Every photographer is probably familiar with protective filters. They are often recommended when purchasing a camera or lens. But when are they really necessary? How to use them correctly? Let’s find out.
What is a lens protector and how does it differ from a UV filter?
From the name it is clear that such filters are supposed to protect the front lens from damage. Today under the protective filters are understood two classes of filters: protective and ultraviolet. Simple protective filters can be labeled Protect, Clear, Neutral and other variations, while UV filters are clearly marked UV.
What is the difference between a protective and UV light filter? A protective filter has almost no effect on the light that passes through it, including the rays of the ultraviolet spectrum, while the UV filter blocks the rays of these wavelengths. Note, however, that the digital camera matrix already has a UV filter, so there is no visible effect of an additional UV-filter, its function is also limited to protecting the front lens from damage.
If you don’t just want to protect the lens, but also get effects (say, increase contrast or remove haze when shooting a landscape), get polarizing filters, which in many scenes can improve your pictures.
Negative effects of using a protective filter
Any glass placed on a lens becomes part of its optical circuitry. Even the best protective filter will have a negative effect on the quality of your images due to additional glare, over-reflections, loss of detail and some light.
Photographers often shoot with harsh sidelight or backlighting (e.g. sunrise, sunset scenes). At this point, any light filter will noticeably catch glare. To reveal the full potential of your technique, let the powerful anti-reflective coating of modern lenses work properly, you should shoot without protective or UV-filters.
Is it a mistake to always wear a lens protector?
Sometimes photographers, after buying a protective filter, immediately put it on the lens and don’t take pictures. This is a mistake. First of all, the quality of the photos decreases – the sharpness falls, there are a lot of ghost shots. Secondly, sometimes a permanently installed light filter just “gets stuck” to the lens barrel, and such issue can only be solved in a service center.
The front lens itself of modern lenses is not so delicate. Often manufacturers put protective compositions on it. They help avoid glare and chromatic aberrations. Lenses are also coated with a strong protective fluoride coating. It helps prevent splatter and fingerprints from rolling off your lenses. And to leave a scratch on the lens, you either have to do it on purpose, or be extremely careless with your equipment. If you use your lens with care and do not carry it without a cap in your purse along with your keys, it will hardly need additional protection.
Some lens protectors (especially those with thin frames) don’t hold the lens cap well. It may come off the lens right in the case and damage the protector with its hard ribs. The latter, unable to withstand the pressure of the lens cap, may burst and scratch the front lens lens.
But even if you want to wear a lens protector all the time, you have to take it off while using other filters: polarizing, neutral-gray. Firstly, a “sandwich” of filters will reduce photo quality even more. Secondly, with wide angle lenses the rims of filters will be caught in the frame, making darkening and vignetting at the edges of the picture. Also you should remove the protector in case of taking pictures with a hard side or back light, in the evening city, to avoid glare.
When do I need a light filter?
You don’t wear a light filter on your lens all the time. It is installed when there is a real danger of damaging the front lens. For example, if you are shooting a sea storm or a rough waterfall, reportage from an off-road race or shooting sociable animals that try to lick your lens – are also reasons to install a lens protector.
How to choose a safety filter?
It is important to determine the economic feasibility of such a purchase. It makes no sense to buy an expensive light filter to protect a budget lens. At the same time, an inexpensive light filter will greatly reduce image quality and there is no point in it either.
If a lens protector is still needed, decide on the appropriate filter thread diameter. It is specified in the characteristics of the lens and on the back side of the lens cap.
It is important that the filter has an anti-reflective, antireflective coating. A simple piece of glass without such a coating will strongly catch glare and reduce image contrast. As a rule, “antireflective” filters are labeled MC (MultiCoated). Different manufacturers may have brand names: e.g. DHG, MRC or HMC. The most affordable light filters are not made of glass but of plastic and are not worth buying.
If you are going to use light filter on super wide angle optics, choose filter with thin frame. This will keep you from blurring in the corners of the frame. A disadvantage of thin frames is that the lens cap loosely adheres to them.
To sum it up
- Protectors and UV filters do not improve the quality of photos and often cause loss of sharpness, contrast, and unwanted glare.
- UV and protective filters do not have any artistic effect on the digital frame. If you need effects, consider polarizing filters, for example.
- Protective and UV filters should not be worn on the lens all the time, only when necessary.
- You must remove the filter before you mount other types of filters, because the more filters there are, the lower the quality of the picture.
- Make sure that the filter has an anti-reflective multi-layer coating.
- The most vulnerable parts of the lens are the rear lens and the “trunk”, which move out when zooming or focusing. A light filter will not protect them in any way.
- And the last thing – you will not be able to use a lens with perfectly preserved front lens, but with its body broken. And you won’t be able to sell it on the secondary market for a good price. Therefore, it is better not to rely on protective filters that give false confidence in the optics protection, but to develop the habit of careful and careful attitude towards the equipment. For the same reason, you should choose a good photo bag or backpack to safely carry your equipment.