Optoma ZH420 vs Optoma ZH451ST
 MSRP $1,799 | $1,499 | |
|---|---|---|
| Key differences | ||
| White light output | — | 4,200 lm ISO |
| Throw ratio | 1.12–1.47:1 | 0.5:1 |
| Lowest input lag | 8.6 msDerived | 8.4 msDerived |
| Fan noise | Max 31 dB(A) · Normal 29 dB(A) | Normal 36 dB(A) · Eco 29 dB(A) |
| Price | MSRP $1,799 | $1,499 |
| Room fit | ||
| Distance to screen | 2.5–3.3 m | 1.1 m |
| Brightness | ||
| Rated brightness | — | 4,200 lmDerived |
| White light output | — | 4,200 lm ISO |
| Claimed brightness (non-standard) | 4,300 lm | — |
| Brightness uniformity | 75% | 75% |
| Display system | ||
| Imaging technology | DLP | DLP |
| Chip / panel diagonal | 0.65 in | — |
| On-screen resolution | 1080p (1920 × 1080)Derived | 1080p (1920 × 1080)Derived |
| Native resolution | 1080p (1920 × 1080) | 1080p (1920 × 1080) |
| Native aspect | 16:9Derived | 16:9Derived |
| Contrast | ||
| Dynamic contrast | 2,000,000:1 | 2,000,000:1 |
| Colour | ||
| Colour bit depth (per channel) | — | 10 bit |
| Gamma / EOTF presets | 2.2, 2.4 | 2.2, 2.4 |
| HDR | ||
| HDR formats | HDR10, HLG | HDR10, HLG |
| Calibration | ||
| Colour management (CMS) | 6-axis | 6-axis |
| Picture certifications | — | ISF, Filmmaker Mode |
| 3D | ||
| 3D | Yes | Yes |
| 3D formats | + Frame packing, Side-by-side, Top-bottom, Frame sequential | Side-by-side, Top-bottom, Frame sequential |
| 3D glasses sync | DLP-Link | DLP-Link |
| Light source | ||
| Light source | Laser (phosphor) | Laser (phosphor) |
| Emitter | — | Blue laser + phosphor |
| Light engine | — | DuraCore |
| Light-source life | Up to 30,000 h max | 30,000 h |
| Light output control | Steps | Steps |
| Constant brightness mode | — | Yes |
| Cool-down time | 90 s | 90 s |
| Optics | ||
| Throw ratio | 1.12–1.47:1 | 0.5:1 |
| Image size | 31–322 in | 30–300 in |
| Projection offset | 116% | 116% |
| Zoom | Optical | Digital |
| Zoom ratio | 1.31×Derived | — |
| Focal length | 16.9–21.61 mm | 7.51 mm |
| Aperture (f-number) | 2.43–2.78 | 2.8 |
| Focus | Manual | Manual |
| Autofocus | No | No |
| Vertical lens shift | None | — |
| Vertical keystone | 30° | 15° |
| Horizontal keystone | 30° | 15° |
| Auto keystone | Yes | — |
| Corner correction | 4-corner | 4-corner |
| Motion & gaming | ||
| Max input refresh | 1080p: 120 Hz | — |
| Max refresh at 1080p | 120 HzDerived | — |
| Input lag | 1080p: 60 Hz 17 ms · 120 Hz 8.6 ms · 4K UHD: 60 Hz 17 ms | About 1080p: 60 Hz 16.7 ms · 120 Hz 8.4 ms · 4K UHD: 60 Hz 16.7 ms |
| Lowest input lag | 8.6 msDerived | 8.4 msDerived |
| Input lag at 4K 60 Hz | 17 msDerived | 16.7 msDerived |
| Inputs & control | ||
| HDMI inputs | HDMI 2.0 · HDMI 2.0 (HDCP 2.2) | 2 × HDMI 2.0 |
| HDMI inputs (count) | 2Derived | 2Derived |
| Newest HDMI version | HDMI 2.0Derived | HDMI 2.0Derived |
| Other video inputs | — | VGA |
| Max input resolution | DCI 4K | 4K UHD |
| Control ports | RS-232 | RS-232, + Wired IR, + 12 V trigger |
| PJLink | — | Class 1 |
| Control-system drivers | Crestron, + AMX | Crestron |
| Horizontal scan | 15–140 kHz | 15–135 kHz |
| Vertical scan | 24–120 Hz | 24–120 Hz |
| Smart platform | ||
| Ethernet | Yes | Yes |
| Audio | ||
| Speaker power | 15 W | 15 W |
| Speakers | 1 | 1 |
| Layout | — | Mono |
| Audio outputs | 3.5 mm | — |
| HDMI audio return | NoneDerived | — |
| Physical & installation | ||
| Dimensions (W × D × H) | 274 × 216 × 114 mm | 274 × 216 × 114 mm |
| Weight | 3,000 g | 3,000 g |
| Orientations | + Table, + Ceiling, + Rear, Portrait, 360° | Portrait, 360° |
| Ceiling mount | M4, screws ≥ 10 mm | M4, 10 mm screws |
| Ingress protection | IP6X | IP6X |
| Environment & power | ||
| Operating temperature | 0–40°C | 0–40°C |
| Altitude | 2,500 m · high-altitude mode | 2,500 m · high-altitude mode |
| Power draw | Max 173 W · Eco 119 W | Max 170 W |
| Standby | Up to 0.5 W | Up to 0.5 W |
| Power supply | External adapter | External adapter |
| Mains input | 100–240 V · 50/60 Hz | 100–240 V · 50/60 Hz |
| DC input | 19 V | — |
| Noise | ||
| Fan noise | Max 31 dB(A) · Normal 29 dB(A) | Normal 36 dB(A) · Eco 29 dB(A) |
| Safety & compliance | ||
| Laser class | Class 1 | Class 1 |
| Risk group | RG2 | RG2 |
| Hazard distance | — | 1 m |
| FDA laser notice | Notice 57 | — |
| Marks | FCC | FCC |
| Support & ownership | ||
| Warranty | 3 yr (light source 5 yr or 12,000 h) | — |
| User manual | https://region-resource.optoma.com/products/import/Documents/02387d20-4b12-4d04-97e4-be316b803cf2.pdf | https://region-resource.optoma.com/products/documents/0NL94Q0vvVEJVe7dxQKlMzhtuURlT8FwUXNkLi8y.pdf |
| In the box | ||
| In the box | Power cord, Remote, Remote batteries, Quick start guide | Power cord, Remote, Remote batteries, Quick start guide |
| Remote | — | IR |