Hanwha SLA-2812DN 2.8-12mm CS-Mount DC Auto Iris Varifocal Lens
Overview
The Hanwha SLA-2812DN is a CS-mount varifocal lens designed for box-style IP and analog cameras using a 1/3" image sensor. Its 2.8–12mm focal range covers everything from a wide lobby view down to a tighter corridor or parking-lane shot — without swapping lenses. The F1.3 DC-type auto iris keeps exposure stable as lighting conditions change, making this lens a practical choice for scenes where ambient light varies throughout the day, such as building entrances with mixed interior and natural light.
Key Features
- 2.8–12mm Varifocal Range: A roughly 4× manual zoom range means one lens can handle the field-of-view adjustments you would otherwise need multiple fixed lenses for. Dial in the exact coverage angle during commissioning rather than guessing at install time.
- F1.3 DC-Type Auto Iris: The auto iris adjusts mechanically in response to changing light levels — critical for entryways, perimeter walls, or any scene cycling from bright daylight to dim artificial light. DC-type control integrates directly with the camera body's iris driver circuit; confirm your camera supports DC-type auto iris before purchasing.
- 1/3" Sensor Format: Sized for the most common sensor format in the Hanwha box-camera line and compatible with 1/3" sensors from other manufacturers. Using this lens on a larger sensor (1/2" or bigger) will introduce vignetting at wide focal settings — match sensor format carefully.
- CS-Mount Interface: The CS-mount standard is widely supported across Hanwha box cameras and many third-party units. If your camera has a C-mount body, a 5mm C-to-CS adapter ring is required (not included).
- White Housing: Finished in white to blend with ceiling-mounted or wall-bracket installations in commercial interiors where a discrete appearance is a project requirement.
Integration & Compatibility
The SLA-2812DN (often searched as SLA 2812DN) is designed for use with Hanwha box cameras in the Hanwha surveillance line that accept CS-mount lenses and include an on-board DC iris driver. It is also broadly compatible with third-party box-style IP cameras supporting the CS-mount standard with a 1/3" sensor. When pairing with a new camera platform, verify that the camera body provides a DC iris control voltage output — not all box cameras do, and an incompatible iris type will result in either a fully open or fully closed iris with no auto-exposure control. For help sizing lenses to specific camera models or field-of-view requirements, the camera lens selection guide covers focal length calculations and sensor format matching in detail. If you are building out a complete recording system, pairing this lens with an appropriate network video recorder and compatible box camera will determine final image quality and storage requirements.
Frequently Asked Questions
Q: What cameras is the SLA-2812DN compatible with?
A: The SLA-2812DN uses a CS-mount interface and is designed for 1/3" image sensors. It is compatible with Hanwha box cameras that accept CS-mount lenses and provide a DC-type auto iris driver circuit, as well as CS-mount box cameras from other manufacturers with a matching 1/3" sensor format.
Q: What is the difference between a DC-type and video-type auto iris, and why does it matter?
A: A DC-type auto iris is driven by a voltage signal from the camera body. A video-type iris includes its own amplifier and reads the video signal directly. The SLA-2812DN uses DC-type control, so the host camera must have a DC iris driver output. Using it with a video-type iris camera port will result in incorrect exposure behavior.
Q: Will the SLA-2812DN work on a C-mount camera?
A: Not directly. C-mount and CS-mount differ by a 5mm flange-back distance. A CS-to-C adapter ring allows a CS-mount lens to be used on a C-mount camera body; however, the reverse (C-mount lens on a CS-mount body) is not possible without focus issues. Verify mount type on your camera before ordering.
Q: Can this lens be used with a 1/2" or larger sensor camera?
A: The SLA-2812DN image circle is designed for a 1/3" sensor. On a 1/2" or larger sensor, vignetting (darkening or cropping at the image edges) is likely, particularly at wider focal settings. For larger sensors, select a lens rated for that sensor format.
Q: Does the varifocal range on the SLA-2812DN mean it is motorized?
A: No. Varifocal means the focal length is manually adjustable within the 2.8–12mm range. You set the zoom and focus during installation. It is not a motorized or remote-focus lens — adjustment requires physical access to the lens.
The SLA-2812DN is the lens I reach for when a project calls for a Hanwha box camera in an indoor commercial environment and the final field of view is not locked in at design time. The 2.8–12mm varifocal range means the installer can tune coverage on the wall without a return visit — and the F1.3 DC auto iris handles the light variation in lobbies and retail floors without manual intervention after commissioning.
Technical Highlights:
- 2.8–12mm Varifocal: Roughly a 4× focal range in a single lens — covers a wide entrance view at 2.8mm and pulls in to a tighter lane or counter shot at 12mm. One SKU handles most interior scenarios.
- F1.3 Maximum Aperture: F1.3 is a fast aperture for a varifocal lens, which helps in lower-light interior conditions where the auto iris needs to open up without the image going noisy.
- DC-Type Auto Iris: The camera body drives the iris actuator directly. This is the most common iris control type in the Hanwha box-camera line, so integration is straightforward — but it is not universal across all manufacturers.
Deployment Considerations:
- Confirm your box camera has a DC iris driver output before ordering. If the camera only supports video-type iris or has no iris driver, this lens will not auto-expose correctly and you will need a fixed-iris or video-type lens instead.
- The 1/3" image circle is a hard constraint. Do not pair the SLA-2812DN with a camera body carrying a sensor larger than 1/3" — vignetting will degrade the image, especially at wider focal settings near 2.8mm.
This lens is best positioned for indoor Hanwha box-camera installs — retail floors, corridors, and commercial lobbies — where the integrator needs flexibility to dial in the field of view on-site without carrying a kit of fixed lenses to the job.
