To filter or not to filter....

Do I really need a UV filter? Is it only for lens protection? Can I get away without using one?

Do I really need a UV filter? Is it only for lens protection? Can I get away without using one?

Filter or No filter, Hmmm. This is a classic Trolling question. There are True Believers on both sides, and IMHO, no definitive proof to support either as absolute.

Any filter of any kind has some optical cost. Adding more glass, no matter how expensive it is, inevitably will have some tiny effect on optical quality -- reflections, additional surfaces, grease-, whatever.

 

However, I was awfully glad I had a protection filter on an expensive lens when the kid put his iced milk cone onto the lens surface.

 

The effect is small, and protection is good. Some of my filters have given their all to protect the lens they are on. For really critical work, or in exotic light situations, I remove the filter.

 

Here is a pristine Exakta-mount [yes, really] lens from Canon and the filter that kept it pristine

 

 

and here is a filter that protected the front element of my expensive telephoto zoom

Edited May 21, 2020 by JDMvW

To be more precise. I just bought Sigma 70-200 F2.8 Sport lens. So from impact or dust protection, I would consider one, but what would the negative IQ side of the coin be? Would I see any noticible differences in my photos from having one on?

To be more precise. I just bought Sigma 70-200 F2.8 Sport lens. So from impact or dust protection, I would consider one, but what would the negative IQ side of the coin be? Would I see any noticible differences in my photos from having one on?

Try and see with your skills and your gear. No film, no processing. One guarantee with a filter for protection, you will clean your lenses less. You must decide what works for you. No one else can. If you don't care to try, flip a coin.

I should also have mentioned again that a lens hood can often also serve as a cushion for hard knocks. If it fits the lens, it will have no detrimental effect at all -- quite the contrary.

I keep good quality filters on all my lenses: typically UV. Mostly all are top line Hoya. Been doing that for years, and I still have a collection of Skylight Filters which I used for the same reason generally 'protection'.

 

My view is that in the real world no one can pick in an A/B between two digital images using a UV or 'protector' - 'Filter on' and 'Filter off', PROVIDED that the filter used is high quality AND the lighting and/or shooting scenario did not dictate the Filter to be removed as Best Practice.

 

On the second point of Best Practice - IF you choose to use a Filter for protection, then you should learn in what situations even an high quality filter might cause an adverse result – in that situation you should really consider removing the Filter. Generally it is because of the lighting of the scene. As two common examples: shooting into the Light a Filter can exacerbate Veiling Flare and/or general Lens Flare and/or Flare Spots; shooting a dark scene with a smaller area of bright light or a bright reflected image a Filter can manifest a Ghost Image

 

My meaning of 'protection' will be different from others. Over the years I have used my gear in many public places, places where there was beer, food, people having a good time, children’s fingers and investigative pets. Also, even with digital, I carried no fewer than two cameras, often three. As a consequence, I’d rather the Filter on the rig dangling off my shoulder be investigated by the child, or dog, or it banged on a table corner, than the lens’s front element taking that punishment. And my cleaning device used on site would be my handkerchief, table napkin or paper towel – again I’d prefer to use a few drops of soda water and my handkerchief on a Filter and not on a Lens.

 

In any event I always use a Lens Hood, except for some macro and copy work and a lens hood offers protection, typically more protection for a Prime Lens than a Zoom and typically more protection for a Longer Focal Length than a Shorter Focal Length, due to intrinsic Lens design mathematics.

 

I had (now passed) a good friend, huge sports shooter, he carried the three Canon F/2.8L and a 400/2.8L and two Series 1 Bodies in a duffle bag, complete with coke cans, bananas, sandwiches in plastic wrap. All his lenses had their hoods on, but rear lens caps were chucked in the garbage bin. This gear all bounced around happily in his bag and he made brilliant images – it was his ‘tool kit', nothing more noting less and from his point of view he took “adequate” care of his tools. My idea of ‘care of my tools’ is simply different to my mate’s.

 

You’ll probably get advocates for YES FILTER and NO FILTER – my points are neither an attempt to convert nor defend, simply explain what I do and why.

 

WW

There are True Believers on both sides

That made me laugh.

and so did this -

when the kid put his iced milk cone onto the lens surface.

Here in New Zealand (Southern Hemisphere for you Nordies) our sun is different. We do have a huge ozone hole, so there is vast amount of UV around, hence most of my images in bright sunlight will have that milky look to them. I always try (when I can) shoot (while in bright sun) so there is a darker background behind the subject. This usually gives me better contrast and makes the subject pop more

Generally it is because of the lighting of the scene. As two common examples: shooting into the Light a Filter can exacerbate Veiling Flare and/or general Lens Flare and/or Flare Spots; shooting a dark scene with a smaller area of bright light or a bright reflected image a Filter can manifest a Ghost Image

 

Good info William, much appreciated.

 

In my early days I knew nothing about that and only kept the UV filter on for protection and not having to clean the lens so often. I left it on all the time but now remove it when it's not really needed like on dull days or close-up shots. I struggle though cutting down haze in landscapes, mountains in the distance. Is two UV filters required, and adjust for exposure factor if not a TTL metered camera ?

I prefer a fingerprint on a filter than on an expensive lens:eek:

Lens hood. Cap when not actually taking photos. Removing the cap when bringing the camera up to shoot soon becomes second nature.

 

I used to shoot rangefinders (film) and only ever forgot to remove the cap a couple of times, not an issue with a SLR.

Use of a protective filter is subject to risk vs benefit considerations. An extra element must have a negative effect on optical performance. On the other hand, it is much easier and safer to clean or replace a filter than a lens element.

 

Filters tend to have a synergistic effect with legacy lenses on digital cameras. Reflections between the flat filter and flat sensor would sometimes produce a veiling flare or bright area in the center of the image. This occurred when a subject was silhouetted against a bright backgound, or there was a bright light just outside the field of vision. I avoided using filters with my Hasselblad for those reasons. However lenses designed specifically for digital cameras have mostly eliminated this effect. Filters now have much better anti-reflective coatings, comparable or better than that found on lens elements.

 

Better safe than sorry, I have installed protective filters on all of my working lenses. I remove them only when shooting against strong backlight.

Can I get away without using one?

I suppose yes? Like most folks here I suggest you should try and experiment. If you have any somehow matching lens and uv filter combo, you should be able to check out if there is a noticable UV filter benefit in your pictures. There are no globally valid answers. I have no clue how your air might look or feel like. I also don't know what you are shooting with. I suppose more recent digital cameras do a better job in filtering UV internally? - Wasn't the D2H on an M8 level bad in that field?

If visible haze is your problem, why do you hope it is just UV light to blame? - I'd supect visible light too and try to shoot (infra) red.

 

Where will things go in the long run for you? I mean a highly coated B+W or even Leica filter in 77mm used for lens protection will get worse over time and belong into the drawer with improvized softener candidates some day. - Are you able or willing to replace those overpriced filters?

In terms of lens protecting investments I recommend getting bags that permitt permanently mounted lens hoods. I still need one for my 70-200.

UV filters do very little to mitigate the effects of blue haze in landscapes. The haze is actually scattering from aerosol particles smaller than the wavelength of light. It is strongly polarized, and reduced greatly with a polarizing filter.

UV filters do very little to mitigate the effects of blue haze in landscapes. The haze is actually scattering from aerosol particles smaller than the wavelength of light. It is strongly polarized, and reduced greatly with a polarizing filter.

 

I never thought to try polarizing filters for blue haze that I'm confronted with in my landscape sessions, sounds like a good trick, must try them out.

It takes, what, 5 seconds to unscrew a filter?

 

That's what I do if I want/need the best image quality. Otherwise, the UV(0) filter is there for grab shots, and to keep dust, condensation, smudges and drizzle off the front element of the lens.

 

Having seen far too many used lenses ruined by over-zealous cleaning, I'd rather wipe dust or smudges off a relatively cheap filter than off the front element of an expensive (or cherished) lens.

 

Having said that. I did have an instance of a flare 'hotspot' appearing in a sunset shot. I took the multicoated UV filter off the lens and the hotspot disappeared completely. Although I have to say it was a one-off occurrence that I haven't seen before or since.

 

BTW, do not get a 'skylight' 1A filter, only a UV0 type. I've never understood why anyone would want to add a slight pink tint to their pictures by using a skylight filter.

I've never understood why anyone would want to add a slight pink tint to their pictures by using a skylight filter.

 

Using Kodak Vericolor II using a1A we found the slight warming useful for outdoor Wedding Portraiture: perhaps I should have been more specific that, it is as a result of what we did years ago that I now have a collection of these filters, which are not now used on my Digital gear.

 

WW

BTW, do not get a 'skylight' 1A filter, only a UV0 type. I've never understood why anyone would want to add a slight pink tint to their pictures by using a skylight filter.

To reduce excess bluishness in outdoor color photographs in open shade under a clear, blue sky, of course. I.e. to remove a slight blue tint from their pictures by using the appropriate correction filter.

^ exactly.

 

Moreover, in addition to being used as "protection" for the lenses, the 1A filters (when we used film), were used becasue our studio shot Weddings in discrete lighting scenario batches and we provided (what is termed here) 5x7 Roll Proofs made for our Client's Viewing.

 

Shooting in lighting scenario batches and nailing a reasonable colour correction using the appropriate Filters for each lighting set, (and we had the weather here to allow most of the Portraiture to be done outside), allowed our studio the economy of making comparative excellent Preview Albums comprising 5"x7" Prints, when competitors were showing Contact Proof Sheets.

 

When we cut over to Digital, it was much easier to create 'discrete lighting batches' in the Digital Post Production process, hence no need for Colour Correction Filters, hence after the sale of the business, I 'inherited' a truckload of 1A Filters of various sizes, all good quality.

 

I believe that the OP is using Digital Gear - so just re-iterating - the initial comment of my owning a lot of 1A Filters was a by the way comment only. I see little use for 1A or 1B Filters with Digital gear.

 

WW

But the Skylight filter has no defined depth of 'pinkness' like anything from the Wratten series. Nikon's 1a filter is not the same as Canon's nor as Hoya's for example. You've only got to put two different makes of Skylight filter side by side on a white surface to see that. And pink isn't the complement of blue, nor is it a CT shift filter colour, that's amber.

 

Using a faintly pink filter on colour negative film? Really? When a twitch of the Y and M printing filters would do the same thing. Totally pointless IME. It's not as if batch-to-batch variations of film or colour paper are within the +/- 0.1R difference that a Skylight filter would make.

Water spray, rain, and dust are the reasons I mount a filter these days. Some fountains leave a mineral deposit that is very difficult to clean off. The lens cap and hood provide good protection for most situations. Post processing eliminates the need for most film era filters.

But the Skylight filter has no defined depth of 'pinkness' like anything from the Wratten series. Nikon's 1a filter is not the same as Canon's nor as Hoya's for example. You've only got to put two different makes of Skylight filter side by side on a white surface to see that. And pink isn't the complement of blue, nor is it a CT shift filter colour, that's amber.

 

Not so. 1A is a Wratten designation, and there is a spectral transmission prescription. If brands differ, it is their mistake to call these filters 1A filters.

It is not a colour temperature correction filter, no. Not strictly blue versus red. But that's not enough to correct real life scene's. Hence the existence of tricolour colour meters.

But it does what i wrote it is made to do.

 

Using a faintly pink filter on colour negative film? Really? When a twitch of the Y and M printing filters would do the same thing. Totally pointless IME. It's not as if batch-to-batch variations of film or colour paper are within the +/- 0.1R difference that a Skylight filter would make.

 

Not so, again. When there is too little red in the recording (either film or digital: same), reducing blue will not add red. It will reduce the overall colour content. However when you filter light in which all colours are present in abundance by using a filter in front of the lens, you can adjust the balance much better.

But true, it is a small correction.

Using a faintly pink filter on colour negative film? Really? When a twitch of the Y and M printing filters would do the same thing. Totally pointless IME. It's not as if batch-to-batch variations of film or colour paper are within the +/- 0.1R difference that a Skylight filter would make.

 

Maybe in your experience, but as mentioned we got actual value from using 1A as I described and this use was at the request of the Lab Tech who printed our Roll Proofs - up to six Weddings per Weekend - so I guess that Lab Tech had some logical reason for requesting the 1A be used and I assume it was to make his printing job easier and not more difficult: I suspect even though it was a little difference it could have been a difference as described by q.g. de bakker.

 

WW

I know the conversation has been shifted past UV filters, but I thought I'd throw this in.

 

A good UV filter, like a Nikon L37c, has a sharp cut-off at 370nm. I've gone through phases of checking filters in a spectrophotometer, and this is a consistent value for filters marked "UV."

 

Good quality optical glass, incidentally, also cuts off at around 370nm. In fact, when doing UV-VIS(or fluorescence) measurements in the lab, the rule I always tell people is to use quartz or polystyrene cuvettes for anything below 400nm. You can get away with glass down to about 380nm, but 400 is a much "cleaner" line to draw. Aside from some cheap glass transmission cuvettes I have a pile of to "loan" to people who I know won't return, my ones for personal use(and loans to trusted people) are quartz fluorescent. They're not a lot more expensive than quality optical glass, but are much more versatile.

 

That aside, I've put my fair share of lenses in the spectrotometer too, and I've never seen one that would transmit below 370nm. Even if there's an exotic material like fluorite(which can transmit down to ~190nm), or a more pedestrian material like plastic, a good part of a typical modern lens is still glass. So, in my mind, a "UV" filter really is just a clear protection filter.

 

BTW, most of my manual focus Nikon lenses that get used regularly wear a Nikon L1Bc all the time. I like the small amount of warmth that it adds to slide film.