The Future Is Here
We may earn a commission from links on this page

The Best Way to Apply Sunscreen to Your Face, Revealed by a UV Camera

We may earn a commission from links on this page.
Applying Sunscreen with a UV Cam
  • Off
  • en

I am a bit of a sunscreen fanatic. My morning and midday sunscreen applications are ritualistic in nature, and I love trying out new products that claim to shield my precious skin from harmful ultraviolet rays. Luckily for me (and unluckily for my wallet), there are a menagerie of sunscreen products on the market these days: sticks, sprays, lotions, powders, and more.

With some of these products, it’s hard to know how—and how much—to apply to get sufficient protection. I decided to try out a few of them using a UV camera on a sunny day in NYC to see with my own eyes what kind of coverage they offer.


The sunscreens

In this video, we tested an SPF 70 sunscreen stick, an SPF 30 mineral makeup powder, an SPF 50 makeup setting spray, a classic SPF 50 lotion, and a lip balm with SPF 30. These broad-spectrum products are designed to prevent UV radiation from penetrating deep into skin and damaging DNA and collagen. Collagen is a protein that keeps skin bouncy and youthful, and when it degrades, we get wrinkles. Much worse than wrinkles is the DNA damage caused by UV radiation—that’s what causes skin cancer.


All of these products, except the mineral powder, are what are commonly called chemical sunscreens, meaning they use ingredients like avobenzone, homosalate, octisalate, and octinoxate to absorb UV rays. When seen through a UV camera, chemical sunscreens appear almost black because they are absorbing the UV rays, stopping the light from bouncing back to the camera lens.

The powder sunscreen contained zinc oxide and titanium dioxide, the two ingredients used in so-called mineral sunscreens. Mineral sunscreens protect us by both absorbing and reflecting UV rays. (Contrary to popular belief, mineral sunscreens mainly work through absorption, not reflection.) An SPF 50 mineral-only lotion appears dark brown in a UV camera because it is absorbing rays while reflecting a small percentage back to the camera lens.

The items we used came from Neutrogena, Supergoop, Physician’s Formula, and Blistex. Since sunscreens sold in the U.S. are all lab-tested and contain basically the same active ingredients, you can be confident you’re getting an effective product as long as you buy from a reputable brand. The American Academy of Dermatology recommends choosing products labeled “broad spectrum” with an SPF 30 or greater.

The UV camera

To make this video, we used a Nikon camera that was modified with a special UV filter to capture UV rays while filtering out visible light. Ultraviolet light has a shorter wavelength than visible light, making it undetectable to our eyeballs. But that shorter wavelength is what makes UV so effective at penetrating skin.


This camera only shows one kind of UV radiation—there are three!—called UVA rays, which travel into the deeper layers of skin. UVB rays, by contrast, are the ones primarily responsible for sunburns. The third type, called UVC, is thankfully filtered out by Earth’s atmosphere.

The results

I was blown away when I first applied the stick and lotion sunscreens while watching the coverage capture by the UV camera. Though the products appeared clear on my skin, in the UV camera monitor, it looked as though I had just rubbed dark paint on myself.


I thought it was fun to spritz on the setting spray, which is designed to be applied on top of makeup. But the UV camera revealed that I had achieved only spotty coverage. Ideally, I would have applied a lot more spray and rubbed it in to ensure even protection. It was also a breezy day, and I know I lost a lot of the product in the wind.

The mineral powder was very disappointing. I’ve always been skeptical of using SPF-boosted makeup products because most dermatologists say you can’t trust them as your primary sun protection. This test validated my skepticism. You could see a very slight darkening where I applied the powder in the UV camera monitor, signifying some UV blockage, but it was very subtle, meaning the powder was providing inadequate protection. I might use a powder to touch up a base layer of lotion sunscreen, but I definitely wouldn’t rely on SPF powder alone.


The SPF 30 lip balm was really nice: With only a brief swipe over my lips, it appeared to the UV camera as though I had put on black lipstick. Don’t forget to protect your lips—they can get sunburned, too.

So there you have it: To get the best protection, at least according to our test, use a broad-spectrum SPF 30 or higher lotion as a base. Powders and setting sprays can give you some minimal protection, but don’t rely on them alone. And remember to protect your lips with a lip balm boosted with at least 30 SPF.


Protecting yourself from the Sun is extremely important—about 9,000 people die from melanoma in the U.S. every year, and the American Cancer Society estimates that over 90,000 new cases of melanoma will be diagnosed in the U.S. this year.

And remember, you need to apply sunscreen year round. While UV rays are more intense during the summer months, they can still damage your skin in the winter.


After seeing how effectively lotion sunscreen absorbed UV rays in this test, I feel a lot less guilty about all the money I’ve spent on sunscreens over the years. But I also noticed that I tend to miss spots, like my ears and around my eyes, which is why wearing hats and sunglasses and seeking shade are equally important sun-protection strategies.