The Olympus Pen F, Pen FT and Pen FV were very similar half-frame 35 mm

135 film

The term 135 was introduced by Kodak in 1934 as a designation for cartridge film wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film format...

 single-lens reflex (SLR) camera

Camera

A camera is a device that records and stores images. These images may be still photographs or moving images such as videos or movies. The term camera comes from the camera obscura , an early mechanism for projecting images...

s with interchangeable lenses produced by Olympus of Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 between 1963-1966 (Pen F), 1966-1972 (Pen FT) and 1967-1970 (Pen FV). The chief difference between them was that the Pen FT had an integrated light meter

Light meter

A light meter is a device used to measure the amount of light. In photography, a light meter is often used to determine the proper exposure for a photograph...

, while the F and FV did not.

Half frame meant that the camera used a 18×24 mm vertical (portrait

Portrait

thumb|250px|right|Portrait of [[Thomas Jefferson]] by [[Rembrandt Peale]], 1805. [[New-York Historical Society]].A portrait is a painting, photograph, sculpture, or other artistic representation of a person, in which the face and its expression is predominant. The intent is to display the likeness,...

) format, producing twice the pictures on a roll of 135 film as the regular 36×24 mm format. The smaller image format also allowed for a smaller camera and lenses, making the Pen F system one of the smallest SLR systems ever made; the Pentax Auto 110

Pentax Auto 110

The Pentax Auto 110 and Pentax Auto 110 Super are single-lens reflex cameras made by Asahi Pentax that use Kodak's 110 film cartridge. The Auto 110 was introduced with three interchangeable lenses in 1978. Three more lenses were introduced in 1981, and then the Super model was released in 1982....

 was smaller, but with a much more limited range of lenses and accessories, and smaller 110 film

110 film

110 is a cartridge-based film format used in still photography. It was introduced by Kodak in 1972. 110 is a miniaturised version of Kodak's earlier 126 film format. Each frame is , with one registration hole....

.

These cameras were somewhat exceptional since they used a rotary

Rotary disc shutter

A rotary disc shutter is a type of shutter. It is notably used in motion picture cameras.Rotary discs are semicircular mirrors which rotate in front of the film gate, and thus expose the film. As the mirror spins it reflects the image onto the ground glass so that it can be viewed by the camera...

 focal-plane shutter

Focal-plane shutter

In camera design, a focal-plane shutter is a type of photographic shutter that is positioned immediately in front of the focal plane of the camera, that is, right in front of the photographic film or image sensor.-Two-curtain shutters:...

, rather than the two-curtain focal-plane shutter commonly used in other SLRs. Since this one-piece shutter opens fully before it starts to close, it can synchronize to electronic flash at all shutter speeds.

Pen-F series cameras are occasionally modified to mount standard motion picture camera lenses for use as film test cameras with 35mm motion picture films. The Pen-F frame size is close to the 35mm motion picture Super 35 frame.

Lens manufactured for the Olympus Pen F System

Type	Lens	Foc.Leng.(mm) F	35mm equiv. 35 mm equivalent focal length In photography, the 35 mm equivalent focal length is a measure that indicates the angle of view of a particular combination of a camera lens and film or sensor size...	Angle of view	Gr.-El.	TTL-No.	F/stop range	Min. Focus	Filter	Weight
Wide	G Zuiko AUTO W	20mm F3.5	28mm	73°	6-7	0-4	3.5–16	0.2m	43mm	145g
	E Zuiko AUTO W	25mm F4	35mm	62°	5-5	0-4	4–16	0.25m	43mm	120g
	G Zuiko AUTO W	25mm F2.8	35mm	62°	5-7	0-5	2.8–16	0.25m	43mm	160g
Standard	F Zuiko AUTO S	38mm F1.8	55mm	43°	5-6	0-6	1.8–16	0.35m	43mm	135g
	G Zuiko AUTO S	40mm F1.4	58mm	41°	6-7	0-6	1.4–16	0.35m	43mm	165g
	H Zuiko AUTO S	42mm F1.2	60mm	39°	6-8	0-6	1.2–16	0.35m	49mm	255g
Telephoto	G Zuiko AUTO T	60mm F1.5	85mm	28°	5-7	0-6	1.5–16	0.8m	49mm	270g
	F Zuiko AUTO T	70mm F2	100mm	24°	5-6	0.5-7	2–22	0.8m	43mm	230g
	E Zuiko AUTO T	100mm F3.5	140mm	17°	4-5	1-6	3.5–22	1.5m	43mm	250g
	E Zuiko AUTO T	150mm F4	210mm	12°	4-5	1-5	4–22	1.7m	49mm	380g
Super Telephoto	E Zuiko T	250mm F5	360mm	7°	3-5	1-6	5–32*M	3.5m	58mm	800g
	E Zuiko T	400mm F6.3	570mm	4°	4-5	1-5	6.3–32*M	5m	72mm	1750g
	Zuiko Mirror T	800mm F8	1150mm	2°	4-5	-	8	16m	25.5mm	2400g
Zoom	Zuiko AUTOZOOM	50–90mm F3.5	70–130mm	34–19°	8-10	0.5-4	3.5–16	1.5m	49mm	420g
	Zuiko ZOOM	100–200mm F5	140–280mm	17-9°	9-12	1-6	5–32*M	1.7m	49mm	700g
Others	E Zuiko AUTO S	38mm F2.8	55mm	43°	4-5	0-5	2.8–16	0.8m	43mm	70g
	D Zuiko AUTO S	38mm F2.8	55mm	43°	3-4	0-5	2.8–16	0.35m	43mm	125g
	E Zuiko AUTO MACRO	38mm F3.5	55mm	43°	4-5	0-4	3.5–16	0.156m	43mm	200g

• *M=manual diaphragm