When you're shopping for a camera, sensor size is one of the most important specs to understand — yet it's also one of the most confusing. Terms like "full frame", "APS-C", and "Micro Four Thirds" get thrown around constantly, but what do they actually mean, and does it matter which one you choose?
Here's our plain-English guide to camera sensor sizes.
What is a camera sensor?
The sensor is the digital equivalent of film. It's the component inside your camera that captures light and converts it into an image. The size of that sensor has a significant impact on image quality, low-light performance, depth of field, and the lenses you can use.
The main sensor formats
Full Frame (35mm)
A full frame sensor measures 36mm x 24mm — the same dimensions as a frame of 35mm film. This is the largest sensor format found in mainstream interchangeable-lens cameras, and it's the benchmark against which all other formats are measured.
Advantages:
- Superior image quality, especially in low light
- Greater dynamic range and tonal depth
- Shallower depth of field for subject isolation
- Wider field of view with any given lens
- More detail in large prints
Best for: Professional photographers, wedding and portrait photographers, landscape photographers, and anyone who regularly shoots in low light or needs the highest possible image quality.
Browse full frame mirrorless cameras — including the Sony Alpha A7 series and Nikon Z full frame range.
APS-C (Crop Sensor)
APS-C sensors are smaller than full frame. Dimensions vary slightly by manufacturer: Sony, Nikon, Fujifilm, and Pentax sensors measure around 23.5mm x 15.6mm, while Canon's are slightly smaller at 22.3mm x 14.9mm. The name comes from the old Advanced Photo System film format.
Because the sensor is smaller, it captures a narrower field of view than a full frame sensor using the same lens — this is known as the crop factor, which is typically 1.5x for most brands and 1.6x for Canon. In practice, this means a 50mm lens on an APS-C camera behaves like a 75mm lens would on a full frame body — a real advantage if you shoot wildlife or sport and want extra reach from your telephoto lenses, but something to plan around if you shoot wide-angle. Always check whether a lens is designed for APS-C (sometimes labelled DX, EF-S, or E-mount APS-C) or full frame to avoid vignetting issues.
Advantages:
- Smaller, lighter camera bodies and lenses
- More affordable than full frame
- The crop factor effectively extends the reach of telephoto lenses — great for wildlife and sports
- Excellent image quality for most uses
Best for: Enthusiast photographers, travellers, wildlife and sports shooters, and anyone stepping up from a smartphone or compact camera who wants great image quality without the full frame price tag.
Browse APS-C DSLR cameras or explore APS-C mirrorless options.
Micro Four Thirds (MFT)
Micro Four Thirds sensors measure approximately 17.3mm x 13mm — roughly half the area of a full frame sensor. The format is used by OM System (formerly Olympus) and Panasonic Lumix, and has a 2x crop factor. Lenses designed for MFT cameras are labelled with focal lengths that already account for this, so a 25mm MFT lens delivers a 50mm equivalent field of view.
Advantages:
- Very compact and lightweight systems
- Excellent lens range with consistent quality
- Strong video capabilities, particularly in Panasonic bodies
- More affordable entry point
Best for: Travel photographers, videographers, and anyone who prioritises portability without sacrificing interchangeable lens flexibility.
Camera Sensor Size Comparison: A Complete Format Guide
The three formats above are the most common in interchangeable-lens cameras, but they're not the whole picture. Here's a breakdown of the most common camera sensor sizes from largest to smallest, including the smaller sensors found in compact cameras, drones, and action cams:
- Full Frame (35mm): 36mm x 24mm — found in professional DSLRs and mirrorless cameras like the Sony A7 series, Canon EOS R5, and Nikon Z6 III.
- APS-H: ~27.9mm x 18.6mm — rarely used today; previously appeared in some Canon 1D models.
- APS-C: ~23.5mm x 15.6mm (22.3mm x 14.9mm for Canon) — the most popular enthusiast format. Found in the Sony A6700, Fujifilm X-T5, Canon EOS R10, and Nikon Z50 II.
- Micro Four Thirds (4/3): 17.3mm x 13mm — used in Olympus (OM System) and Panasonic Lumix cameras. Compact and versatile.
- 1-inch sensor: ~13.2mm x 8.8mm — common in premium compact cameras and some drones, including the Sony RX100 series and DJI cameras.
- 1/1.7-inch sensor: ~7.6mm x 5.7mm — found in higher-end compact cameras.
- 1/2-inch sensor: ~6.4mm x 4.8mm — used in some compact cameras and older smartphone modules.
- 1/2.3-inch sensor: ~6.17mm x 4.55mm — standard in entry-level compact cameras and action cameras like GoPro.
The key takeaway is that as sensor size decreases, so does the camera's ability to capture light — which directly affects image quality in low-light conditions, dynamic range, and background blur. However, smaller sensors also enable smaller, lighter, and more affordable cameras, which is why they remain popular for travel, action, and everyday photography.
When choosing between formats, consider how and where you shoot most. A 1/2-inch sensor may be perfectly adequate for bright daylight social content, while a full frame or APS-C sensor becomes noticeably superior when the light gets challenging.
Does sensor size affect image quality?
Yes — but context matters. A larger sensor captures more light, which generally means better performance in low-light conditions, less digital noise at high ISO settings, and greater dynamic range. However, modern APS-C and MFT cameras have closed the gap significantly, and for most everyday shooting conditions, the differences are less dramatic than they once were.
The biggest practical differences show up when:
- Shooting in low light without flash
- Printing images at very large sizes
- Trying to achieve very shallow depth of field
- Shooting at very high ISO settings
APS-C vs Full Frame: Which Sensor Size Is Right for You?
The debate between APS-C and full frame is one of the most common questions we hear at Ted's Cameras — and the honest answer is that the "best" sensor size depends entirely on how you shoot, what you shoot, and what your budget looks like. Micro Four Thirds is also worth considering if portability is your top priority above all else.
Choose APS-C if:
- You're building your first serious camera kit and want more budget for lenses
- You shoot wildlife, sport, or birds in flight and want the extra reach a 1.5x crop factor provides
- You prioritise a smaller, lighter kit for travel or everyday carry
- You shoot mostly in good light conditions (outdoors, studio with controlled lighting)
- You're a content creator who values portability over maximum image quality
Choose Full Frame if:
- You regularly shoot in low light — events, weddings, concerts, or night photography
- You need the absolute maximum dynamic range and tonal detail for landscape or commercial work
- You want the shallowest possible depth of field for portraiture and subject isolation
- You're printing images at large sizes and need the extra resolution and detail full frame provides
- You're a working professional where image quality is a core part of your value to clients
To explore everything full-frame has to offer — including 4K video, APS-C comparisons, and key advantages — read our dedicated full-frame cameras guide.
It's also worth noting that the gap between APS-C and full frame has narrowed considerably in recent years. Cameras like the Fujifilm X-T5 and Sony A6700 produce images that are genuinely exceptional, and for many use cases — including professional work — APS-C is more than enough. The decision often comes down to the specific lenses you want to use and the shooting scenarios you most commonly face.
If you're unsure, we always recommend visiting a Ted's Cameras store to handle both options side by side. The difference in size and weight between an APS-C and full frame body can be just as important a factor as the sensor spec sheet.
For a deeper dive into how sensor size affects your lenses, read our guide to understanding digital camera crop factor.
Get expert advice at Ted's Cameras
Still not sure which sensor format is right for you? Our team across Ted's Cameras stores nationwide can help you find the right camera for your needs and budget. Browse our full camera range online or visit your nearest store today.