Photographers hear about sensor size all the time, especially when looking to buy a new camera. These include APS-C, Four Thirds, 1″, and of course full-frame, the benchmark format against which all others are compared. But what is a full frame camera and does it make a difference?
In this article, we’ll explain the basics of what a full-frame camera is in photography and whether you should consider buying one as your next camera.
What is a full frame camera
Simply put, a full frame camera has an image sensor that is exactly the same size as a full frame of 35mm film. With an aspect ratio of 3:2, the sensor is 36mm × 24mm in size and the sensor captures the exact field of view as if the camera contained a roll of 35mm film. Except it’s digital.
This contrasts with APS-C (Advanced Photo System type-C), which is a sensor size roughly equivalent to format C (or “Classic”) Advanced Photo System film negative. This format is equivalent to the Super 35mm motion picture film format, which also uses standard 35mm film but records images vertically on the film rather than horizontally like a 35mm camera.
A photo frame recorded horizontally by a still camera on 35mm film is 24×36mm, while a frame recorded vertically by a motion picture camera is about 1.4 to 1.6 times smaller, which you may recognize as the crop factor of APS-C image sensors.
Advantages of full-frame cameras
According to Kodak, a complete frame of 35mm film has an effective resolution of 6K. And while full-frame cameras have been around for nearly a decade, it’s only recently that image sensors have been able to achieve the same physical resolution as film. Despite the long development time, however, the sensors now exceed the quality of the resolution, which makes the basic comparison with the film somewhat outdated.
With more pixel site space on its larger surface, full-frame sensors generally offer higher resolution than crop sensors.
Wider field of vision
A lens will have a wider angle of view on a full frame camera than on a crop sensor camera. Photographers working in certain genres such as landscape photography and real estate photography can benefit from their lenses capturing more of a given scene.
Better in the extremes
The advantages of a full-frame sensor over other sensor sizes are pretty obvious. It’s bigger. The larger the sensor, the more light it can collect and with much less noise. It’s not about the image resolution, mind you. There are 4K APS-C sensors and full-frame 4K sensors. But the difference is in the noise level, especially in low light. As they generally have larger pixel sites, full-frame sensors are generally superior at capturing higher quality and less noisy photos in low-light environments.
As a result, a full-frame sensor, while larger than APS-C or Micro 4/3s, offers better low-light performance and a sharper image.
Full-frame cameras also benefit from greater dynamic range, providing much more detail in extremes of light and dark. Deeper blacks and more detail in high exposure areas. This translates to the ability to take higher contrast images or, when an image is overexposed or underexposed, to be more likely to save an image with post-processing due to that extra dynamic range. There will be greater latitude to recover blown highlights or deeper shadows in a similar image captured with a cropped image sensor.
“More bokeh” (a little)
Another benefit of a full frame camera is its ability to capture “more bokeh” than a crop sensor camera. While the same focal length and lens aperture will result in the same depth of field on both full-frame and APS-C cameras when shooting a subject at the exact same distance, the angle of view (and therefore composition) will be different.
To achieve the same full-frame composition with the same lens, a photographer using an APS-C camera would need to move away from the subject. And the further the camera is from the subject, the deeper the depth of field (and the less bokeh you get).
In other words, a photographer switching to a full-frame camera from a crop sensor will find that their lens collection suddenly seems to capture more bokeh when framing subjects in exactly the same way, even though that results from the different cameras. the distance to the subject and not the sensor itself.
Disadvantages of full-frame cameras
With better resolution, less noise, better low-light performance, and blurrier bokeh, it would seem like choosing a full-frame camera is a no-brainer for a photographer. Well, wait. The are some compromises with full frame versus crop.
Height and weight
First, at least when it comes to DSLRs, cameras are generally heavier and bulkier than their crop-sensor cousins. This is rapidly changing with the popularity of mirrorless cameras, which are rapidly replacing single-lens reflex (SLR) cameras. But face to face, a full frame camera will be bigger and heavier than an APS-C or Micro 4/3s camera. And APS-C mirrorless cameras now offer increased portability over their full-frame siblings.
Fewer compatible lenses
Full-frame cameras also cannot accept cropped sensor lenses without an adapter, while crop-sensor cameras can use both full-frame and crop-sensor lenses. In a DSLR with a mirror shutter, it has to do with the “flange distance”, or the distance between the end of the lens and the sensor. The lens only interferes with the mirror, so an adapter is needed.
Even when it’s an adapter, the image circle is also vignetting on the full-frame sensor, so a smaller lens can’t capture the whole image like a full-frame lens. The end result is having to crop in some way to avoid the black letterbox that surrounds the photo.
Full frame cameras are also generally more expensive than crop cameras. Obviously, when it comes to larger sensor size and a smaller customer base of more serious photographers, the result is to produce fewer sensors in a single production run, which translates to costs. However, the old adage “you get what you pay for” comes into play. And if one prefers to opt for a full-frame sensor, the investment definitely pays off.
The best full-frame lenses are also generally more expensive (and higher quality) than lenses designed specifically for crop sensors.
The higher resolution of full-frame sensors comes with larger file sizes. Photographers will have to deal with the increased storage load of larger images, so the cost spent on things like backup drives and cloud services will likely be higher than when shooting smaller images from a crop sensor camera.
Do you need a full frame camera? Well, in the beginning, full frame definitely had advantages. Even today, they have advantages, especially for professionals. But even professionals are starting to see the performance curve flatten between full-frame and its smaller-sensor counterparts. Going for a more mobile rig with smaller lenses is a luxury that many shooters can afford, as image sensors have higher resolution, and post-processing and computational photography at least mitigate some shortcomings of a smaller sensor.
The bottom line comes down to preference and style of photography. A sports photographer may want a lighter and more mobile rig, especially when dealing with longer focal length lenses. Meanwhile, a portrait photographer may want the added control over depth of field that a full-frame camera offers because there isn’t much movement with the camera. Then there’s a fashion photographer who may want the best of both worlds.
It all depends on what works best for you and your particular photography niche.