To UV or Not to UV - That is the question!
/
IF YOU MUST USE A UV/PROTECTOR SPEND THE MONEY ON A GOOD PRODUCT LIKE THIS B+W NANO COAT
Hello neighbours! I wanted to address a question that comes into me fairly regularly and it pertains to the use and need for UV or protective filters. It’s a recurring question as folks buying new cameras and new lenses get the full court press to buy a filter, so let’s figure out if this is necessary.
Lens Construction
Modern camera lenses today are excellent. The optics are capable of more resolution that you can see on any display or any print, unless of course you zoom in 5x lifesize and press your nose against the display or print. I know folks do this. It’s a pointless waste of time.
So you can conclude that the manufacturer has done their due diligence in producing an optic that is capable of making sharp images with excellent tonal balance and contrast transmission. The individual lens elements are ground from optical glass. There are not many makers of optical glass in the world. Sony acquired Minolta’s glass factory. Nikon has always made their own glass. Zeiss is a glass maker and so are Schott and Schneider. Other camera makers will buy optical glass blanks from an optical glass provider and then grind their own elements. This is all excellent news, and you should expect nothing less than optical glass in any lens worth using.
They do this with an arrangement of individual lenses that are curved, polished and coated to reduce internal reflection and to minimize loss of sharpness or contrast by refraction which happens whenever light changes medium, such as from air to glass or vice versa.
All are important but one of these functions, multi-coating, is frequently misrepresented in camera stores and certainly in uninformed big box sellers.
The front element multi-coating on any lens from a major camera manufacturer is tough. It does much more than just make corrections, it’s also hardened to protect that front element and contains chemistry to repel the nasty stuff. It’s actually tougher than the glass it is coated to. Note we are speaking of multicoating in the last thirty years. Much older lenses will have less sophisticated coatings which may not have the same level of hardness, however the majority of photographers aren’t using old lenses.
Filter Construction
Filters were initially created to alter the incoming light to deliver alternative final results on film. Different films responded differently to different types of light, and the colour temperature of the source light was an important consideration for serious photographers. Those early filters from lens makers such as Minolta, Nikon, and Zeiss as well as the filters from companies specializing in optical grade glass filters were and remain superb at their tasks. However, with digital photography, colour balance has no relevance when shooting in RAW so these corrective filters are no longer required.
One of those filters was the UV or Ultraviolet filter. The concept and deliverable of a high quality UV filter such as Nikon’s L37 for example, was to filter out UV light which did (and does) have an impact on the film emulsion. Lenses did not have UV blocking technology in their designs as a matter of course for many good reasons, and adding an optically precise UV filter for film was a logical step. However, those filters were never inexpensive.
Along came the aftermarket offering inexpensive filters made from generic glass that was frequently uneven, contained dirt, and was not built with optical precision in mind. In my life, I have probably removed over a hundred of these cheap pieces of junk from client lenses, because they cross threaded, or welded themselves in place. They were junk then and are junk now. Often many of the so-called UV filters didn’t even do any UV filtration. We call that lying.
As digital replaced film, folks figured out that sensors already defined what wavelengths that they would receive and the need for a UV filter in any way ceased to exist. One may not do any harm, but it sure won’t do any good either. So the makers renamed them Protection Filters. In the vast majority, this is another big lie. Most are made of cheap non-optically correct glass, have no multi-coating and are 10x more fragile than the lens front element. If one breaks, the sharp edges of the glass could in fact do more damage than something bouncing off the front element directly. They provide less protection than the lens front element does. The mounting rings are typically made of forged aluminum, not milled from billet and so are irregular, and readily deformed. They also tend to be quite deep, which causes vignetting on wider angle of view lenses. They are perfect if you want something stuck to the front of your lens that only distorts the image, and increases the indices of reflection and causes more refraction.
These filters are of no practical use whatsoever…
Some photographers will choose to put a protective filter on the front of their lens if they are photographing in a hostile location, such as excessive fine sand, salt water, or a dirty location, such as a rodeo where my presence guarantees rain and mud. This is ok, if and only if, the protective filter is made of optically correct glass and is multi-coated from a respected glass or lens maker. If that sounds to you like expensive, you are absolutely correct. The filter does nothing to improve the image, only offer minor to questionable protection.
Can I Buy High Quality Protection Filters?
Yes you can. I recommend B+W MRC Protection Filters with the thin rings the are made from Schneider glass or the thin ring Heliopan line that are made from Schott glass.
Why The Full Court Press?
I once worked in photographic equipment sales. Filters were always a pushed item, because the cheap stuff had enormous margin, compared to brand name lenses or brand name filters and also came with a sales incentive in the form of a payment for selling called a SPIFF. The stores made more money on cheap filters than on similarly priced gear from a major manufacturer. Sales people, who are typically paid at minimum wage, live by the SPIFF list to earn extra income. That’s reality. The uninformed actually believe the protective / UV filters tripe and the more seasoned know the truth but still need to eat. If you are buying a lens and the seller insists that you buy a filter, say no. If they persist, leave and buy your lens somewhere else.
For the vast majority, the protective / UV filter “need” is a complete fairy story. Be informed and know better.
Thank you as always for reading. If you shop with B&H Photo Video, please do so through the link on the home page. It costs you nothing and we earn a small commission on anything that you buy through our link. To be notified of new articles subscribe. Please also subscribe to the audio podcast for more trusted information. Until next time, peace.
