Human eye

What Is a Telephoto Lens?

Telephoto lenses can be incredibly useful, but how is it different from other lenses, and when should you use it?

What Is a Telephoto Lens?

A telephoto lens is a lens that appears to magnify distant objects. To do that, they need to have a focal length longer than that of a normal lens, or a lens that approximates the optical qualities of the human eye. A normal lens has a focal length of between 40mm and 58mm on a full frame camera so any lens with a focal length longer than 60mm can be considered a telephoto lens. The longer the focal length, the more magnification there is.

The most common telephoto zoom lenses have a focal range of 70mm to 200mm. Any lens with a focal length longer than about 300mm can be considered a super telephoto lens as well.

On a crop sensor camera, telephoto lenses are those with a focal length longer than about 40mm, although the magnification will be minimal until about 50mm.

Let’s look at this in action. This photo was taken at 50mm, a normal focal length, on a full frame camera. The photo appears pretty similar to how things look with your eyes. The other photos were all taken from the same spot with a crop sensor camera; I don’t have a long enough full frame telephoto to really make the point clear.

This photo was taken at 45mm using a crop sensor camera. The full frame equivalent focal length is 72mm. You can see how the image is a little tighter on the car.

This photo was taken at 85mm, equivalent to 136mm on a full frame camera. Now the car totally fills the frame.

This photo was taken at 135, equivalent to 216mm on a full frame camera. We’re incredibly close to the car compared to the normal photo. It’s impossible to fit the whole thing in the picture.

How a Telephoto Lens Affects Your Images

The main effect of telephoto lenses is that, like a…

What Is a Wide Angle Lens?

A wide-angle camera lens can make for some pretty interesting photos, but how is it different from other lenses, and when should you use it?

What Is a Wide-Angle Lens?

A wide-angle lens has a field of view significantly wider than that of the human eye. In other words, it’s got a wider field of view than a normal lens, which has a focal length of somewhere between 40mm and 58mm on a full frame camera.

This means that, on a full frame camera, any lens with a focal length of less than 35mm is considered to be a wide-angle lens. The lower the focal length, the wider the field of view and thus, the wider the lens. Any lens with a focal length lower than 24mm may be referred to as an ultra wide-angle lens.

On a crop sensor camera, wide-angle lenses start at a focal length of around 24mm and go down from there. Ultra wide-angle lenses start at around 16mm.

Let’s look at this in action. This photo was taken at 50mm, a normal focal length, on a full frame camera. The photo appears pretty similar to how things look with your eyes.

This photo was taken at 35mm. It just qualifies as wide-angle. Notice how much more of the scene is showing.

This photo was taken at 24mm. This is the start of “ultra” wide-angle. Once again, even more of the scene is captured in the photograph.

This photo was taken at 17mm, which is as wide as my lens will go. The image looks completely different than the one taken with the normal lens.

How a Wide-Angle Lens Affects Your Images

The most obvious effect of wide-angle lenses is their massive field of view. You can just capture a huge…

How Does the “8x” Zoom on My Point-and-Shoot Compare to My DSLR?

Your camera may boast “8x zoom”, but most DSLRs do not advertise values like these. So how do they compare? The answer is more complex than you may think.

That “8x” value that doesn’t necessarily mean objects in the photo will look 8 times bigger than they do with your eyes. It just means things will be 8 times bigger than its most zoomed-out position—but two cameras in their most zoomed-out positions will not look the same size.

Every lens affects your image in a different way. A wide angle lens warps the perspective in the image so it shows more than you could see with your naked eye. A telephoto lens does the opposite, zooming in like a telescope to distant objects. These things are separate from the actual “zoom” function on your camera, so one 8x zoom lens may not make objects as large as another 8x zoom lens.

So how do we calculate how much bigger an object appears in a photo compared to your eyes, where you’re currently standing? To find that out, you need to know the focal length and field of view of the lens you’re using.

“Canon vs Nikon:”
Did you know about this one camera setting that ruins your pictures? Go to uglyhedgehog.com

Focal Length and Field of View

In photography, the focal length of a lens is the distance between a the camera’s sensor and the internal components of the lens itself. This focal length determines how close objects look to your camera and what part of the scene actually fits within the picture—otherwise known as your field of view. A massive, telescope-like lens with a 1000mm focal length will make objects look very close. Lenses with smaller focal lengths will make objects appear farther away.

Many lenses can “zoom” to different focal lengths. For example, an 18-135mm lens will let you zoom from an 18mm focal length to a 135mm focal length.

Here’s an example. I shot the following two images with my Canon 650D and an 18-135mm lens.

The first photo was taken at the shortest focal length: 18mm. It’s a pretty wide field of view.

The next photo was taken in the exact same place half a second later. The only difference is that I’ve zoomed in to use the lens’ longest focal length, 135mm.

As you can see, the field of view is a lot narrower in the second photo than the first, because we’ve zoomed in on the mountains.

Here’s the catch, though. Different lenses, at their shortest focal length, will show things differently. Remember that 1000mm telescope lens? Even if you don’t zoom in with it, you’re still seeing things much closer than a camera with an 18-135mm lens. So focal length alone isn’t…