Optoma
ZK521ST-B
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Prices confirmed Nov 10, 2026 · we check every retailer daily
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5,000 lumens of 4K (Optoma measures to ISO 21118, not ANSI), built for simulator use, at a price that undercuts everything else in the catalog offering that brightness in 4K. The LG ProBeam BU53RG is rated 5,000 ANSI lumens at $3,799, the BenQ AK800ST 5,000 at $3,999 and the LK936ST 5,100 at $4,899; this costs $1,100 to $2,200 less. The figures are close but not measured the same way. The throw is 0.79:1 rather than 0.496:1: Optoma's manual puts a 100-inch image about 5.7 ft from the screen and a 150-inch about 8.6 ft (its datasheet says about 5.5 ft for 100 inches), where its 0.496:1 sibling, the ZK431ST-B, does 100 inches from 3.6 ft. Unlike that sibling it has vertical lens shift (a 106–125% offset: the overlap of Optoma's spec page, 104–125%, and its calculator data, 106–127%), so the mounting height has some give. Same DuraCore laser rated 30,000 hours in eco mode, the same published input lag (about 17 ms at 4K/60 with Enhanced Gaming on) and the same Golf Sim colour mode. This is the projector for a room with windows, or one big enough that brightness has to cover real screen area.
Compare with
How it stacks up against the closest alternatives.
Price history
What it’s cost, tracked daily.
We’ve tracked the ZK521ST-B at $2,699 every day since September 21, 2026. No change yet.
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Who this is for
Honest match per persona.
Good for
- Showroom
5,000 lumens of 4K on a 150-inch screen is what a showroom room is actually buying, and this reaches it $1,100 under the ProBeam and $2,200 under the LK936ST.
- Performance Seeker
4K with published low lag and a dedicated Golf Sim colour preset. Brightness that survives a room with windows in it.
- Family Setup
Bright enough that the room does not have to be dark to be usable, which matters more in a shared space than anywhere else.
Not for
- Cost-Effective Buyer
$2,699 for a projector. The GT2400HDR covers a light-controlled room at $1,299.
- Space-Constrained
0.79:1 throws from farther back than the 0.496:1 models — about 5.7 ft for a 100-inch image and 8.6 ft for 150 inches, per Optoma — so in a short room it hangs nearer the swing. In a tight room the ZK431ST-B is the same family at 0.496:1.
- Recreational Player
More brightness and more money than a casual room needs; the savings are better spent on the enclosure.
Specifications
The numbers, plainly stated.
Image
| Resolution | 4K UHD (3840×2160); Optoma's page says native 4K UHD but names no chip |
| Lumens | 5,000 (ISO 21118; Optoma's spec page now says 5,100, its datasheet and golf brochure 5,000; the lower figure is used) |
| Picture Mode | Golf Sim colour mode (preset) |
Hardware
| Light Source | DuraCore laser (30,000 hours, eco) |
| Throw Ratio | 0.79:1 (short throw) |
| Lens Shift | Vertical, 106–125% offset (Optoma's page says 104–125%, its calculator 106–127%; the overlap is used) |
| Lens | Golf Sim Short Throw Lens (Optoma's name), fixed 0.79:1 |
Performance
| Input Lag | 16.8 ms at 4K/60Hz with Enhanced Gaming on (manual; the page says 16.7), 33.5 ms with it off; 8.6 ms at 1080p/120Hz (the datasheet says 8.4; the higher is used) |
Requirements
| Throw Distance | 100 in at about 5.7 ft, 150 in at about 8.6 ft (Optoma's manual; its datasheet says about 5.5 ft for 100 in) |
Room planner
See the Optoma ZK521ST-B in your sim room.
The planner draws it to scale with your room and your screen: where it mounts, how far the lens sits from the screen, and whether your swing or your shadow crosses the light. It opens in a sample room; put in yours.
Same category, different tradeoff
Other projectors we considered.
PremiumBenQAK700STGolf-dedicated 4K laser — Auto Screen Fit, motorized zoom, Golf Mode, IP5X sealed. Suited to permanent builds.
Mid-tierBenQLK830ST4K laser short throw, 4,000 ANSI lumens, 0.496 throw. Optoma's ZK431ST-B covers the same throw for less.
Mid-tierBenQLH860ST1080p laser short throw at 5,000 ANSI lumens and a 0.5 throw: brighter than the 4K units at this throw, but 1080p.