Introduction
Having a DSLR Canon camera means you are serious about photography. If you want to become even more serious about the type of photos you create, you’ll need to know about the style of Canon lenses available and how they give you different results depending on the kind of camera you have.
Table of Contents
The Definition of Full Frame and APS-C
Before we start looking at the two types of lenses, it’s essential to understand the difference between full-frame and APS-C cameras. A Canon DSLR camera will either have a full-frame sensor or the type called APS-C. The main difference between these sensors is their size. For those who have used film cameras, you may recall the size of the 35 mm negative produced when the film was processed. The size of each negative frame (36 mm x 24 mm) is the same size and shape as a full-frame sensor, which is a friendly correspondence.
If you don’t have a full-frame DSLR, you probably have one with a sensor that is the same size and shape as another type of negative—this time, it’s from the Advanced Photo System. This image sensor is called a crop sensor, and it is similar in size to the Advanced Photo System negative in its C (Classic) format, which is 25.1×16.7 mm.
A full-frame sensor has the advantage of a large number of pixels available to capture lots of detail. It also has bigger pixels, so it doesn’t need to use high ISO to get photos in low light, adding another level of fine detail to the image you’re taking.
If you use the same lens on a full-frame camera and a crop sensor device, you will notice one significant difference when you look through the viewfinder. Because the APS-C sensor is smaller than the one in full-frame cameras, there is less area to capture the scene, and you’ll see a smaller size compared to having the same lens on a full-frame camera. This is known as the crop factor. It makes it look as though you’ve zoomed in on the view.
Full frame cameras are designed for the professional end of the market, while APS-C cameras are made for hobbyist photographers and beginners.
Understanding Lens Mounts
Canon’s two lenses (EF and EF-S) use bayonet bases to attach themselves to the lens mount. The EF can be fixed to a full-frame Canon DSLR and work on a Canon DSLR camera with a cropped APS-C sensor. But the EF-S lens will only fit the Canon APS-C DSLR.
What is a Lens Mount? Rather than switching cameras whenever they want to try a different photo style, DSLR users can change lenses on their camera’s body instead. To do this, they press a button on the camera’s face and swivel the lens to disengage it. Then they grab a different lens and attach it to the lens mount on the camera. This lens mount is the area that securely locks the lens onto the body of the camera.
The lens mount provides electronic communication between the lens and the camera for the autofocus and exposure systems. Because the lens mount has an array of electrical contacts that ‘talk’ to the contacts on the lens base, you can’t take lenses from different manufacturers and expect them to work on another brand’s device. With the constant changes in technology, even lenses made by the same manufacturer may not fit your existing equipment.
A History of EF Lens Mounts If you see the letters’ EF’ on your lens, it stands for ‘Electro Focus,’ which means an electronic autofocus motor is in the lens. Back in 1987, Canon designed this autofocus system for single-lens reflex cameras. This innovative feature had focusing motors within the lens itself. Before this, Canon had the focusing motor in the body of the camera and it was mechanically connected to the lens. To make this new method of autofocusing work, Canon created a bayonet-style EF lens mount with no mechanical linkages between the lens and the camera’s body.
One of the reasons for changing the mount’s style was to use an electronic interface between the lens and the body. The larger diameter of the EF mount enabled Canon to position the lens further from the film plane, which made it easier for them to design a new set of lenses. And the larger lens mount gave more space for the electrical contacts that communicated between the body of the camera and the autofocus motor within the lens.
Linking the camera with the lens via electrical impulses gave this lens a high-speed autofocus system. The development of having the autofocus system within the lens was an advantage because the autofocus motor could be tailored to the requirements of each lens. A telephoto lens could have a larger, more appropriate motor, and a smaller lens could use a more compact motor. The next stage of development was the introduction of the EF-S lenses in 2003. These were made specifically for Canon’s APS-C cameras.
EF Vs EF-S Lenses Camera equipment isn’t cheap, but it’s false economy to buy a cheap lens if you need perfect sharpness and clarity. If you purchase a Canon EF lens you will have a quality product that fits a Canon full-frame camera and it can be used on a crop sensor camera too. EF lenses have a distinct advantage over EF-S lenses because of their status amongst camera enthusiasts. If you decide to change to a Nikon or perhaps a mirrorless camera, you will need a new set of lenses, and selling EF glass is easier than those marked EF-S. The EF lenses hold their value a bit better than EF-S lenses.
Can I Use EF Lenses on Crop Sensor Cameras?
EF lenses are designed for Canon’s full-frame cameras, but they will fit on Canon’s crop sensor (APS-C) devices too. Everything, including autofocusing, will work perfectly. Since the crop factor of a Canon APS-C sensor is 1.6x, it means the EF lens will behave as if it’s 1.6 times longer than its listed length. This is great if you want it to act as a telephoto lens because, for example, a standard 50 mm lens on a crop sensor gives you the same as an 80 mm lens. This is an advantage if you are a wildlife photographer, as your 300 mm lens will provide you with the equivalent of a 480 mm field of view, making your subject even closer to the viewfinder.
Benefits of EF Lenses The main advantage between Canon EF and EF-S lenses is that they are known for their better build quality. Since they are aimed at the professional user, they are made from solid components and can handle everyday use. You can use Canon EF lenses on their full-frame and APS-C cameras. If you attach an EF lens to a crop sensor camera, it gives you extended reach, handy for sport and animal photography.
Drawbacks of EF Lenses EF lenses are rugged and dependable, but that comes with a physical and financial cost. These lenses are solidly made, which means they are bigger and heavier than EF-S lenses. And you’ll have to dig deeper into your pockets if you want one of these lenses, as they are made for serious photographers who don’t mind paying for quality results.
Can I Use EF-S Lenses on Full-Frame Cameras?
Canon EF-S lenses are only designed for crop sensor (APS-C) cameras. EF lenses project a large circular image onto the sensor, and if the sensor is smaller than the image circle (as in the APS-C) sensor, it makes for a cropped field of view. But going the other way produces two problems. The main issue is that it won’t fit on the lens mount of a full-frame camera. If it did, the optical elements of the lens would go too far into the camera body and would damage the mirror. And if you make it fit the mount via an adapter, the small image circle produced by the EF-S lens is not big enough to cover the large sensor in a full-frame camera, and you end up with vignetting.
Benefits of EF-S Lenses Since the inside of a Canon APS-C camera only has a little mirror, it allows the optical elements of an EF-S lens to extend deeper into the camera’s body to get closer to the sensor. This short back focal length means these lenses can be made with less glass, making them smaller, lighter, and cheaper than the EF range. Despite their budget price, they still produce excellent results. The compact size of the EF-S lens makes it ideal for travel photographers who appreciate carrying less weight around all day and for street photographers who want to be less noticeable while shooting in crowded environments.
Drawbacks of EF-S Lenses The main disadvantage of having the EF-S style of lens is that if you decide to upgrade to a full-frame camera, you’ll have to buy a whole new set of lenses as well. Being budget lenses, you also won’t find ‘fast’ lenses in this range. The glass elements in the EF-S lenses are not up to the same standard as Canon’s L series, so you won’t find a lens that shoots at less than f/2.8 aperture. And if you like doing wide views of landscapes and seascapes, you’re going to have to overcome the cropping of the sensor by purchasing an extensive lens. A 10-22 mm lens will only look like a 16-35 mm lens on a Canon APS-C camera. Extreme wide-angle lenses are much more expensive than standard ones. They require more glass to get the extra range of view. When you add the cost of the different glass to the price of the technology needed to overcome distortion, you end up with a costly lens.
Which Lens is Best for a beginner?
Both lenses are good value, but that’s relative to their price tags. If you use an APS-C camera you can choose the high-quality EF lenses or the budget range of EF-S lenses. If you are a beginner with a full-frame camera body you don’t have much choice, you have to stick with Canon EF lenses. EF lenses have fantastic quality, but they cost more than the Canon EF-S lenses.
Canon’s APS-C cameras combined with EF-S lenses are ideal for a wide variety of photographic activities, from action shots to landscapes. And because of their crop sensors, they are instrumental in telephoto situations such as bird and wildlife photography. Beginners will also appreciate the small size and lightness of EF-S lenses, making them ideal for long days of travel photography.
If you are a real estate photographer or landscape photographer who wants the actual effect of a wide-angle lens, you have to use a wide-angle EF lens on a full-frame camera.
Which lens is best? In the battle of Canon EF vs EF-S lenses, it all comes down to what you need it for and how much you are willing to spend.
