AF123MA2 Projector Lens 1.02–1.72:1 for 4 Leli Models: RL-10KU, RL-85U, RL-K1, RL-KU1200

AF123MA2 is a medium-to-long-throw lens for RELLE engineering projectors, with a 1.02–1.72:1 throw ratio and lens shift. It is compatible with 4 models from 1 model series. This guide presents the lens specifications, installation distances, compatible model list, and replacement key points in one place.

1. Lens Specifications

Lens shift capability is the key differentiator of this lens. Its 36% horizontal and 15% vertical shift ranges allow the projector to be installed off the screen's horizontal center axis and the image to be brought back into position using lens shift, without relying on keystone correction. Keystone correction comes at a cost—every adjustment step reduces the effective pixel count and softens text edges. In professional installations, never use keystone correction when lens shift can solve the alignment issue; this is a fundamental principle of image quality.

2. Calculating Installation Distance from Throw Ratio

Throw ratio is the ratio of the installation distance to the image width. This zoom lens (1.02–1.72:1) supports a range of installation distances for each image size, and the lens can focus anywhere within the applicable range.

These distances represent the clear space from the front surface of the lens to the screen, excluding the space required for cooling and cable connections at the rear of the projector. The values are calculated for a 16:10 aspect ratio; actual values are subject to on-site measurement and the manual.

Image quality differs at both ends of the zoom range: near the short-throw end, the image is brighter and the edges are slightly softer; near the long-throw end, the edges are sharper and brightness is slightly lower. Where space permits, use the middle of the range. After installation, first find the sharpest setting on the focus ring, then fine-tune the lens shift—adjusting both variables at once makes precise alignment difficult.

3. Compatible Models (4 Models, RELLE)

The following table is ordered by model production date, from newest to oldest. It lists each model's resolution, brightness, and zoom ratio for the factory-standard lens, enabling quick identification based on project requirements.

The zoom ratio shown is the zoom factor of the model's original standard lens (upper limit ÷ lower limit of the factory throw-ratio range), not the zoom range of the lens featured in this article.

Common Characteristics of These Models

The original standard lenses for the 4 models mostly have throw ratios in the 1.42-2.64:1 range. The 1.02–1.72:1 ratio of the model discussed here effectively changes the focal-length range, allowing different image sizes at the same projection distance—this is the direct reason for replacing the lens. Full lens shift capability is retained, so the image can still be aligned after the focal range is adjusted.

4. Three Checks Before Replacement

• Verify the panel size. Panel specifications for this model are not yet included in our database. Please send us a photo of the projector's nameplate for confirmation.
• Check the interface and locking mechanism. Interfaces are generally interchangeable within the same-generation platform, but the locking latch position differs between generations. If the image appears skewed or the edges are not sharp after installation, the latch is usually not fully engaged; this is generally not a lens defect.
• Allow for shift margin in the installation. The lens shift range provides installation margin, but edge image quality declines at the limits. Actual use is therefore recommended to remain within 70% of the rated values.

For reliable confirmation of whether a model not listed here is compatible, send us photos of the projector's nameplate and original lens. Models on the same-generation platform often share interfaces, but ordering based only on a similar model designation carries unnecessary risk.