To filter or not to filter. It's an age-old question that has no correct answer. There are two main opinions to this question. The first is to never use a UV filter. Why put a cheap piece of glass in front of your expensive lens? The second is ALWAYS use a UV filter! It's much cheaper to replace a scratched or cracked UV filter than the front lens element of your lens.
I can't tell you which side is objectively better, but what I did do is pit our favorite UV lens filters against each other in some calculated optics tests. I will leave it up to you to determine if the trade-offs are worth it.
So What Does A UV Filter Do?
UV lens filters are designed to cut through the effects of UV rays or atmospheric haze. Although most options look like any old clear filter, they range in cost and you get what you pay for. Some cheap filter options will actually do the reverse of what they were designed to do, being more susceptible to lens flare. Of course, if you are shooting directly into the sun, using a lens hood is always a good option.
Like we've mentioned before, adding a UV filter for protection just provides peace of mind. We can't tell you how many times we've had customers come in with a "broken lens" to find out they have only shattered the filter and it's saved them hundreds if not thousands of dollars. It's also a great layer of protection from dust, moisture, or dirt that could potentially scratch your lens element. Needless to say, it's important to do your research and find the best UV filter for your needs.
We decided to help you along in the research process and test UV filters from our top three filter brands: Breakthrough photography, Hoya and Promaster. Specifically, we tested the Breakthrough X2 and X4 UV, Hoya NXT Plus UV, and Promaster HGX II UV.
Before we get started, there are a few things you should consider when purchasing a filter. First, you will want to know what type of glass the filter is made from; better glass means better image quality. The second is how many coatings the filter has. These coatings help with the color transmission for less glare, flare, and ghosting.
Camera Lens Filter stats:Breakthrough X2
- Japanese AGC glass
- 8 coatings
- German SCHOTT B270 glass
- 16 coatings
Hoya NXT Plus
- German SCHOTT B270 glass
- 10 coatings
Promaster HGX II
- CORNING Optical UV cut glass
- 32 coatings
UV Lens Filter Tests
To start, we put these filters in the absolute worst situation they can be in to see how they affected image quality. I wanted the test to be the same for all the filters so we opted for some video lights. We lit a Calibrite Color Checker from the front and then placed a second light behind pointed directly at the filter to simulate a backlit situation. Click to enlarge these five images without labels and decide for yourself what one looks the best.
Think there is a clear winner? Here are the filters used in each shot. 1) Hoya NXT Plus 2) Breakthrough X2 3) No filter 4) HGX II 5) Breakthrough X4
Here are some zoomed-in images so you can see how each filter affects contrast and color, if at all.
Next up, we removed the light pointed at the filter and lit the Calibrite normally. Here are the zoomed-in versions of these images because I think you will be hard-pressed to notice any image quality loss.
Lens Protection vs Image Quality
Now, here is a short opinion on using filters. Can they affect image quality? Yes. Do they provide lens protection? Yes. Whether you will be using it as a protective filter or to help eliminate ultraviolet rays, the question you need to ask yourself is what will work best for you.
Personally, we recommend meeting somewhere in the middle. Keep a filter on your lens until you know you may be putting it in a situation where it might cause image quality loss. Then take it off if you are shooting backlit portraits as the sun is going down because you are most likely to get some flaring. Once the shoot is over, put your filter back on. Whoever said you can't have your cake and eat it too didn't try hard enough.
If you're interested in learning more about filters, in particular neutral density filters, stay tuned for Part 2.