Pentax 645

The Pentax 645 is an analog medium format camera from the Japanese manufacturer Pentax.

Overview of the functions

The Pentax 645 is a system camera with interchangeable lenses. It has several automatic exposure modes and a bulb mode. Focusing is manual. Film is advanced automatically (relatively loudly). There is a single frame and continuous mode.

The Pentax 645 comes with a handgrip that is also detachable. It also has two threads for a tripod and a connection for a cable release. A camera strap can be attached to the Pentax 645.

The top with the controls

The bottom with the tripod thread

Mount for the cable release

Technical data

Type of camera: SLR camera
Exposure format: 4.5 x 6 cm
Exposure range: 41.5 x 56 mm
Lens mount: Pentax 645 A bayonet, with adapter other lenses
Exposure programs: program automatic, time automatic, aperture automatic, tracking metering, programmed flash automatic and flash internal metering
Exposure meter: Built-in; center-weighted open-aperture metering with gallium photodiodes; additional film surface metering for flash internal metering
Measuring range: EV 3 (1 second at f/2.8 aperture) – EV 19 (1/1000s at f/22) with 75mm f/2.8 lens at ISO 100
Exposure compensation: +3 to -3
Shutter type: Electronically controlled focal plane shutter, vertical travel
Exposure times: 1/1000 s to 15 s, Bulb
Multiple exposure: Possible.

Film format: 120 roll film, 220 roll film, 70 mm perforated roll film (film back suitable for each format)
Frames per film: 15 frames (120), 30 frames (220), approx. 90 frames (70 mm)
Film transport: Automatic film transport by built-in motor; single frame (1 frame per second) or continuous mode (1.5 frames per second)

Finder: Standard ground glass with split-image indicator and microprism ring
Information in viewfinder: LED display for aperture value, exposure time, exposure compensation. Other indicators
Field of viewfinder: 92% vertical, 93% horizontal.
Ocular correction: -5 to +2 dpt.

Power supply: 6 AA batteries for metering, film advance, and exposure indicator.
Battery for memory function: CR 1220
Standby: After 30 seconds, metering system is turned off

Dimensions: 96 (W) x 109 (H) x 116.5 (D) mm without handle; 145.4 (W) x 109 (H) x 116.5 (D) mm with handle
Weight: Housing: 985 grams, handle 137.5 grams, total weight: 1284 grams

Films

The Pentax 645 is a medium format camera and therefore needs medium format films. Both 120 and 220 films are supported. For this, the respective film inserts are needed. The film is wound into these and then inserted. Swapping in the middle of a roll, as with Hasselblad, is not possible.

The Pentax 645 exposes an area of 45 mm by 60 mm, although the exact area is somewhat smaller (41.5 x 56 mm). A roll of 120 film will fit 15 frames. With 220 film, it’s 30 frames.

The light meter supports a wide range of film speeds. Films from ISO 6 to ISO 6400 can be exposed with the Pentax 645. Thus, it covers practically the entire film spectrum. Be it a Fujifilm Velvia 50 slide film to a Kodak Portra 400 color negative film to an Ilford Delta 3200 black and white film. Two solid films are the Kodak Portra 400* for color images and the Ilford XP2 Super* for black and white. Both films can be used flexibly and are therefore also perfect for events, such as weddings, where you don’t yet know exactly what the lighting conditions in the location will be like.

Film holder for 120 film

A roll of medium format film with the camera

Batteries

The Pentax 645 needs power for metering and transporting the film, among other things. The main source is six AA batteries (eBay / Amazon*). The batteries are located in the handle of the camera. They do not need to be changed often; according to Pentax, about 100 rolls of 120 roll film are possible with one charge. The battery life and common battery type are plus points for the Pentax 645, the Contax 645 requires very exotic batteries in comparison and they are much less productive than the six AA batteries.

Additionally, there is a button cell in the lower part of the camera. The CR 1220 ensures that the camera’s data, such as the current image (frame counter) and exposure compensation, remain stored, even if the handle, and thus the main power supply, has been removed. The service life is 5 years. However, the battery is not necessary for normal photography.

The holder with six AA batteries

Lenses

The Pentax 645 comes with its own Pentax 645 bayonet. There is a good selection of lenses for the system. The SMC Pentax-A 75mm f/2.8 is a standard lens for the 645 and is roughly equivalent to a 50mm on a 35mm camera. The crop factor compared to a 35mm camera is 0.62.

The A series was designed for the Pentax 645. Later, the autofocus lenses (FA series) followed. The abbreviation “SMC” stands for Super-Multi-Coated. The coating technology was patented by Pentax in 1971. The lens coating process is said to seknk the reflectance to only 0.2% per lens surface. The result is a dramatic improvement in color fidelity and brightness, as well as the elimination of flare and ghosting.

However, other medium format lenses can also be adapted with a lens adapter. Adapters for different lens bayonets are offered by various manufacturers. One supplier is K&F Concept from Shenzhen, China.

Lenses for the Pentax 6×7 system are often used with the 645. Such as the Pentax 6×7 Super-Multi-Coated Takumar 105 mm f/2.4.

An adapter from K&F Concept for Pentax 6x7 lenses on 645 bodies

The Pentax 6x7 105mm f/2.4 on a Pentax 645 with the K&F Concept adapter

ND filter for the camera

Filters can of course be used with the Pentax 645. From color, infrared, UV and up to ND filters, there are no limits to creativity.

Comparison with a roll of 120 medium format film

Size comparison with a Canon AE-1 (35mm)

Photographing with the Pentax 645

Exposure modes

Program Auto
Camera sets aperture (lens must be set to “A”)
Camera sets exposure time

Time Auto 1
Photographer sets aperture (on camera) (lens must be set to “A”)
Camera sets exposure time automatically

Aperture automatic
Camera sets aperture (lens must be set to “A”)
Photographer sets exposure time

Time auto 2
Photographer sets aperture (on lens)
Camera automatically selects exposure time

Tracking / manual mode
Photographer sets aperture on lens
Photographer sets exposure time

60 (sync speed)
For shooting with flash units
Camera sets 1/60 second

Bulb / long exposure
Photographer sets aperture
Shutter open while shutter button is held down

Multiple exposures
Multiple exposures are easy with the Pentax 645. There is a ring on the left side of the camera (M.E.) for this purpose. This must be turned in the direction of the arrow while applying light pressure until it clicks into place before taking the first picture. Now the first picture can be taken. The film is not transported further and the ring jumps back to the starting position.

If you only want to take a double exposure with the Pentax, you can now take the second exposure. After that, the film is transported normally again and you can take a new picture. Otherwise, the multiple exposure ring must be operated again.

The multiple exposure ring may only be operated when the film is loaded correctly.

Photographing without film
If no film insert is in the camera, only three exposure modes can be used. These are M 1000, 60 and B.

Pentax 645 for portrait photography

The Pentax 645 is especially popular with portrait photographers. It is a cheaper alternative to the Contax 645 and delivers comparable results. The large film format allows for a nice depth of field and high resolution. Nevertheless, the Pentax 645 is mobile. The automatic film transport makes it possible to work quickly, but it can also be scary (keyword: loudness).

Analogue Love

Other models

The Pentax 645 is the first model in the series. It was later followed by the Pentax 645N and the Pentax 645N II. The 645N was introduced in 1997 and heralded the arrival of autofocus for the Pentax 645 system. It also revised the design of the controls, incorporated a self-timer, imprints in the film (shooting data is imprinted on the edge of the film) and matrix metering, and improved the continuous shooting function to 2 frames per second. In 2001, the Pentax 645N II followed. The main innovation was the mirror lockup.

Buy Pentax 645

Where can you buy the Pentax 645 today and what price do you have to put down for it?
Of course, the medium format camera is no longer manufactured today, so you can only get it on the used market. The value of a used Pentax 645 body is about 150 to 300 Euros, depending on the condition and accessories. The price for the later models (Pentax 645N and 645N II) is significantly higher.

Sample photos

Lomography Color Negative 800 120 (expired)

Lomography Color Negative 800 120 (expired)

Kodak Portra 160 NC

Fujifilm Velvia

Portra 160 NC

All pictures were taken with the Pentax 6×7 105 mm f/2.4 lens. The negatives were digitized with a Canoscan 9000F.