Hanwha SLA-M2890PN 3MP CS-Mount Varifocal Lens

Hanwha SLA-M2890PN 3MP CS-Mount Varifocal Lens

The Hanwha SLA-M2890PN is a varifocal lens designed for 1/2.8" 3-megapixel sensors deployed in professional surveillance systems. The 2.8–9mm focal range allows you to adjust field of view without swapping hardware — a significant practical advantage when site conditions change or coverage requirements shift after initial deployment. CS-mount compatibility ensures integration with a broad range of camera platforms across the Hanwha IP camera lineup and other professional surveillance vendors.

Key Features

• Varifocal 2.8–9mm focal length: The 3.2x zoom range lets you optimize coverage for both wide-area monitoring (2.8mm end) and tighter object recognition (9mm end) using a single lens. This flexibility reduces the need for multiple fixed-focal-length lenses in mixed deployment scenarios.
• P-Iris motorized auto iris: Electronically controlled iris adjusts aperture in response to changing light levels, maintaining consistent depth of field and resolution across the frame. This is especially valuable in scenes with significant ambient light variation — storefronts, parking lots, building entrances — where a fixed iris would either blow out highlights or underexpose shadows.
• IR correction filter: Optimizes optical transmission in the near-infrared spectrum, reducing color shift and chromatic aberration when the camera switches to infrared illumination at night. The result is sharper, more color-accurate footage even during low-light operation without visible purple fringing.
• Day/Night capability: Supports day/night operation without additional optical filters; the camera's internal IR-cut filter controls the spectral shift. Simplifies mechanical design and reduces cost compared to motorized filter turret systems.
• 1/2.8" sensor format: Optimized for 3MP resolution, delivering approximately 6.4 µm pixel pitch — large enough to handle low-light scenes reasonably well while keeping sensor cost and camera body size moderate.
• CS-Mount interface: Industry-standard C-mount mechanical and electrical interface ensures compatibility with outdoor IP cameras, low-light cameras, and compact camera platforms without special adapters.

Integration & Compatibility

The SLA-M2890PN integrates with any CS-mount IP camera platform featuring a 1/2.8" sensor and 3MP resolution. Verify lens compatibility before ordering by confirming your camera's mount type (C-mount vs. CS-mount) and sensor size; a mismatch will result in soft focus or vignetting. For deployment guidance on lens selection, sensor size, and focal-length planning across multi-camera systems, see the lens and coverage guide.

When to Choose a Different Model

If your deployment requires a wider field of view at the wide end, consider a lower-range varifocal (e.g., 2.7–5.4mm) in the Hanwha lens family. Conversely, if you need longer telephoto reach for vehicle plate recognition or perimeter scanning, a 5–50mm varifocal or fixed telephoto lens may be more appropriate. Confirm sensor format compatibility with your camera platform before purchase.

Frequently Asked Questions

Q: Is the SLA-M2890PN compatible with all CS-mount IP cameras?

A: No. Compatibility requires a CS-mount camera body with a 1/2.8" sensor and 3MP resolution. C-mount and other sensor formats will not achieve proper focus or image coverage. Confirm your camera specifications before ordering.

Q: Can I use the SLA-M2890PN on a fixed-iris camera?

A: Yes, mechanically. However, you will not benefit from the P-Iris auto iris feature — the motorized iris will not function. A camera with motorized iris support is required to unlock the depth-of-field and lighting-adaptation benefits.

Q: What is the difference between CS-mount and C-mount?

A: CS-mount has a shorter back focal distance (12.5mm) than C-mount (17.5mm). Using a CS-mount lens on a C-mount camera will result in focus beyond the sensor plane. A C-mount lens on a CS-mount camera may not focus at all. Always verify your camera's mount specification.

Q: Does the SLA-M2890PN include an IR-cut filter mechanism?

A: No. The lens includes an IR correction filter to optimize performance during IR illumination. The camera body must provide the motorized IR-cut filter (day/night switching). Confirm your camera platform includes this feature.

Q: What is the optical format (sensor size) of this lens?

A: The lens is optimized for 1/2.8" sensors at 3MP resolution. This format is common in professional surveillance cameras but less common in consumer webcams. Confirm your camera's optical format before ordering.

Marty Allison

Perspective based on aggregated IP Security Depot and affiliated engineering team experience.

The SLA-M2890PN (often searched as SLA M2890PN) solves a real problem: the need for a single lens that handles both wide-area coverage and closer detail without operator intervention. The 2.8–9mm varifocal range covers roughly 110° at the wide end and 28° at the telephoto end — enough spread to handle retail floors, warehouse aisles, and parking lot perimeters with a single optic. Pair this with the P-Iris motorized iris and IR correction, and you have a lens that adapts to changing light without sacrificing sharpness.

Technical Highlights:

• P-Iris motorized iris: Maintains consistent depth of field across 10–15 EV range. In mixed-light scenes (bright windows and dark corners in the same frame), the motorized iris prevents either blown-out or underexposed zones that would plague a fixed-iris lens.
• IR correction filter: Reduces color shift in nighttime IR mode by optimizing lens transmission at 850nm. The result is noticeably cleaner IR footage — important if you're relying on license-plate or facial recognition in 24/7 deployments.
• 3.2x zoom ratio (2.8–9mm): Bridges the gap between fixed wide (2.8mm) and fixed medium (9mm) lenses. One lens eliminates inventory complexity and reduces the chance of mounting the wrong focal length to a camera body.

Deployment Considerations:

• Confirm your camera body supports motorized iris control; if it doesn't, you lose the adaptive depth-of-field benefit and must fall back on sensor-level exposure compensation.
• CS-mount socket on your camera is non-negotiable — a C-mount camera will not focus with this lens. This is the most common integration mistake with varifocal lenses.
• The 1/2.8" format sits between compact surveillance sensors (1/3") and larger cinema optics (1") — good cost-to-performance balance but not ideal for extreme low-light or high-zoom scenarios where larger sensors excel.

Use this lens in retail, warehouse, or light-industrial monitoring where you need flexible zoom but can't justify motorized zoom optics or multi-camera coverage. The P-Iris and IR correction make it reliable in 24/7 mixed-light environments, and the 2.8–9mm range keeps installation simple.