Canon RS-SL04UL Ultra Long Zoom Lens: Compatible with 17 Models Including REALiS 4K5020Z, 4K6020Z

Canon Original Lens RS-SL04UL Ultra Long Zoom is a genuine optical accessory for Canon installation projectors, belonging to the long throw category, with a throw ratio of 3.55-6.94:1. The original compatibility list covers 17 models; before installation, simply verify against the projector model and panel size — no adapter rings needed. The value of an original lens isn't in a few extra rows of numbers on a spec sheet, but in the fact that it is calibrated at the factory to the optical path and mount of that series of projector bodies: once mounted, the image circle, edge illumination, and focus travel are all at their design values, so you don't need keystone correction to compensate for image quality.

1. Lens Specifications

The above specifications are subject to the original manufacturer's specifications. For mechanical dimensions, flange focal distance, and mount type that are not shown in the spec table, please verify with us against the projector model — ordering based on model similarity alone carries the risk of incompatibility.

2. Converting Throw Ratio to Installation Distance

Throw ratio is the ratio of installation distance to image width. This original lens is a zoom lens (3.55-6.94:1), so the same image size corresponds to a range of distances; as long as installation falls within this range, focus can be achieved.

The above figures are the clear distance from the lens front to the screen, excluding rear ventilation and cabling space behind the projector body. Calculated for 16:10 aspect ratio; actual values are subject to on-site measurement and the original manufacturer's manual.

Image quality differs at the two ends of the zoom range: toward the near end the image is brighter with slightly softer edges; toward the far end the edges are sharper with slightly reduced brightness. Where site conditions permit, it is recommended to land in the middle of the range; after installation, first find the sharpest position on the focus ring, then fine-tune the shift.

3. Compatible Models (17)

The table below is taken from the original compatibility list; brightness and resolution are filled in from the model database, with "—" where unavailable, without speculation.

To determine whether models outside the list can be used, please send us photos of the projector nameplate and the existing lens for verification — same-generation platforms often share mounts, but ordering based on model similarity is a risk not worth taking.

Throw Ratios Across Model Series

The same RS-SL04UL Ultra Long Zoom mounted on the following series does not have the same nominal throw ratio; selection should be based on the actual series of the projector body.

4. Three Things to Confirm Before Replacement

• Confirm the projector chip and resolution. Original lenses are designed for specific panel sizes; with a different panel specification, the image circle cannot cover it, resulting in vignetting or edge light loss after installation.
• Calculate the installation distance first. This lens has a nominal throw ratio of 3.55-6.94:1; use the table in Section 2 to map it to your site dimensions. Prime lenses have no margin, and even with zoom you should leave 10–20 cm at both ends.
• Check the mount and locking. Original lenses are calibrated to the mount of that series of projector bodies; after installation you must hear the lock click into place. Image skew and soft edges are mostly due to incomplete locking, not a problem with the lens itself.

If unsure, take one photo each of the projector nameplate and the existing lens nameplate and send them to us — verification against the actual hardware is the most reliable approach.