Camera Categories Types

I am a stills photographer. I do not shoot any video, and do not use specialised devices such as drones, or underwater, trail or film cameras. This post, as with all other photography-related posts on this website therefore discusses stills photography only, and is aimed at beginning stills photographers.

Except where indicated, the information in this post was retrieved from Sensor Size Comparison: Find Your Best Camera Fit. You should read that post for greater detail.

There are many different ways to categorise cameras. For example, cameras can be categorised by media type; sensor size; single or interchangeable lens; viewfinder, electronic screen, or rangefinder; and so forth. In this post, I will attempt to classify, clarify, and cross-reference these categories. So let’s begin.

Sensor Types

Digital cameras use one of two sensor types: Charge Coupled Device (CCD) and Complementary Metal-Oxide-Semiconductor (CMOS). CCD sensors were used in cameras up until about 2005 or so, with CMOS sensors being used from the early 2000’s onwards.

CCD sensors have traditionally produced higher quality, lower noise images. CMOS sensors are more power efficient, and have advanced to be just about on par with CCD sensors in terms of quality and noise performance. For a detailed discussion of the differences between CCD and CMOS sensors, and how camera sensors work, see What is the Difference Between a CCD and CMOS Camera Sensor?. Since all sensors in modern still photography cameras are CMOS type, the differences are not germaine to this discussion.

Sensor Sizes

Sensor size (both physical dimensions and the number of pixels on the sensor) affects a number of characteristics, such as low light performance, depth of field, and out of focus quality (bokeh). For example, a 1/2.3 sensor has extremely poor low light performance, but larger depth of field (the amount of the image that appears in focus) and much less bokeh for the same lens aperture setting than any of the larger sensors.

Sensor size also affects the size of lenses required to cover the full area of the sensor. For each increase in sensor size, lenses must be larger in diameter and therefore are heavier in weight. Compare, for example, the lenses for the cameras in your smartphone to the lenses on a typical full frame camera.

Size Name	Physical Size	Crop Factor	Pixel Density	Low Light Performance
1/2.3*	6.17mm x 4.55mm	5.64	up to about 14 MPixels	very poor
1 Inch (1in)**	13.2mm x 8.8mm	2.7	3 to 48 MPixels	poor
Micro Four Thirds (MFT)	17.3mm x 13mm	2	16 to 20 MPixels	fair
APS-C	24mm x 16mm***	1.5 to 1.6	20 to 35 MPixels	good
Full Frame (FF)	36mm x 24mm	1	20 to 60 MPixels	better
Large and Medium Format (LF)	up to 53.4mm x 40mm**	0.64	50 to above 100 MPixels	best

*There are actually a number of different size designations ranging from 1/3 to 1/1.7 with corresponding physical size differences, but 1/2.3 is the most common, and therefore the only one listed here.

**Called 1 Inch for historical reasons.

***Canon’s APS-C sensors are 22.5mm x 15mm.

**Fujifilm GFX cameras have a sensor size of 43.8mm x 32.9mm.¹

Camera Types

DSLR

• interchangeable lenses
• sensor is fronted by a two screen shutter which is in turn fronted by a mirror that diverts the light entering the camera into a pentaprism and then out the viewfinder.
• some DSLRs also have a rear electronic screen which may display the same image as the viewfinder.
• any of large and medium format, full frame, APS-C, and Micro four Thirds
• When the shutter button is pressed, the screen flips up out of the way, first shutter screen opens, and at the end of the exposure, the second shutter screen closes. Mirrorless
• interchangeable lenses
• sensor may be fronted by a one or two screen shutter which remains open. The sensor is read continuously and the image is fed directly to an electronic viewfinder or electronic screen on the rear of the camera.
• Point and shoot
• automatic settings making it simple to use
• usually 1/2.3 sensor
• fixed lens with either a fixed focal length or small zoom range (1-3x is typical)
• poor low light performance Compact
• similar in size to point and shoot, but with advanced camera settings
• may have larger sensor than point and shoot. At least one has a full frame sensor.
• fixed lens with either a fixed focal length or small zoom range (1-3 types is typical)
• poor low light performance Bridge
• fixed lens with very large zoom range (1-24x up to 1-60x)
• usually 1/2.3 sensor size so poor low light performance Large and Medium format Smartphone Rangefinder

Sensor Sizes 1/3 to 1/1.7 1/2.3 is a typical size, about 6.17mm x 4.55mm budget point and shoot cameras older smartphones and entry level phones pocket zoom cameras poor low light performance

1 Inch 13.2mm x 8.8mm (actually 15.9mm diagonal, not 25.4mm which is 1 inch) newer smartphones poor low light performance, but better than 1/2.3

Micro Four Thirds 17.3mm x 13mm offers balance between compact camera and lens size, and performance better low light performance than 1 inch sensor, but poorer than APS-C

APS-C 22.5mm x 15mm (Canon) to 24mm x 16mm (Other manufacturers) good balance between image quality, low light performance, and cost

Full Frame 36mm x 24mm (same as 35mm film) very good image quality, low light performance, and superior depth of field control

Large Format 43.8mm x 32.9mm (Fujifilm GFX) up to 53.4mm x 40mm best image quality, incredible depth of field significantly more expensive than full frame bodies and lenses

Camera Type vs Lens Type

Type	fixed focal length	zoom	interchangeable
Point and Shoot	✓	✓
Compact	✓	✓
Smartphone	✓
Bridge		✓
Rangefinder	✓
DSLR			✓
Mirrorless			✓

Camera Type vs Sensor Size

Type	1/2.3	1in	MFT	APS-C	FF	LF
Point and Shoot	✓	✓
Compact	✓	✓			rare
Smartphone	✓	✓
Bridge	✓	✓
Rangefinder				✓	✓
DSLR				✓	✓
Mirrorless			✓	✓	✓	✓

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