Optoma
ZK431ST-B
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Prices confirmed Nov 10, 2026 · we check every retailer daily
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The brightest 4K short throw we carry under $2,000, and one of the few projectors in the catalog that Optoma sells specifically for simulator use: it sits in Optoma's golf line with a dedicated Golf Sim colour mode rather than a generic preset you tune yourself. 4,100 lumens of 4K UHD (Optoma measures to ISO 21118, not ANSI) at a 0.496:1 throw, which puts a 100-inch image up from about 3.6 feet, per Optoma's manual. The DuraCore laser is rated 30,000 hours in eco mode; Optoma publishes no figure for its brighter mode. Input lag is published and low: about 17 ms at 4K/60 and 8.6 ms at 1080p/120 with Enhanced Gaming on, which also switches off keystone correction. Against the GT3900UHD at $1,499 it is $300 more for 100 extra lumens; the two share a cabinet, lens and manual, and both have a golf picture mode, so in most rooms the cheaper unit is enough. Optoma rates the GT3900UHD for screens up to 150 inches and this one to 300. The UHZ35ST, at $2,199, costs $400 more than this for 600 fewer lumens.
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How it stacks up against the closest alternatives.
Price history
What it’s cost, tracked daily.
We’ve tracked the ZK431ST-B at $1,799 every day since September 21, 2026. No change yet.
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Who this is for
Honest match per persona.
Good for
- Performance Seeker
4K with published low lag and a dedicated Golf Sim colour preset, so there is a sensible starting point without a calibration session. 4,100 lumens holds up in a room that is not fully blacked out.
- Space-Constrained
0.496:1 puts a 100-inch image up from about 3.6 feet, so it mounts close and stays out of the swing path. That is the tightest throw in the catalog, shared in 4K with the GT3900UHD, UHZ35ST and BenQ LK830ST.
- Family Setup
Bright enough for a room with ambient light and fast enough to game on, which is what a shared room actually gets used for between rounds.
Not for
- Cost-Effective Buyer
$1,799 when the GT3900UHD, on the same cabinet and lens, is 4K for $1,499. Its 100 extra lumens are not a value argument.
- Recreational Player
Fixed throw with no zoom means placement is decided for you. A zoom model is more forgiving if you are not building around it.
- Showroom
Mid-tier brightness. The ZK521ST-B or the LK936ST are what a showroom room wants.
Specifications
The numbers, plainly stated.
Image
| Resolution | 4K UHD (3840×2160); Optoma calls it True 4K UHD and names no chip |
| Lumens | 4,100 (ISO 21118) |
| Picture Mode | Golf Sim colour mode (preset) |
| Screen Size | 36–300 in (Optoma's spec table says 30–300, its feature list 36–300; the narrower range is used) |
Hardware
| Light Source | DuraCore laser (30,000 hours, eco) |
| Throw Ratio | 0.496:1 (short throw, fixed) |
| Lens | Fixed 0.496:1 short-throw lens (no zoom, no lens shift) |
| Keystone | ±15° with Smart Fit auto-alignment |
Performance
| Input Lag | 16.8 ms at 4K/60Hz and 8.6 ms at 1080p/120Hz with Enhanced Gaming on (Optoma's page says 16.7 ms at 4K/60; the manual's 16.8 is used); 33.5 ms at 4K/60 with it off. Keystone and four-corner correction are disabled in low-latency mode |
Room planner
See the Optoma ZK431ST-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.
Builds that include this product
Where this fits in a full simulator.
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