The Cosina CSM is a single lens reflex camera. The 35mm camera was built by Cosina. The 35mm photo camera was also called “Porst compact-reflex” and sold at stores in Germany.
The lenses of the Cosina CSM can be changed. A M42 lens mount was installed for this purpose. For the M42 lens mount there are a lot of screw mount lenses available. The lens thread was developed in the 1930s at Carl Zeiss in Jena, Germany. Large producers of M42 lenses were Pentax, Zeiss, Pentacon and KMZ. The Cosina CSM does not provide autofocus system. Focusing is manual.
The Cosina CSM is fitted with a built-in light meter. It can be used for films in an ISO range of 25 to 3200. The exposure meter is designed to measure exposure through the lens of the camera. The aperture and shutter speed are freely adjustable.
The Bulb mode can be used for long exposures. In this mode, the film is exposed as long as the shutter release button is pressed. A flash unit can be used via the hot shoe or the PC flash connection.
Films for the Cosina CSM
Without photo films, nothing works with the Cosina CSM. The camera needs 35mm films more precisely. 35mm films are still produced today. They can be developed in most photo laboratories. A 35mm film for color pictures is the Kodak Ultramax 400*. A possible black and white film is the AgfaPhoto APX 100*
The colour film is a colour negative film and must be developed in the C-41 process. The C-41 process is offered by almost every photo lab. The Cosina CSM exposes an area of 24 mm x 36 mm.
In the Cosina CSM is a thread for a tripod built-in. In addition, there is a connector for a cable release and a self-timer. The dimensions of the 35mm camera are 13,65 x 8,32 x 5,1 cm. At this size her weight is 540 g. The power supply for the 35mm camera is provided by two 1,5V S-76 batteries.
The Cosina CSM can today only found in used condition. The value of a used copy depends primarily on if it works correctly and in what condition the copy is.
Technical datasheet
| Attribute | Specification |
|---|---|
| Type of Camera | Single lens reflex camera |
| Film format | 35mm |
| Picture format | 24 mm x 36 mm |
| Lens mount | M42 lens mount |
| Focus | Manual |
| Viewfinder | Pentaprism finder |
| Exposure times | 1/1000 second to 4 seconds, Bulb |
| Bulb mode | Yes |
| Light meter | Yes |
| Built-in flash | No |
| Flash Connection | Hot Shoe, PC-Flash |
| Flash sync speed | 1/60 s |
| Tripod mount | Yes |
| Cable release thread | Yes |
| Self-timer | Yes |
| Power supply | 2x S76 batteries |
| Size | 13,65 x 8,32 x 5,1 cm |
| Dimensions in inches | 5.37 x 3.28 x 2.01 inches |
| Weight | 540 Grams |
| Estimated value / Used price | 99,10 Euro Estimate based on used prices of 3 offers (possibly with different scope of delivery and/or condition). As of April 13, 2026 |
| Average used price in the year 2023 | 82,58 Euro (88.76 US-Dollar) |
| Average used price in the year 2024 | 92,96 Euro (99.58 US-Dollar) |
| Average used price in the year 2025 | 94,83 Euro (101.75 US-Dollar) |
FAQ about the Cosina CSM
Is this camera automatic or do I have to focus manually?
The Cosina CSM is a manual focus camera. It doesn't have autofocus, so you'll need to adjust the focus yourself using the lens. This gives you more control over the image but requires practice.
What kind of lenses can I use with my new camera?
The Cosina CSM uses M42 lenses. This is a very popular screw mount, so many different lenses are available from various manufacturers, both new and old. This means lots of options for photography.
How do I use a flash with the camera?
You can attach a flash to the Cosina CSM using either its hot shoe or PC sync terminal. This allows for easy flash photography, both on-camera and off-camera if you are experienced.
What type of film does this 35mm camera use?
The Cosina CSM uses standard 35mm film. You can use color negative, black and white, or other types of 35mm film. Many types are readily available from camera shops.
What is the size of the pictures the camera takes?
The Cosina CSM takes pictures measuring 24mm x 36mm. This is the standard size for 35mm film cameras, which is also often referred to as 'full-frame' in the context of smaller digital sensors.