The Cosina CT-7 is a 35mm camera. It belongs to the SLR group and was also sold in North America as Quantaray RZ 800 (Ritz Camera) and Petri GX-4.
The lens of the Cosina CT-7 is interchangeable. Lenses with a Pentax K bayonet can be used with the camera. The model has no autofocus. It is manually focused.
The 35 mm camera has an exposure meter. The exposure meter is designed for films with a speed of ISO 25 to ISO 3200. The correct exposure is measured through the lens of the SLR camera.
The camera comes with an aperture preselection mode. The aperture and exposure time are also freely adjustable. If you want to take long time pictures, there is the bulb-setting. The closure remains open as desired. A flash unit can be used via the hot shoe or the PC flash connection.
Films for the Cosina CT-7
Photographic films are required for the Cosina CT-7. Films for the 35mm format are used. 35mm films are still produced today and are quite easy to get. Possible films for the model are the Kodak Gold 200* for color images and the Ilford Delta 100* for black and white shots.
The color film is being developed in the C-41 process. The C-41 process is offered by almost every photo lab. The negatives of camera have a size of 24 mm x 36 mm. A 135-36 film can hold at least 36 shots.
The Cosina CT-7 can be triggered by a self-timer or an additional cable release. A thread for a tripod is available. The camera needs two LR44 batteries (eBay / Amazon*).
The Cosina CT-7 you can only buy used. Depending on the state of the camera, the price for a used copy vary.
Technical datasheet
| Attribute | Specification |
|---|---|
| Type of Camera | Single lens reflex camera |
| Film format | 35mm |
| Picture format | 24 mm x 36 mm |
| Lens mount | Pentax K lens mount |
| Focus | Manual |
| Exposure times | 1/1000 second to 8 seconds, Bulb |
| Bulb mode | Yes |
| Light meter | Yes |
| Built-in flash | No |
| Flash Connection | Hot Shoe, PC-Flash |
| Flash sync speed | 1/100 s |
| Tripod mount | Yes |
| Cable release thread | Yes |
| Self-timer | Yes |
| Power supply | 2x LR44 batteries |
| Estimated value / Used price | 122,67 Euro Estimate based on used prices of 3 offers (possibly with different scope of delivery and/or condition). As of May 18, 2026 |
| Average used price in the year 2023 | 80,72 Euro (86.59 US-Dollar) |
| Average used price in the year 2024 | 110,22 Euro (119.06 US-Dollar) |
| Average used price in the year 2025 | 123,21 Euro (133.14 US-Dollar) |
FAQ about the Cosina CT-7
Is the Cosina CT-7 an automatic camera?
No, the Cosina CT-7 is a manual focus camera. You adjust the focus yourself, and it doesn't have autofocus capabilities. This gives you more control over your shots.
What kind of lenses can I use with this camera?
The Cosina CT-7 uses Pentax K-mount lenses. This means you can use a wide variety of lenses, giving you flexibility in your photography.
How do I take long exposure photos with the camera?
The Cosina CT-7 has a bulb setting. In this mode, the shutter stays open as long as you hold the shutter button down, allowing for long exposures.
What film size does this SLR use?
It uses standard 35mm film. This is a common and readily available film format, making it easy to find and use.
Can I use a flash with the Cosina CT-7?
Yes, it has a hot shoe and a PC flash connection, so you can attach and use an external flash unit to take photos in low light conditions.