Full Frame or Crop Sensor

What’s the difference between a full frame and crop sensor camera? It can be very confusing when you’re starting out and looking for the ‘right’ camera for you.

The differences are technical differences, which in some circumstances can become creative ones. Yes I know that statement is confusing. Both have benefits so it’s a case of matching your needs to one or the other. .

There are so many different sensor sizes I’m not going into the maths of them all here. I’m only going to explain the main differences between full frame and crop sensor cameras and how they affect you creatively which will help ypu make an informed choice.

Full Frame sensor means the sensor is the same size and shape as one frame of 35mm film. The light projected onto it fits it perfectly so the focal length of the lens is what it says it is. 24mm - 50mm - 200mm etc.

A crop sensor is a smaller sensor so the area of light projected by the lens is bigger than the sensor area, so you only capture from the middle of the lens’s projected image. This has the effect of making a 50mm lens appear to have the magnification of a 65mm, 75mm, 80mm or even 100mm lens depending on the size of the sensor.

This means crop sensor cameras make the lens appear to be longer. They make things further away come closer than a FF camera using the same focal length lens because they 'crop' from the middle of what the lens is projecting onto the camera's sensor. So it appears to add a bit to the length.

Crop sensor cameras also have slightly more depth of field than a full frame.

The downside is they have fewer pixels so you lose resolution if you crop in post production. At high ISOs they generally have more grain than a full frame camera. However I have a Fuji XT-1 CSC camera which has a crop sensor and can shoot 2000 ISO or more with completely acceptable image. I can only conclude ISO performance is improving for this type of camera.

The full frame camera makes the lens seem a little shorter and there is a little less depth of field so backgrounds become more blurry.

The benefit is you have more pixels to crop into and therefore can maintain higher resolution (have more pixels left) after you have cropped. The high ISO performance and image quality is generally much better all round.

As with everything in photography there are costs and payoffs to both.

Full Frame Benefits:

Very very high image resolution so you can crop or reproduce the image files as big prints a full frame
Great for softer shallow death of field blurry backgrounds (especially when combined with a wide aperture f2.8 lens)
Generally better high ISO performance so good in low light or if you need to use very fast shutter speeds.
Short focal lengths appear shorter (wider angle)

Crop Sensor Benefits:

Still high image resolution - but not as much as a FF
Great for landscapes because there’s slightly more depth of field available
Lenses appear to have more magnification (seem longer)
ISO is good (and getting better) but at the time of writing this, not as good as a FF

When choosing ask yourself questions like...

Do I need more image resolution for enlargement or cropping?
Do I want more front to back sharpness - or more blurry backgrounds?
Do I want better low light performance - or do I mostly shoot in fair to bright conditions?

Creatively the differences are small so it’s up to you to choose what is most important to you, the type of photography you like most and what you’re going to do with the image files afterwards.

Remember, it’s not the camera that takes the image, it’s the person using it. It’s down to the photographer’s skill with light, composition and how they think their shots through that makes for exciting imagery.