Yet Another Post About My Issues With UV Filters
Yes, I’m sick of filter articles, too. But I come today not to educate you, but to mock others. Because yes, people continue to try to save a few bucks by putting a cheap filter in front of their $1,000 lens. And also because they buy what they think are good filters off of Fleabay or some used place and these filters aren’t what they think. This can particularly happen when you purchase a brand that makes different filters of differing quality.
How bad can it be, you ask? Well, today we’ll show you. Because someone had a 70-200mm f/2.8 lens that had been nice and sharp and then returned it because it suddenly got soft. They were kind enough to return it with their protective filter in place.
So the first thing we did, as we always do, was put the lens on OLAF, which is simply an array of collimated 5-micron pinholes. A good lens should show and an array of small dots or circles. But this lens showed an array of glaring star flare thingies.
No question, the customer was right, images from that lens had to be soft. But, just for completeness, we removed the filter, even though its label indicated it was a high-quality filter. Without the filter, it looked just like it should have.
Another thing we do on OLAF is slightly defocusing the image. In a nicely centered lens, the dots should turn into regular circles. This is that same lens above, just slightly defocused and looking just like we’d expect.
Then we put the filter back on without changing anything else.
If you have the slightest bit of visual imagination, you can probably figure out that there would be some bizarre, ugly bokeh with the filter on this lens. If you’re an optical geek, you might think that perhaps this filter isn’t really flat optical glass, it’s cheap sheet glass with a bit of wavy thickness.
There are a couple of things I should mention, just for completeness. We repeated the test with other copies of the same lens using the customer’s filter, and the results were identical. We also put a high-quality filter on the client’s lens and while there was a bit of blurring of the pinholes (longer lenses are more sensitive to filters), it was very minor.
So, if you want to know how much a filter that looks shiny and clear when you look through it can affect your images if it’s a cheap POS, well, there you go. Because if you looked at this filter, and looked through this filter, it would look just fine.
And another caution, just because a filter has a name brand on the side you recognize doesn’t mean it’s a good filter. For example, you can buy Tiffen or Hoya brand 77mm protective filters for $15-$18, or a better quality one of the same brand for about $35 , or top-quality for $70+ at a reputable dealer. The $15 filter is not the same quality as the $70 even though they both have the same brand on the side. And if you buy from less reputable dealers all bets are off because knock off cases for the higher priced filters are easy to obtain and the filter inside might not be what you think it is.
To learn more about what I think about UV filters in general, read my article on the topic here. There are circumstances where good-quality UV or clear filters are really a good idea. But there are no circumstances where a low-quality filter is a good idea. None.
Roger Cicala and Aaron Closz
Lensrentals.com
May, 2017
120 Comments
Ed Hassell ·
I started out with the no-filter crowd. And, for the most part, I’m still there; however, I have B+W XS-Pro slim, nano-multicoated UV Haze filters in sizes for each of my lenses just in case they’re needed. For general use, my lenses go naked. When I’m shooting in potentially foul situations and where there are airborn contaminates, around sand or water spray, the filter goes there first.
Thom Hogan ·
That’s a reasonable approach, IMHO. I use protective filters around volcanoes, for example, because I really don’t want what’s in the air to get on the front element of the lens: it can scratch and it can directly impact the coating. Sea spray in some areas would be another one where protection is a good idea.
Ed Hassell ·
I live in northeastern NC on the Albemarle sound — beautiful, but the middle of nowhere. Soil is either sand or clay or black mud. In the summer, humidity is 110% on a dry day; so, anything that touches the lens sticks. Sometimes, I just change filters and clean later.
walterunderwood ·
Haven’t had filters on my lenses for decades. Lens hoods are the best.
Jumping Pearl ·
a lens hood doesn’t protect against dirt / sand / smog particles
why do people seem incapable of understanding the difference
I’ve rather clean a $30 UV filter than rubbing off the coating on a $1000 lens
t_linn ·
Don’t get me wrong. I’m pro-filter. But I haven’t seen a $30 filter that I would trust.
Thom Hogan ·
No, a lens hood doesn’t do that. But go back and read my 14-24mm f/2.8 review. I subjected that lens to a lot of physical abuse. In the motorcycle shots I ended up with the built-in lens hood holding a lot of mud. Cleaned the lens and it’s perfectly fine. Rubbing the coating off modern lenses is actually difficult to do (though it can be done).
Meanwhile, I’m with Roger on this one: there’s not a single “protective filter” I’ve tried that doesn’t change the optical properties in a way that is negative. And that includes some high-priced ones. If you don’t care about the optical quality in your shots, then buy cheaper lenses! Don’t put a protective filter on it. With all the money you save by doing that you can easily afford to replace it should the worst happen.
El Aura ·
You might get better images with a damaged front coating then with a $30 filter.
Timothy Smith ·
Are you one of those guys that drives with a car bra.
Shield Block ✓ᵛᵉʳᶦᶠᶦᵉᵈ ᵗᵉᵃᵖᵒᵗ ·
a lens hood doesn't protect against dirt / sand / smog particles
why do people seem incapable of understanding the difference
I've rather clean a $30 UV filter than rubbing off the coating on a $1000 lens
I don't use my UV filter every time, but when I know I'm going to be in a place with lots of particles in the air, sand, dust, smog...a UV filter is a Godsend...and no .. a lens hood does not offer protection against any of these things
a decent Hoya UV filter for $30 is all you need, and the images with and without filter are indistinguishable
Jesse Lee ·
I presume you’ve been buying lenses often, too? Unless you only shoot indoors.
El Aura ·
And you are buying filters often? I bet if you do a survey of people using filters (for protective purposes) and ask them how long on average their filters last, I’d say the vast majority will say that they never even replaced a single filter.
Jesse Lee ·
You completely missed my point. The OP said he never uses filters so I presume that with frequent use he’ll have to replace his lenses often. What does that have to do with me buying filters?
El Aura ·
The OP only needs to buy a new lens when something damages the front lens element (in this filter vs no-filter context). But anything that damages the front element would also damage any filter on it. Thus if there are X front-lens-element/filter-damaging events, the filterless person would need to replace X lenses (or rather the front elements of X lenses) and the filter-using person would need to replace X filters.
What is so hard about this logic?
Jesse Lee ·
And you continue to miss the point… never mind, just pretend this never happened. Happy filter buying!
El Aura ·
Well, B refuses to acknowledge the simple fact that whatever destroys a lens front element would also destroy any filter on it. Thus any camera usage that leads to X destroyed lens front elements also leads to X destroyed filters.
B also assumes that most people have many of such events (without ‘many’ of such events, there wouldn’t be ‘often’ lens replacements). But B refuses to concede that only people which often need to replace filters would often need to replace a lens front element if they didn’t wear filters. Why that is so remains a mystery.
B should also contend with the fact C’s post got five upvotes while B’s posts got zero upvotes.
Jesse Lee ·
I applaud your stubborn stubbornness. Bravo. Well done.
Seriously, did I “refuse to acknowledge that blah blah blah”? Did I say ANYTHING remotely close to it? I asked ONE question and you go all Webster on me, and now I”m the one who’s at fault? Seriously?
Original message: “I presume you’ve been buying lenses often, too? Unless you only shoot indoors.”
I was challenging the OP that not putting on filters puts his lenses at risk, and thus he’s likely to replace lenses often. You’re the one who refuses to even read at the most basic level. I myself use filters and have rarely had to replace one, except for the two that were cracked when shooting in hectic scenes. How the hell did you arrive at me “refusing to concede that blah blah blah replace filters”??? ONE question, and you were able to derive all that. Keep up the good work. No wait, don’t.
And yes, upvotes are the qualifiers of life. I really envy all five of your upvotes. Only 95 left till 100!
Petrochemist ·
The problem with the Logic is that X for lens damage is NOT the same as X for filter damage. Filters will get damaged much more easily & can cause damage to lenses that would survive the event…
Sherwood_Botsford ·
In the Bad Old Days I would buy new UV/haze filters about once a year. But those were the days of soft multicoatings, and as someone who trying to photograph teens canoeing, hiking, rock climbing, dog sledding etc, my gear took a beating. (I have drowned 4 cameras and smashed two.) Lot of time rain was wiped off a filter with the corner of a t-shirt, or the cuff of my mitten.
Scott Soapbox ·
I’ll see your no filters and raise you no hoods, with a bias towards good flare resistant lenses. 🙂
Samuel H ·
I don’t use protective filters, but I do use ND filters a lot (I shoot mostly video). I tested them when I bought them and they were fine. But that’s when they were new and clean; I should probably do another round someday…
Franck Mée ·
I tested a low-cost polarizing filter last year. It worked nicely and was trouble-free at 50 mm, but the longer the focal length, the worse it got — and past 200 mm, pictures were absolutely awful and definitely unusable.
What’s fun is that some reflections looked strangely like OLAF’s pictures using this UV filter. So thanks for the reminder!
(For the curious ones who read French, I made a mini-report at the time: https://photo.h26.me/2016/05/07/pola-pola-bof/ .)
Chik Sum ·
Hi Roger, Any idea if the returned filter being a counterfeit one? since here in HK quite a lot of people have found some cheap fake B+W MRC which makes all lens look like BS
Roger Cicala ·
Chik, think this was counterfeit, or ‘replaced glass’ in a Tiffen ring. We stock mid-grade Tiffen protective filters (this was a Tiffen label) and they don’t do anything close to what this did. That being said, I don’t have access to the $15 range Tiffen filter, so it may be they really are like this.
Zos Xavius ·
I’ve used the cheap tiffens before and they are nowhere near as bad as this. Unless they have really dropped the ball on quality recently. All the tiffen filters I’ve tried were from the film days.
Laud Farter ·
Cheapo Tiffen is absolute crap. I borrowed a Leica 35 ‘Cron with a Tiffen UV filter and the loss of contrast, weird softening, and some “je n’ais sais quoi” were clearly visible. Also saw similar degradation from cheapo Tiffen on my Nikons. You could A/B it, it was so bad.
I also bought a used B+W UV/IR 486 that gave me weird colors on my M8; it had B+W markings but on the side, not the inside like their other filters. And then there was the Nikon UV that seemed a bit off, and the multicoating was different color than other Nikon filters I have. Don’t buy new or used filters without a good return policy.
geekyrocketguy ·
LensTip reported a while ago that the cheap Tiffens are worse than a clean sheet of window glass. So it really wouldn’t surprise me if this was a genuine product.
Jakub S. ·
If I was to shoot a rallycross (i don’t do that) maybe I?l put on a hardened protector filter. Otherwise I think any filter is a bad idea if not needed for some special effect (like polarizing).
Steven Leibson ·
Roger, thank you for moving the filter discussion from opinion to cold hard fact. The four OLAF images do more to inform me than years of opinion posts. I’ve been shooting SLRs since 1972 and back then, I always had a UV or Sky 1A filter on my lenses for protection and for the slight boost in IQ they supposedly provided. I continued this practice for a while when I switched to dSLRs but as the resolutions climbed above 8Mpixels, and with your previous posts on filters, I unscrewed them all and put them away. Now I will no longer even look back. Thanks for your posts.
–Steve
Edmond Wong ·
Is there a new updated list of some of the newer models other than just the one on lenstip.com from 2007? I recently bought a Hoya Fusion Antistatic Protector. I can’t tell from looking at the Hoya site if this is equivalent to one of their more expensive ones or not. It’s made in japan. I was going to go without a filter but I was planning on doing newborn pictures and they might pee on my lens.
Colorado Kid ·
Ed, you don’t have to get that close, get a tele if there’s danger. 🙂
Al Majauskas ·
Excellent article Roger. What an eye opener. I’ve always used filters, mainly to protect. Now I’m wondering if filters are responsible for back/front-focusing issues or similar out-of-focus issues blamed on poor lens design. I’ve noticed my long lens won’t focus with polarizing filters. Seems now there’s lots of filter problems. Also, how vulnerable are naked lenses without these? Are there simple uncoated glass filters available? Are there filter reviews out there testing for filter acuity? Thanks.
Eric Bowles ·
Uncoated filters pose an additional set of problems from reflections and flare. As long as you use the lens hood and lens cap, and use a filter with adverse conditions (like blowing sand or salt spray), you’ll be fine. Take a look at Roger’s article about reassessing the risk associated with damaged front elements as the cost of repair is slightly changing the view on protection.
Al Majauskas ·
Thanks Eric. You’re saying uncoated filters cause other problems related to quality. Good to know. I shoot mainly prime on D7000 with my old 24mm 2.8 Nikon with a fairly wide lens hood and I’m going to test picture quality w/o filter and see if the focusing issue is caused by the filter. I might just try shooting without and see if things improve. Another concern is the inevitable finger prints on the actual lens and how to clean without wearing out any coatings. Seems on this you’re between a rock and hard place – protect your lens and suffer quality or damage the lens with dings and scratches keeping it clean. I haven’t put this much thought into such an innocuous little object in 40 years of shooting.
Eric Bowles ·
I shoot about 35,000 frames per year. Over the past 5 years, I’ve scratched a front element slightly on one lens – cleaning a mud splash that was completely a surprise – and the scratch is very minor. I almost always use a lens hood, and increasingly use a lens cap when I am carrying an extra body or walking through areas that are rough or through brush. I’ve never seen any wear on the coatings – they are surprisingly durable.
Roger Cicala ·
I don’t think it’s a problem in general, but phase detection is comparing light paths from opposite sides of the lens, contrast detection, well obviously contrast. I think a BAD filter could interefere with either, but I don’t think a good quality filter would.
Les ·
Al,
re: “my long lens won’t focus with polarizing filters”
The first thought that comes to mind is that you are using a regular polarizer instead of a circular polarizer.
Pete Myers ·
Hi Roger:
Let us mention one other aspect in regard to filters; plastic filter threads. I truly think we should all stop buying any lens with a plastic filter thread until the industry reverts back to metal. For those of us that use filters at altitude (deep cut UV) or contrast filters for black and white, the industries move towards all-plastic filter threads has been a disaster.
Pete
Roger Cicala ·
Pete, that’s an interesting thought because when I first saw these images, I wondered if the filter was cross-threaded and that was causing the problem. That’s why we did comparisons on other lenses and with other filters on this lens.
Carleton Foxx ·
I would think plastic threads would be better because they wouldn’t be as apt to get frozen to the lens threads—and even if they did, it would be easier to hacksaw through them. What makes them especially problematic…?
Pete Myers ·
Hi Carleton:
You are asking a good question. High-end filters are always made of brass, with brass threads. Using metal threads against plastic tends to quickly wear the plastic, and the thread becomes “sloppy.” Remember, we are adding an optical element to the lens, so it has to be perfectly aligned with the front lens. Any play in the threads and mis-alignment will lead to an astigmatism in the lens response. As Roger and his crews have grandly demonstrated, it does not take much to greatly effect the lens response.
Also, plastic is injection molded, and there tends to be a bit of heat warp and variation in tolerances as a byproduct of the process. Brass threads are machine cut, and particularly with brass tend to be a precision component—like the movement of a fine analog watch.
For those of us that do monochrome work not derived from bayer color sensors, contrast filters are an essential and an every day component of our work. We are constantly changing them.
Pete
Brandon Dube ·
If you put a true window in front of a lens (both surfaces very flat), it doesn’t matter how you orient it, there will be no impact on the in-focus image. If you have a cheap filter that isn’t actually flat on both sides, its orientation will matter.
Pete Myers ·
Hi Brandon—I will defer to Roger for explanation, as I am just a guest on his Blog. Suffice it to say, I hate plastic filter threads, and I think it is a poor reflection upon the industry.
Pete
Eric Bowles ·
Roger – great report!
Do you have any suggestions for testing filters? It’s easy to buy higher grade filters and use them only when needed, but the risk of cheap knockoffs is something that may require testing. Obviously I don’t have your friend OLAF.
Roger Cicala ·
Eric, I think I’d use a longer lens (this one was more dramatic at 200 than at 70) and maybe look at out-of-focus lights. I think that should be a pretty sensitive test.
Thom Hogan ·
It’s an excellent test for eyesight, too! Find some small LEDs and focus on them from a distance with that long lens. Then check the smear with and without the filter. Both in focus and slightly out of focus as Roger did with Olaf.
Jeff Allen ·
Then after years of doing this wonder why your eye sight has degraded. Small point source LEDs are very bad for the rear of your eye you should never look at LEDs without them being diffused.
Robson Robson ·
Hello Jeff, LEDs typically have viewing angles large enough so that you shouldn’ t be blinded. And if they have large enough a viewing angle they tend to be not laser diodes.
So you don’ t have to look into a laser with your remaining eye to check your filter… 😉
John Gaylord ·
Beware of “multi-coated” only on one side because reflections from both sides can degrade quality.
Edmond Wong ·
How can you tell if it’s one side or both?
Sherwood_Botsford ·
What you really care about is reflection.
Try this:
Put the filter down on a dark surface. Use a laser pointer and shine it onto the surface at about a 45 degree wall, and go look at the reflected dots on the wall.
The overall brightness of the dots tell you how good the anti-reflection coating is. (For comparison you can use a glass from a picture frame)
The brightest dot is the front reflection. The next one is the back reflection. If you see a third one it’s the 2nd back reflection.
Flip the filter over and try again. If they are different, then they aren’t coated the same way.
Bob Mahar ·
So what were the results with a high quality filter? All we have proven is that this filter sucks, not that “better” filters are, optically, better – a photo would have driven the conclusion home. As for longer lenses being more sensitive to filters, what do you mean? Again this is a very “folksy” / subjective way of describing it. “My lens is allergic to cheap filters.” My objection is not that the results or the conclusions are wrong – they are right AFAIK – many cheap filters are horrible. But layering on subjective / non-scientific verbiage is not as helpful as a photo of OLAF with a “good” filter in place. I bet its still not all that great.
DilbertJ ·
He has another article linked where he shows that info. The purpose of this article is to reinforce a standing opinion that cheap filters are no good.
Patrick Chase ·
The other article only shows before/after results from a good filter on a 50/1.2 (42 mm entrance pupil), which is a relatively filter-insensitive geometry. That specific lens doesn’t have terribly high MTF to begin with, which makes it difficult to spot modest attenuations from the filter (a 10% loss is a lot harder to see when you’re starting at 20% than when you’re starting at 80%).
What would be nice to see if possible is a similar comparison using a 200/2.8, 400/5.6, or similar. Good examples of such lenses have pretty high MTF without the filter, which makes the degradation more noticeable (both visually and in measurements). In addition their large entrance pupils mean that they will be more sensitive to things like flatness across the entire filter.
FWIW I mostly use B+W XS-Pros now (same filter pictured in this article). I also have a couple Hoya HD3s (their top of the line filter) and an eye-wateringly expensive Heliopan SH-PMC. They all seem to work, with the B+Ws being the cheapest of the lot.
Carleton Foxx ·
What are our thoughts about the Canon- and Nikon-brand clear filters? I have a couple of Nikon NC-Clears and they seem fine, but now I’m not going to be able to sleep at night…
Roger Cicala ·
I’ve never used them or looked so I have no idea.
Thom Hogan ·
Might depend what filter you’re talking about. For example, Nikon designs some of the exotic lenses with drop-in filters so that the filter itself is part of the optical formula (i.e. you need a clear placeholder there if you’re not using one of Nikon’s drop-in filters).
If you’re talking about front-of-lens filters, then I’m not sure.
Carleton Foxx ·
I just meant their Plain Jane 77mm NC clear screw on filters. Apparently Nikon is not doing a good job of making it known that they even have them available.
I won’t even ask about the effects of their old radioactive soft-focus filters….
David Bateman ·
I stoped using filters in 2008, after I purchased a $70 filter to protect a $150 lens. I stoped, looked at possible issues of using filters or not and switched to stop. Even on my lenses over $1000, the hood does the best job for the protection I would need. But I never shoot in dust storms or at the beach, so I know others milage may vary.
Chaitanya ·
Only filters I use are Cpl and nd but thats a necessity while shooting landscapes in tropical India. Also another reason for filter for me is most canon lenses need filter to complete weather sealing and using those lenses in western ghats during monsoons without filter is a fungal nightmare.
Zog2012 ·
I was hit 15 times by pucks in NHL, AHL and ECHL arenas. I could shake them off and laugh about them. Once a puck tipped off the glass and hit my in the head and the knee and all the facilities people near me had a laugh. 16th time at the top of the aisle where no pucks go, a fluttering clearing attempt hit the front of my 70-200 VR I and I heard a crunch. Had a metal B + W UV filter on (single coat, I later put the mutli coat one on it). Puck shattered the glass filter and dented the metal ring, but did no visible damage to the lens. There was some focusing lag after so I sent it in under warranty, but there are instances where having a solid, metal high quality filter is a must.
Michael Clark ·
Because that really thin, flat filter made out of BK-7 is just as strong and resistant to shattering as that 3/4 inch thick piece of curved, higher grade glass called the front element, right?
And as you discovered, the greatest concern about impact damage is to internal alignment of lens elements and other internal moving parts.
Zos Xavius ·
This is what I’ve been saying for years. So nice to see someone prove it with actual tests. Hoods are the way to go.
Mike Jackson ·
I stopped using UV filters after my first lens drop… somehow the filter scratched the front element on a 2 foot drop. I do consider them when I’m going into an environment that will have flying particulates, but that is very rare.
Thom Hogan ·
Yes, this is one the things I mentioned in my article and got lots of flack about. But I’ve seen it multiple times in the field where a drop causes the filter to shatter and the shards scratch the lens front element. Then the argument starts “but without the filter the lens would have shattered…” No, it wouldn’t. This gets tricky because every lens is different, but there usually is a cost difference between repairing a lens that has front ring and alignment damage from a drop and one that needs the front element completely replaced.
Steven D. Keirstead ·
Yes, I once had an L37c UV filter shatter and scratch the front element of a 105mm Micro Nikkor when I tripped and my Nikon hit the pavement. It was in an unpadded backpack, and the lens cap was on. The lens had a rather inexpensive fron element. I think it was only $25 at the time, about 1992. Since then I have not used protection filters regularly.
Rodger ·
promaster HGX filters all day everyday
Nick Spiker ·
On another note, why do people insist on UV filters? Silicon is not very sensitive to UV, plus the internal camera filter usually blocks it. All of the UV filters I have tested don’t even block UV anyway. I think the idea is quite pointless and irritating when you actually need to block UV. Protective filters on the other hand, are a good investment, and should be considered in the budget.
Sherwood_Botsford ·
UV is a hold over from film days I suspect. I would buy what was marketed as a haze filter, which blocked UV and also had a faint pink cast to partially cancel the effect of smoke and terpines off the forest (blue smog) At that point I shot mostly Fuji slide film as I preferred it’s rendition of greens. Anyway, while digital cameras are not particularly sensitive to UV, film was.
UV isn’t hard to add. Tru-vue museum grade (very clear, UV blocking) runs 30 bucks for an 11×17 sheet small quantity retail, so a 75mm filter’s additional cost at this price would be under 2 bucks. And since it is likely just an additional compound in the glass melt, it’s almost certainly peanuts.
Mike Barrett ·
Here is my rant with filters…. Pricing… Let me see if I have this right. Take a look at the thickness and geometry of the glass elements of a modern lens, the complexity of zoom rings, centering, shims, focus rings, coatings, etc, etc.
And then on a per piece of glass basis, a single piece of thin (easier to make clear, etc) glass costs 2-3x that of piece of glass in the body of a lens. (ps I used to work for a glass man’f trust me on the then vs. thick chunks of glass). It isn’t the cost of the glass, the precision in which the shapes are ground (flat vs. complex curves on both sides) that drive up the price of the filter… 🙂
Capitalism at play…. certainly…. and stupidity that we will buy 1 piece of glass for 10%, 20% of the cost of a 23 element lens. These filters fit on lenses from all man’f, if anything they should have a better economy of scale. Look at how many lenses have 77 or 82 mm threads, how many copies of Canon lens element 4 in the xx-yy zoom does Canon make vs. a filter maker’s 77 mm UV, Clear filter…. I suspect far more then C,N,Z,L,S, etc make of any one element of their zz-yy zoom. Yet the lens maker can make several more, align, shim, etc and on a per piece of glass basis deliver a superior product.
Ok rant over.
Brandon Dube ·
Why even keep it relative? It takes ~1/5lb of optical glass to make the filter and these are all made of BK-7 at $10/lb. The finished and coated element in a good UV filter would be less than $10 at volume. A more complex filter is not significantly more expensive.
Mike Barrett ·
ok, I guess…… Even IF it takes 1-5lbs of glass per filter I think is your point?
Brandon Dube ·
my point is that the filter requires about a fifth of a pound of optical glass to manufacture, which will cost about $2 per filter. Grinding and polishing a precision flat at volume has nearly zero cost, and the coating will be << $10 at volume, likely < $1.
There are few glass manufactures – outside of exotics you will only see Schott, Ohara, Hoya, and Corning. I do not think you worked at a glass manufacture in a technical or production role from reading your comment.
Steve Oakley ·
only my 17-55 has a UV filter on it. its for more run and gun stuff and gets exposed to a lot of dust, handling ( fingerprints ) and potentially rain. trashed a filter once ( rock hit ) already so it was a cheap investment. the rest of my glass almost never has a UV filter because of cost and the potential issues the extra surface adds. One could get a 82+MM filter and a set of adapters to go smaller for those once in a great while times when some protection is in order.
Max Rockbin ·
I discovered your blog a couple years ago after googling for whether UV filters were worthwhile. I’ve been reading you ever since. So (at least from my point of view), you’re not just spitting in the wind.
rb763 ·
I started using filters when I put a scratch on one of my lens’ front elements. So today after reading this, I thought I would try a few shots without the filter on my Canon 70-300 L lens which I was using on my Sony a6500. I never even got to the image quality comparison because the first thing I noticed was how much removing the filter improved the autofocus performance. Night and day!
Lewis Johnson ·
Thanks for reporting this.
I was going ask if slow or inaccurate was a theoretical issue after seeing the OLAF images above. Af, particularly contrast af isn’t going to like the funky flare.
Eddy Kamera ·
So I assume that filters of other types such as ND and CPL are also not created equal? I have a couple of cheap ND filters.
Roger Cicala ·
That would be correct 🙂
BattleBrat ·
I use heliopan UV/IR Digital cut filters, and my lenses spit out razor sharp images so I guess I’m ok laughs
DrJon ·
One of the things that annoys me with all but a tiny number of UV and Protection filters is reflections from the inside of the filter for Night shots with bright lights in them. I believe it’s the lit-up sensor that is making the reflection back to the filter. I found the Hoya HD ones to be unacceptable (to me) and really only the posh B+W ones work well for me. The other answer is to remember to remove the filter for Night work, of course.
Thom Hogan ·
This has long been an issue with digital: there’s a flat piece of glass sitting over the sensor. Originally, it was highly reflective. These days, most of the camera companies have addressed the reflectivity some, but it’s still reflective. What they also have been doing is to reverse coat some lens elements so that you don’t get that bounce back of pinpoint sources like that. But most filters don’t do that. So any light that reflects into the back of the sensor—and some of that may even come off the front element of the lens, despite coatings—can cause this issue.
DrJon ·
These days is it the sensor glass or the sensor? One is much harder to coat. With the Fujis when shooting into the sun you can (rarely) get an (annoying to remove) patterning effect on images that appears to be from a reflection of the sensor, not the sensor glass?
Example: https://www.dpreview.com/forums/post/59383192
Thom Hogan ·
Technically, most sensors have microlenses as their top layer these days, which makes for a textured top, even though that’s a very fine texture. It’s the UVIR (and sometimes AA) filter that sits in front of the sensor that’s one of the issues. Yes, you coat it, but coatings are 100% effective.
Ian ·
Holy *bleep* Lensrentalman! That’s amazing to see that it affects it that much and reminds me of the old saying, “If you can’t afford the hub caps, you can’t afford the car.” Thanks as always for the informative and entertaining post!
The3o5Flyguy ·
I was a fool if to think adding a $10 piece of glass infront of a $1000+ piece of glass will produce a sharp image…. I took my filter off my lens once to clean off a smuge forgot to put it back on. I went shooting and noticed the images were sharper than they had ever been. Since then, my filters have been colecting dust
Jumping Pearl ·
my images with and without Hoya UV filter are indistinguishable, and the benefit of keeping the front lens element clean in dirty environments is great
this idea that there are tons of bad UV filters out there is baloney, yes some exist, but most peple know you shouldn’t buy a $10 filter
most people are buying the $30-$50 hoya filters from amazon and they offer amazing protection for environments with lots of particles, dust, sand or smog
cleaning a $1000 lens with the risk of removing coating = nightmare
cleaning a $30 UV filter = not a problem
Thom Hogan ·
“Indistinguisable.” Perhaps indistinguishable to you, but perhaps not to others. That’s the real problem here. We get a lot of anecdotal “don’t see any difference” reports. I get those with filters, lenses, sensors, raw converters, you name it. Trained eyes see something different than untrained eyes. And measurements say something different than subjective evaluation.
As for film, we used UV filters until the 90’s because film had a significant UV response. So as you moved to higher altitudes you got different results. Somewhere in the 90’s most films stopped having significant UV response. DSLRs have had UVIR blocking filters over their sensor from the beginning. There is no significant UV response in a DSLR that hasn’t been modified.
El Aura ·
How large was your usual viewing size with film and how large is it now? The largest prints of my film photos is smaller than my current monitor. And I don’t even have a 4K or 5K monitor, having one of these will further increase the amount of detail I can see, in particular since large prints tended to be looked at from a larger distance than the typical viewing distance for computer monitors.
Plus what Thom said about actually getting an IQ benefit from an UV filter during almost the whole film era. I had UV filters during the film era but after I did not manage to damage the surface of a single one during about 20 years, I decided that filters were an insurance with a very bad cost to benefit ratio (benefits being the saved lens repair costs multiplied with the probability of an incident occurring). There are other insurance-type situations where I get a much better benefit to cost ratio.
taildraggin ·
I tested a new Hoya HMC UV(C) last weekend – obvious impact to sharpness & contrast. Roughly, degradation is about the difference between my best (85/1.8G) and “worst” lens (35/2D) at middle apertures.
Shield Block ✓ᵛᵉʳᶦᶠᶦᵉᵈ ᵗᵉᵃᵖᵒᵗ ·
my images with and without Hoya UV filter are indistinguishable, and the benefit of keeping the front lens element clean in dirty environments is great
this idea that there are tons of bad UV filters out there is baloney, yes some exist, but most peple know you shouldn't buy a $10 filter
most people are buying the $30-$50 hoya filters from amazon and they offer amazing protection for environments with lots of particles, dust, sand or smog
cleaning a $1000 lens with the risk of removing coating = nightmare
cleaning a $30 UV filter = not a problem
amazing that when we shot film, no one was whining about UV filters, and now UV filters are suddenly a bad thing? I don't know how we managed in the past!
Jesse Lee ·
Thanks for the clearly-understandable article. Those images made the message abundantly “clear,” no pun intended.
Mike King ·
I teach photography and in the last year I have had to remove the broken bits of cheap filters from expensive lenses on four separate occasions. Four times. It’s a pretty small enrollment in our program, too. And did I mention–four times? Oh yeah, for novice photographers, replacing a cheap filter beats replacing an expensive lens. I always suggest they replace said sad, broken, cheap filter with one of better quality for the next go around.
jrconner ·
I don’t have OLAF luring in my basement, but my rough and ready tests, and Roger Clark’s at clarkvision.com, confirm R.C.’s observations. Unless I’m shooting in a sandstorm or in similar conditions, I do not place a protective filter in front of the lens. And I don’t use a polarizer as much as I used to.
david ·
I’m confused by the anti-filter absolutism of some of the comments. I think this excellent article proves indisputably that bad filters can massively degrade image quality. At the same time, Roger has also said, “A good filter should avoid most (not all, but almost all) effects regarding ghosting, flare, and reflection. It shouldn’t affect sharpness even at the highest level of measurement.” He has shown MTF evidence demonstrating that. And he has pointed out that the rising cost of lens front elements makes the use of filters more of a judgement call. Using or not using filters is a practical balancing act, not a religious belief.
Roger Cicala ·
What he said. Thank you David!
dale gravatt ·
Excellent information – thanks Roger. What about Canon’s professional “L” lenses – many of whose weather resistant properties remain incomplete without the addition of a front filter? A dilemma?
Roger Cicala ·
Not really. Nothing here says don’t use a filter, it just says don’t use a $20 filter. And don’t buy your filter from anything other than a reliable source.
individual1 ·
First, I’m with the guy that thanks you for the empirical evidence (turning to your original article now). Second – I looked at the OLAF images and wondered if there is a creative way to use the cheap-filter effect… (laugh).
Claudia Muster ·
Very impressive, indeed. It would have been interesting to also see an OLAF picture with a quality filter for direct comparison. (I’m aware that you have published MTF curves in the linked article and didn’t find any degradation worth mentioning.)
Roger Cicala ·
Claudia, I’m going to go buy a bunch of filters and do this with all of them. It’s a fairly crude test, but at least should give us a ‘pass-fail’ kind of grade on them.
Notna ·
Great, it’ll be interesting to see just how big the difference is between a crap filter and a decent or good one.
Bob B. ·
I buy the best lenses that are available when I can afford them. I put the high quality B+W Clear MRC Nano filters on them.
I get:
Great images
Peace of mind
High resale value
It’s a personal choice. If I have a great shot. No one asks if I had a protective filter on my lens. Ever.
I have never had images where I think that there is a problem and where my B+W filter was the cause.
🙂
dale gravatt ·
“If you can’t do it right, don’t do it at all” – I heard that thousands of times from my grandfather – a meticulous engineer. Roger’s presented evidence is too strong to disregard – within the described parameters. When time permits, I’m going to shoot “with and withouts” on all present lens/filter combos (gulp, over 80 lenses). Aside from your general useage, have you shot careful comparisons with your B+W’s – with and without? Many of my filters are B+W’s. So many projects, so little time. Ugh.
Ben Brayev ·
any idea if the compatible 105mm protective filter of the new sigma 500mm f4 is as bad as the rest of them?
Mosawr Team ·
Thanks for the article. Shoot, this means I need to change my cheapo Tiffen UV filter.
Roger Cicala ·
Yeah, I think so. Some repeat testing showed I was probably wrong: this was really a cheapo Tiffen, not a counterfit.
taildraggin ·
Timely. I pulled a circa 1979 52mm HMC UV(0) that “looks great” from my Nikon FE/50 1.8 AIS last weekend and put it on my excellent DX 35 1.8G/D3300 beach camera. Lot’s of gritty dust at the beach shooting daughter’s volleyball games so it makes sense to put a filter on. How bad could it be? In the same geek moment, I was checking out my new 50/1.8G and compared images. The 35mm, wide open now had green fringing around *all* sharp, contrasting edges and contrast was down. Wow, that is a REEELY BAD filter. Looked perfect. Pulled the filter and was greatly relieved to get my lens back.
This prompted me to check all my len-filter combos, pretty thoroughly. 1) all the filters had a noticeable sharpness/contrast impact. The best (singh ray, B+W, high-end Hoya) were tolerable-to-modest. 2) Old film era filters are suspect. You wouldn’t believe how bad the old Hoya was. The new HMC UV(C) had only modest (acceptable) impact.
This confirmed what Roger writes; use only when needed as a dirt cover. This means 2 things to me the mid-level Hoya HMCs are bottom line acceptable, but also the ones I want since I’m only going to use them in dusty conditions.
I also use hoods to block bumps – I don’t know if it’s helped, but haven’t scratched a front element in 40 years of (amateur) photography and if they stop any stray light, all the better.
Jeff Allen ·
Sometimes things need to be set in context. Roger mentions most scratches will not photograph shooting into the light on front elements. This is also true of good quality filters including resin filters that some people have an issue with. Resin filters made well use the same optical quality resin used in glasses such as Acomon AG Rav 7 and are pressed between ground & polished steel sheets carefully aligned, whilst the filter is still warm from dyeing.
They undergo flatness testing, MTF readings and spectrometer testing EVERY filter.
All that said Panavision make a filter holder that tilts the filter slightly to minimise veiling glare shooting into the light, those images are projected far larger than most stills images and whilst we do not dwell on single movie frames none the less focus is often critical.
Filters have a place, they are not ideal but sometimes they save an otherwise mundane shot and artistically can transform a scene (think reflections on water, over bright skies, boosting blue skies etc)
Brandon Dube ·
I very strongly doubt they test the surface quality of every filter adequately. To do that you need an interferometer, the setup for which will cost a quarter million dollars. You don’t use a $250k machine to test $25 filters.
You wouldn’t (and can’t) MTF test a filter, since it isn’t image forming.
They may spectrally test every filter, but that would be outside the norm. Typically one sample flat is taken from each coating run and taken to be representative of all of them.
Tilting a filter that is truly flat on both sides won’t do anything for a subject very far away.
Jeff Allen ·
Lee Filters spectrally test every filter, every filter is tested in front of a 200mm lens with an MTF (the lens is image forming and filters can affect MTF reading of that lens). Every filter is tested for flatness.
Most scratches will not photographic unless very deep as they are too far away from the plain of focus.
Brandon Dube ·
I found this video,
https://petapixel.com/2016/09/28/see-lee-filter-cast-tested-hand-dyed-factory/
At about 3:50, that is not an MTF test. It is a limiting resolution test with a USAF target. It is impossible to measure an MTF from that target. It would take a pretty severe error in flatness for them to see it in that test — it is antiquated and insensitive.
Later you can see them use a konica minolta spectrophotometer to measure transmission. It does not appear that they use it for a spectral test.
Later in the video you can see the filter cleaned with acetone. This should never be done, as acetone eats resin – https://www.youtube.com/watch?v=dyjnJaTU70I It doesn’t take long to remove the few nanometers of thickness that will ruin the optical performance.
Eeseekeal Flamthrower ·
My opinion is that if a photographer shoots in messy situations where it might not be easy to protect the lens/camera then a filter makes sense. Also, on many lenses, the lens is not deemed ‘sealed’ unless a filter is in place. I take care to protect my gear, mostly shoot in the dry desert, and I’m not a pro with heavy duty usage. I don’t use a filter, and I don’t have any scratches or wear on my front elements. I also ALWAYS use a hood.
Dmitry Anisimov ·
Of course. 200 mm is telephoto. The same filter wouldn’t have been a problem on a 21 mm lens xD
individual1 ·
Looks like Nikon has taken the bait…https://m.dpreview.com/news/0172115929/nikon-launches-arcrest-protection-filter-line
jamesm007 ·
Its soooo simple. Too much time wasted (mine to). I agree with Shield Block. Buy a quality (Hoya B+W) filter and test it out. That’s what I do and have never lost picture after I determined the filter was fine, no IQ effects. I also keep the front clean. When you are a little anal, like me with cleaning, a filter that does not hurt IQ that I can see is better than rubbing the expensive front element of a lens over time; especially over time. I don’t use filters on my weather resistant lens that have a special coating to repel water. Other than that…
Sherwood_Botsford ·
Would this work?
For people who want something like OLAF, but who have thinner wallets, try this:
Take a chunk of dark matt board, or any other dark background.
Buy a bunch of the tiny christmas ornaments that florists like to use. If you read this at the wrong time of year, steel ball bearings work too, but tend to escape.
Illuminate the target with as close to a point source as you have. A single 1 watt unfrosted LED works well. An unfrosted halogen bulb is probably what most people can find.
A small round object will produce a very tiny specular reflection. The dark background produces good contrast.
Sherwood_Botsford ·
For those of us who don’t have an OLAF in the closet, would the following work well as an alternate testing target?
Take a sheet of black or middle grey (so to get reasonable light meter readings) and glue onto it either a bunch of small christmass tree ornaments, or steel ball bearings. Iluminate with a spotlight.
Randy Box ·
Just came in this morning, realizing my dissatisfaction with my new 200-500 VR Nikon lens is to due to a B&W F-Pro 95mm MRC 007 clear filter (Both BNIB at same time March 5th, 2019). I could get a sharp image 1 of every 10 pics, maybe. I pulled the filter off and was shocked that almost every single pic was sharp. It was not so much the filter affecting IQ as it affects my AF.
Just last night, I had even written a letter to the retailer I purchased the lens from asking to swap it and see if I had a “soft” copy. This lens has never taken a single pic without the filter until this morning.I was impressed by the notion of keeping my front glass new by never exposing it to anything that would need to be wiped clean. It made sense that it’s better to damage a $100+ filter than a $1,000 lens. That argument still holds water.
Sorry to resurrect a 2 year old thread, but when I went Googling, here’s what I found.
Philip ·
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