1 Purpose and Functions
A high-quality professional 25mm focal length glass lens designed specifically for high-resolution CCTV systems. The ACTii AC3321 lens is fully optimized for use with megapixel cameras (5MP, 4MP, 3MP, 2MP, 1MP) as well as traditional analog cameras. Thanks to an advanced lens design, the device guarantees perfect sharpness not only in the center of the frame but also at its corners, which is crucial for identification and surveillance systems.
Main features:
- ✔ Construction based on high-quality glass components and a metal housing.
- ✔ Full compatibility with HD megapixel cameras: 5MP, 4MP, 3MP, 2MP, 1MP.
- ✔ Fixed 25mm focal length providing a narrow field of view (9°) for precise detail observation.
- ✔ Infrared (IR) correction adapted for day/night operation.
- ✔ Eliminated corner blur effect thanks to dedicated MP optics.
- ✔ Integrated IR filter ensuring natural color reproduction.
Optional extensions:
In very bright sunlight, to achieve perfect color fidelity, it is recommended to use an additional IR 650 filter (model ACTii AC6508), which is mounted on the rear part of the lens.
2 Technical Specification
| Lens Focal Length | Fixed, 25mm, 1/2" |
| Field of View (1/3 sensor) | 9° |
| Aperture | F2.0 |
| Supported Resolutions | 5MP, 4MP, 3MP, 2MP, 1MP and analog |
| Mount | M12x0.5 (S-MOUNT), 11.9mm thread |
| Material | Metal housing, glass optics |
| Infrared Filter | Yes, with chromatic aberration correction |
| Product Dimensions | 14 x 14 x 18 mm |
| Weight | 5 g (net), 7 g (with packaging) |
| Certificates | CE, RoHS |
3 Installation and Configuration
Lens mounting:
The lens is designed for board cameras with an M12 socket. To install the device:
- Ensure the camera power is disconnected before starting installation.
- Carefully screw the lens into the M12 threaded socket on the camera board.
- Connect the camera to a monitor to get a live image preview.
- Adjust the focus by slowly rotating the lens clockwise or counter-clockwise until you obtain the clearest image.
- After setting the focus, lock the lens using the locking ring (if provided with the camera).
Important tips:
- Do not touch the glass surfaces with your fingers – grease can permanently damage the anti-reflective coatings.
- When mounting in outdoor housings, ensure that the lens does not touch the front glass of the housing.
4 Safety and Maintenance
Rules for safe use:
- ● The product should be protected from direct exposure to strong acids and bases.
- ● Avoid exposing the lens to sudden mechanical shocks that may decenter the lens system.
- ● Store in a dry place, free from dust and moisture.
Optics maintenance:
To clean the lenses, use only specialized microfiber cloths or compressed air. Do not use aggressive detergents or solvents. In case of heavy dirt, you can use a small amount of pure isopropyl alcohol applied to a soft cloth.
5 Troubleshooting
| Problem | Possible cause and solution |
|---|---|
| Image is blurry | Requires adjustment by rotating the lens in the socket. Check if the lens is screwed in fully or if it encounters mechanical resistance. |
| White spots on the image at night | Reflection of IR LEDs from the housing glass. Ensure the lens is tightly sealed with a rubber collar from the IR illuminator. |
| Unnatural colors (e.g., pink tint) | Lack of an active IR-CUT filter in the camera or the need to use an additional external IR 650 filter in very strong daylight. |