SC331 Projector Lens 1.26–1.95:1 for 2 Christie Engineering Projectors: 4K7-HS, 4K10-HS

The SC331 is a medium- to long-throw lens for 0.65/0.66/0.67 panels (Christie), with a 1.26–1.95:1 throw ratio and lens shift. It is compatible with 2 projector models in 1 model series. This guide consolidates the lens specifications, installation distances, model compatibility list, and replacement considerations.

1. Lens Specifications

Lens shift is the key differentiator of this lens. The 110% horizontal and 50% vertical shift ranges allow the projector to be installed off the screen’s centerline, with lens shift bringing the image back into alignment without requiring keystone correction. Keystone correction comes at a cost—each adjustment reduces the effective pixel count and can blur text edges. In professional installations, avoid keystone correction whenever lens shift can resolve the alignment issue; protecting image quality is essential.

2. Calculating Installation Distance from Throw Ratio

The throw ratio is the ratio of installation distance to image width. This lens has a 1.26–1.95:1 zoom range, so a given image size corresponds to a range of installation distances, and the lens can be focused at any position within that range.

These figures represent the clear distance from the front lens element to the screen and do not allow for rear housing ventilation or cable connection space. They are calculated for a 16:10 image; actual distances must be confirmed through on-site measurements and the manual.

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

3. Compatible Models (2 Models, Christie)

The table below is arranged by model production date from newest to oldest and lists each model’s resolution, brightness, and factory lens zoom ratio for quick selection according to project requirements.

Common Features of These Models

The factory-standard lens throw ratios for these 2 models are mostly listed as Depends on the lens. The 1.26–1.95:1 ratio of the model featured in this article effectively adjusts the focal range, allowing the same projection distance to produce different image sizes—this is the direct reason for replacing the lens. Full lens-shift capability is retained, allowing the image to remain aligned after the focal range is adjusted.

4. Three Checks Before Replacement

• Match the panel and resolution. This model is compatible with a 0.67-inch panel. Projectors with a different panel size or resolution may exhibit different projection performance; checking the projector nameplate before installation provides the most reliable match.
• Check the interface and locking mechanism. Interfaces are generally compatible within the same platform generation, but the position of the locking clip varies between generations. If the image appears skewed or the edges are not sharp after installation, the lock is usually not fully engaged rather than the lens itself being faulty.
• Factor lens-shift margin into the installation. The shift range provides installation flexibility, but edge image quality declines when the shift is pushed to its limits. For regular use, keep the shift within 70% of the specified values.

To determine whether a model not on the list is compatible, send us a photo of the projector nameplate and the original lens for verification—platforms of the same generation often share interfaces, but ordering based solely on a similar model designation carries unnecessary risk.