— Projector Throw · Home Cinema
Home theatre — 120-inch 16:9 screen, 4 m room
Problem. A dedicated home theatre with 4 m of throw distance needs a projector that hits a 120-inch 16:9 screen without zoom at the optical limit.
Answer. At 4 m throw to a 2.66 m wide image, the required throw ratio is around 1.5 — comfortably within the zoom range of most premium 4K HDR home projectors. The planner shows ratio, lumens required for ambient conditions and the lens shift envelope.
02 / In depth
How this preset reads — the engineering view.
Home theatre projection is a constraint-stack: screen size you want, throw distance you have, ambient light you can't fully control, and zoom envelope of the projector class you can afford. This preset locks the first two and lets the calculator reveal the constraint surface around them.
120-inch diagonal at 16:9 is 2.66 m wide. At 4 m throw distance, the required throw ratio is approximately 1.5. That's a comfortable mid-zoom for premium home projectors — JVC NZ-series, Sony VPL-XW series, Epson LS series and similar. The calculator will let you adjust either throw or screen size to see how the ratio drifts.
Lumens to target: a treated, light-controlled cinema room is the ANSI-friendly end (~16 fL on screen, 1500–2000 lumens at the screen for a 1.0-gain matte white). A multi-purpose room with partial light control needs roughly double. The calculator shows the recommended brightness window against your selected ambient assumption.
What this preset doesn't decide for you: native vs pixel-shifted 4K, laser vs lamp service life, HDR tone-mapping behaviour, and the gain / acoustic-transparency choice for the screen itself. Those are not throw decisions — they are program-material and room-treatment decisions.
What this preset deliberately does not solve
- Brightness target assumes a fully treated room; multi-purpose spaces need 1.5–2× more lumens.
- Screen gain (1.0 matte vs 1.3 silver vs acoustic-transparent) shifts brightness math.
- Lens shift envelope is projector-specific and is not modelled here.
How this preset differs from its siblings
The boardroom-100-inch sibling preset uses 16:10 aspect (Mac/Windows source content), moderate ambient light (4000+ lumens minimum), and a slightly shorter throw to a smaller screen — those decisions all derive from corporate AV constraints. This preset sits in the opposite zone: 16:9 (film content), a fully treated dark room (lumens can drop to 1500-2000) and a longer throw to a larger screen. The throw-ratio number (~1.5 vs ~1.4) looks similar but the engineering brief around it is unrelated.
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Brief us on the project — with this configuration.
Presets are a typology starting point. The brief wizard captures the room geometry, programme and constraints we need to translate this configuration into a real design.