effect on glass - other than to smear it, so you would have had to clean it -- just like you would have had to clean a filter.</p>

<p>UV filters are a fetish for many with no purpose whatsoever apart from enriching the people that make them. For every person who thinks the UV filter has saved their lens there those who have had their pictures spoilt by unwanted reflections in high contrast situations.</p>

<p>This is an argument that is always with us. </p>

 

<p>I'm keeping my filters on. Personally, I can't see how a lens cap could transfer a force so great as to shatter a filter and sustain no damage itself. The lens caps don't even touch the filter glass; it's close but the gap is not negligible....Anyway, if you're worried about the cap damaging the filter, just remove the filter before replacing the cap.</p>

<p>I agree with Pete and Jose and others. I have this same lens and I keep a filter on my lens all the time. I doubt if the filter or the hood caused the mishap; it was something else. When not in use, I place an Op tech neoprene lens hood over the lens and filter before adding the lend hood, reversed. The lens hood fits snugly. Joe Smith</p>

<p>I agree with Laurentiu.<br>

And keep filters on those lenses on which I find them useful. Statistically based on nothing, but my empirical one sample evidence tells me this choice is sound.</p>

<p>I feel your pain, Chris, and certainly understand your knee-jerk reaction against filter protection. However, you must admit that your unfortunate experience was the consequence of a very mysterious fluke. You don't really know what happened.</p>

<p>I never used filters for protection while in the studio, but in the field, I always have. Sometime I have removed them at just the point of taking a picture and then screwed the filter back on for protection. I have had many incidents over my 5 decades of using filters where using one has saved the front element or threads of a lens. I've never had an experience like yours. Very unusual, I think.</p>

<p>For everyone's information, Hoya now makes an extra robust filter called the <a href="http://www.thkphoto.com/products/hoya/HD-01.html">Hoya HD</a> which is made of hardened glass and is much more difficult to break than a normal filter.</p>

<p>Someone is getting into your equipment and monkeying with it when you're not there. THAT's your problem, not filters.</p>

<p>I seem to remember having a lens repaired at Focal Pointe in Denver? who were able to repolish the elements (a lot more severe than you need) to repair the lens if you need that done. That said, I agree with the poster that said that without the filter the lens would probably have taken an even bigger knock. And then there is sand. I went to garden of the gods and the blowing sand managed to ruin a filter of mine that could have been the len's front element so I'm still for filters.</p>

<p>Remember the argument against seatbelts because you could be thrown clear? That could happen, but it's not where the statistical probability is, so I'd say you dodged a bullet, even it if did still bite you a bit.</p>

<p>I have rarely heard about the UV filter cracking and damaging the lens element. Maybe it was the quality of the UV filter. I always avoid putting on lens cap when the UV filter is on.</p>

<p>Chris,</p>

<p>I've been thinking more about your post and the particulars of this incident. Are the filter rings of the Hoya Super HMC pro filters thinner than normal Hoya filters? If so, that might have positioned the inside surface of the Nikon pinch lens cap even closer than normal to the glass surface of your filter when locked in place. Perhaps the very close proximity of the lens cap to the filter surface had something to do with the filter breaking? Just a thought. </p>

<p>Perhaps the <a href="http://www.bhphotovideo.com/c/product/101710-REG/General_Brand__77mm_Filter_Stack_Cap.html">male half of a stacking filter cap</a> would be better to use with thin filter rings instead of the Nikon pinch type filter cap. </p>

<p>I had a B + W break, but the glass was easly removed without any damange to the lens, just a lot of glass to clearn up. On impact the glass is meant to shatter outward alway from the lens as not to scrach the lens.</p>

<p>Haha, well, I see the issue is as contentious as ever. My apologies to those who feel that anecdotal stories are not useful. My intention was not to make any sweeping recommendations that world+dog should immediately dump their UV filters, rather to relate my experience and the personal conclusion that I drew from it. Anecdotal to you guys perhaps, but certainly not for me. Think of this as a single data point rather than an irrefutable verdict.</p>

<p>Robert, the offending remains are now on its way to the tip, but it did seem that there was approximately one mm of clearance between the inside of the lens cap and the filter surface when the cap is sitting naturally. It wouldn't take much of a knock to push the cap back onto the filter. Interesting suggestion regarding the stacking cap. It does occur to me that filters with a larger diameter are likely more fragile than their smaller counterparts, unless a heavier/tougher grade of glass is used.</p>

 

<p>In summary, I'm pleased to say that my 70-200 seems as sharp as ever, so no serious damage done.</p>

 

 

<p>Robin,</p>

<p>Here is part of my proof that DEET will damage lens coatings.</p>

<p>The link below has the following on page 5 of pdf:<br>

If your repellent does contain DEET, be aware that this chemical melts plastic and can severely damage cameras, binoculars, lens coatings, plastic tents and ...<br>

<cite><a href="http://www.amazon-ecotours.com/.../preparing%20for%20a%20trip%20to%20the%20Amazon-2009.pdf">www.amazon-ecotours.com/.../preparing%20for%20a%20trip%20to%20the%20Amazon-2009.pdf</a></cite><br>

<cite></cite><br>

here is a quote from another link:<br>

Spray your pants and socks with a spray repellent such as “Cutters” or “Off.” Repellants with high concentrations of DEET (70-100%) are most effective. You do not need to apply these to your skin, only to clothing. (Be careful as DEET will damage plastics and lens coatings).<br>

<a href="http://74.125.155.132/search?q=cache:eVPp1j-AxnMJ:ventcruises.com/system/tour_departure/legacy_itinerary/1087/309FCP.pdf+lens+coatings+DEET&cd=49&hl=en&ct=clnk&gl=us">http://74.125.155.132/search?q=cache:eVPp1j-AxnMJ:ventcruises.com/system/tour_departure/legacy_itinerary/1087/309FCP.pdf+lens+coatings+DEET&cd=49&hl=en&ct=clnk&gl=us</a></p>

<p>here is a quote from another link:<br>

"and can damage coated lenses"<br>

<a href="http://wingsbirds.com/tours/information/158">http://wingsbirds.com/tours/information/158</a></p>

<p>The people from the above links are not chemist or lens makers. They are tours operators and are speaking from experience. Personally, I would take their word for it. I know, know, experience does not count for some people. So, put the question to Nikon USA. I will post their answer when they reply.</p>

<p>Jose,</p>

<p>I agree they do say this. I have had DEET on lenses and no harm was done, although it is smeary to get off. I suspect that they say this because some lenses are plastic (some point and shoots) and it is generally unpleasant too. Damage also results when the user then carelessly scrubs it off the lens.</p>

<p>Still, do ask Nikon, it would be interesting to hear their reply.</p>

<p>Robin,<br>

Nikon replied to my question this morning. They more or less ignored my request to answer if DEET would harm the coating on the lens. They said don't use DEET as it will damage the camera's outer appearance. So, Nikon's reply won't settle this. It is interesting to hear that you've gotten DEET on the surface of Nikon lens and it didn't harm the lenses optic surface.</p>