The Porst compact-reflex is a 35mm camera. It belongs to the group of SLR cameras and was built by the Japanese company Cosina for the German photo dealer. The 35mm camera was called at Cosina “Cosina CSM“.
The lenses of the Porst compact-reflex can be exchanged. For this purpose the camera is equipped with a M42 lens mount. M42 lenses are attached to the camera by means of a screw thread. There is no autofocus with the 35mm camera. You have to focus on the subject by hand.
The lens mount is very common. The first M42 optics was developed by Zeiss. Zeiss, KMZ, Voigtländer, Pentacon and Pentax were among others manufacturers of M42 interchangeable lenses.
The Porst compact-reflex has an integrated light meter. It is designed for an ISO range of 25 to 3200. The exposure measurement is performed through the lens. The aperture and exposure time can be freely adjusted according to the photographers wishes.
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. An external flash can be connected to the Hot Shoe. There is also a PC flash socket.
Films for the Porst compact-reflex
The Porst compact-reflex exposes cartridges with 35mm film. 35mm films are still produced today and are quite easy to get. For black-and-white 35mm shots, the AgfaPhoto APX 400* a good choice. For color images you can use the Fujifilm Superia 400*.
For example, a normal 35mm film can hold at this size a least 36 pictures. For the next frame, the photographer has manually wind the camera.
The Porst compact-reflex has a thread for a tripod and a connection for a cable release. In addition, there is a self-timer. The camera has a weight of 540 g. The dimensions are 13,65 x 8,32 x 5,1 cm. The needed energy for the camera is provided by two 1,5V S-76 batteries.
The 35mm camera can nowadays only be bought in used condition. The price for a used copy of the depends on the condition and functionality.
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 |
| Company name of the brand | Photo Porst |
| Manufacturer | Cosina |
| Country of production | Japan |
| Estimated value / Used price | 67,72 Euro Estimate based on used prices of 58 offers (possibly with different scope of delivery and/or condition). As of June 15, 2026 |
| Average used price in the year 2023 | 69,75 Euro (74.69 US-Dollar) |
| Average used price in the year 2024 | 76,63 Euro (82.26 US-Dollar) |
| Average used price in the year 2025 | 76,17 Euro (82.26 US-Dollar) |
FAQ about the Porst compact-reflex
Is the Porst compact-reflex a manual focus camera?
Yes, it's a manual focus camera. It doesn't have autofocus; you need to manually adjust the focus ring on the lens to get sharp images. This gives you more control over the image.
What kind of lenses does this camera use?
The Porst compact-reflex uses interchangeable M42 lenses. These are screw-mount lenses, and many different brands made them, so you have a lot of options.
How do I take long exposure photos with this 35mm camera?
It has a bulb mode. In bulb mode, the shutter stays open as long as you hold down the shutter release button, allowing for long exposures. Remember to use a tripod for sharp results.
What type of film does the camera take?
The Porst compact-reflex uses standard 35mm film. Both color negative and black and white films are compatible. These are readily available from most photo retailers.
Does the camera have a built-in light meter?
Yes, it has a built-in light meter for setting exposure. The meter works through the lens and covers an ISO range from 25 to 3200, giving you flexibility with film choices.