Olympus PEN E-P3

The Micro Four Thirds (MFT) system design standard was jointly announced in 2008[3] by Olympus and Panasonic, as a further evolution of the similarly named predecessor Four Thirds System pioneered by Olympus.[4] The Micro Four-Thirds system standard uses the same sized sensor (nominal 4000 pixels by 3000 pixels) as the original Four Thirds system. One potential advantage of the smaller MFT system sensor (when compared to market leaders Canon and Nikon APS-C and full frame sized) are smaller and lighter lenses. The smaller MFT sensor allows for a reduced image circle, which allows the development of smaller and lighter native lenses. The MFT sensor has a crop factor of 2.0 when compared to 35mm film equivalent full frame sensors. By comparison, the more popular consumer (as opposed to professional) DSLRs such as those made by Canon, Nikon and Sony have 1.5 to 1.6 crop factor APS-C sensors, which means larger and heavier lens designs. For example, a typical Olympus MFT M.Zuiko 14-42mm f/3.5–5.6 kit lens weighs 112 grams (4.0 oz), is 56 millimetres (2.2 in) in diameter and 50 millimetres (2.0 in) in length.[5] The equivalent Canon APS-C DSLR EF-S 18-55mm f3.5–5.6 kit lens weighs 190g, and is 69mm in diameter and 80mm in length[6]

While the older Four Thirds system design standard allowed the incorporation of a single lens reflex (SLR) camera design including a mirror box and pentaprism based optical viewfinder system, the MFT system design standard sought to pursue a technically different camera, and specifically slimmed down the key physical specifications which eliminated the ability to include the traditional complex optical path and the bulky mirror box needed for a SLR optical viewfinder. Instead, MFT uses either a built-in (Panasonic) or optional (Olympus/Panasonic) compact electronic viewfinder (EVF) and/or LCD back panel displaying a Live view from the main image sensor. Use of an EVF/back panel LCD and smaller four thirds image sensor format and allows for smaller and lighter camera bodies and lenses. The MFT system standard also specifically includes seamless switching between still photography and HD video recording as a design criterion.

MFT cameras are physically slimmer than most interchangeable lens cameras because the standard specifies a much reduced lens mount flange to imaging sensor plane distance of just 20 millimetres (0.79 in). Typically this so-called flange focal distance is over 40 millimetres (1.6 in) on most interchangeable lens cameras.[7] The MFT system design flange focal length distance allows for, through use of an adapter, the possibility to mount virtually any manufacturer's existing and legacy still camera interchangeable lens (as well as some video and cine lenses) to an MFT body, albeit using manual focus and manual aperture control. For example, many theoretically obsolete 35mm film camera lenses, as well as existing current lenses for APS-C and full frame DSLR's are now usable on MFT cameras. As an example, an older (i.e., used, obsolete and low priced), but still high quality, 50mm f/1.8 "standard" lens from a 35mm film camera can be used on a MFT camera body. With MFT sensors having a crop factor of 2.0, the old 50mm f/1.8 "standard" lens becomes a high-speed (although manual) 100mm f/1.8 telephoto portrait lens. So the MFT system allows the re-use of expensive lenses that may have outlived their 35mm film format camera, and can be used on a modern digital camera body capable of both still and HD video recording. Similarly, the MFT system design allows current DSLR lenses to be used as well, although only with manual focus and aperture control.

• Addition of an Accessory Port that can be used for an electronic viewfinder or external microphone
• The E-P1 has six art filters, while the E-P3 now has ten art filters: Pop Art, Soft Focus, Pale & Light Color, Light Tone, Grainy Film, Pin Hole, Diorama, Cross Process, Gentle Sepia and Dramatic Tone
• Black finish widely available, silver finish available in Japan
• Auto focus tracking
• AF Illuminator and 32 Auto Focus points
• 3-inch OLED Touch Screen
• Colour boosting function named i-Enhance

• 1080i Full HD video at 60i frames per second (frame/s) and 720p Full HD video at 60p frames per second (frame/s)[8]

• Olympus PEN E-PL1
• Mirrorless interchangeable-lens camera

Media related to Olympus E-P3 at Wikimedia Commons

• Olympus PEN E-P3 Product Site
• Olympus PEN E-P3 Press Release