BenQ TH685i vs Optoma UHD35STx
 BenQ TH685iMSRP $899 |  $1,299 | |
|---|---|---|
| Key differences | ||
| White light output | 3,500 lm ANSI | — |
| Native resolution | 1080p (1920 × 1080) | — |
| Throw ratio | 1.13–1.46:1 | 0.5:1 |
| Lowest input lag | 8.3 msDerived | 4.2 msDerived |
| Fan noise | Normal 35 dB(A) · Eco 29 dB(A) | Normal 28 dB(A) · Eco 24 dB(A) |
| Price | MSRP $899 | $1,299 |
| Room fit | ||
| Distance to screen | 2.5–3.2 m | 1.1 m |
| Brightness | ||
| Rated brightness | 3,500 lmDerived | — |
| White light output | 3,500 lm ANSI | — |
| Claimed brightness (non-standard) | — | 3,600 lm |
| Brightness uniformity | — | 80% |
| Display system | ||
| Imaging technology | DLP | DLP |
| Chip / panel diagonal | 0.48 in | 0.65 in |
| On-screen resolution | 1080p (1920 × 1080)Derived | 4K UHD (3840 × 2160)Derived |
| Native resolution | 1080p (1920 × 1080) | — |
| Native aspect | 16:9Derived | 16:9Derived |
| Pixel shift | — | XPR 4-way |
| Addressable resolution | — | 4K UHD (3840 × 2160) |
| Colour wheel segments | 6 | — |
| Colour wheel speed | 2× | — |
| Contrast | ||
| Dynamic contrast | 10,000:1 | 1,000,000:1 |
| Dynamic contrast method | — | Light-source dimming |
| Manual iris | — | No |
| Colour | ||
| Colour gamut | Rec. 709 95% coverage | — |
| Colour bit depth (per channel) | 10 bit | — |
| Gamma / EOTF presets | 2.2, 2.4, + 2.6 | 2.2, 2.4 |
| Colour temperature presets | Native, + Custom | + D93, + D65, + D55, Native |
| HDR | ||
| HDR formats | HDR10, HLG | HDR10, HLG |
| Tone mapping | — | Adjustable |
| Calibration | ||
| Colour management (CMS) | 6-axis | 6-axis |
| Picture mode memories | 2 | — |
| Picture certifications | — | ISF |
| 3D | ||
| 3D | Yes | Yes |
| 3D formats | Frame packing, Side-by-side, Top-bottom, Frame sequential | Frame packing, Side-by-side, Top-bottom, Frame sequential |
| Light source | ||
| Light source | Lamp | Lamp |
| Lamp power | 245 W | 240 W |
| Replacement lamp | 5J.JL805.001 | — |
| Light-source life | 4,000 h normal · 10,000 h eco · 15,000 h super eco · 8,000 h dynamic | 4,000 h max · 10,000 h eco · 15,000 h dynamic |
| Warm-up time | About 30 s | — |
| Cool-down time | — | 90 s |
| Optics | ||
| Throw ratio | 1.13–1.46:1 | 0.5:1 |
| Image size | 30–300 in | 36.43–301 in |
| Projection offset | 105% | 116% |
| Zoom | Optical | None |
| Zoom ratio | 1.3×Derived | — |
| Focal length | 11.9–15.5 mm | 7.51 mm |
| Aperture (f-number) | 1.94–2.07 | 2.8 |
| Focus | Manual | Manual |
| Autofocus | — | No |
| Vertical lens shift | ±5% | None |
| Vertical keystone | 40° | 40° |
| Horizontal keystone | — | 40° |
| Auto keystone | Yes | — |
| Grid warp | — | Yes |
| Motion & gaming | ||
| Max input refresh | 1080p: 240 Hz · 4K UHD: 60 Hz | 1080p: 240 Hz · 4K UHD: 60 Hz |
| Max refresh at 1080p | 240 HzDerived | 240 HzDerived |
| Max refresh at 4K | 60 HzDerived | 60 HzDerived |
| Input lag | 1080p: 60 Hz 16.7 ms · 120 Hz 8.3 ms · 4K UHD: 60 Hz 33.4 ms | 1080p: 240 Hz 4.2 ms · 4K UHD: 60 Hz 16.9 ms |
| Lowest input lag | 8.3 msDerived | 4.2 msDerived |
| Input lag at 4K 60 Hz | 33.4 msDerived | 16.9 msDerived |
| Inputs & control | ||
| HDMI inputs | HDMI 2.0 (ARC, HDCP 2.2) · HDMI 2.0 (HDCP 2.2, internal) | 2 × HDMI 2.0 |
| HDMI inputs (count) | 1Derived | 2Derived |
| Newest HDMI version | HDMI 2.0Derived | HDMI 2.0Derived |
| Other video inputs | + VGA, + Component | None |
| Max input resolution | 4K UHD | DCI 4K |
| Audio inputs | 3.5 mm | — |
| USB media playback | — | No |
| Control ports | RS-232 | RS-232, + 12 V trigger |
| Horizontal scan | 15–102 kHz | 31–135 kHz |
| Vertical scan | 23–120 Hz | 24–120 Hz |
| Smart platform | ||
| Wi-Fi | Wi-Fi 5 | — |
| Bluetooth | 4.2 | — |
| Smart platform | Android TV | — |
| OS version | 9 | — |
| Google-certified | Yes | — |
| Chipset | Amlogic S905Y2 | — |
| RAM | 2 GB | — |
| Storage | 16 GB | — |
| Security updates until | 31 Dec 2024 | — |
| Netflix | No | — |
| Casting | Chromecast built-in | — |
| Audio | ||
| Speaker power | 5 W | 10 W |
| Speakers | 1 | 1 |
| Layout | Mono | Mono |
| Audio outputs | 3.5 mm, + HDMI ARC | 3.5 mm, + Optical |
| HDMI audio return | ARCDerived | NoneDerived |
| Physical & installation | ||
| Dimensions (W × D × H) | 312 × 225 × 110 mm | 315 × 270 × 118 mm |
| Weight | 2,790 g | 3,500 g |
| Colours | White | White |
| Orientations | Table, Ceiling, Rear | Table, Ceiling, Rear |
| Ceiling mount | M4 | M4, screws ≥ 10 mm |
| Environment & power | ||
| Operating temperature | 0–40°C | 5–40°C |
| Operating humidity | 10–90%RH | 10–85%RH |
| Altitude | 3,000 m · high-altitude mode | 3,000 m · high-altitude mode |
| Power draw | Max 340 W · Normal 297 W · Eco 206 W | Max 320 W · Normal 320 W · Eco 220 W |
| Standby | Up to 0.5 W | 0.5 W |
| Mains input | 100–240 V · 50/60 Hz | 100–240 V · 50/60 Hz |
| Noise | ||
| Fan noise | Normal 35 dB(A) · Eco 29 dB(A) | Normal 28 dB(A) · Eco 24 dB(A) |
| Safety & compliance | ||
| Risk group | RG2 | RG2 |
| Marks | — | CE, FCC |
| Support & ownership | ||
| Warranty | 3 yr (light source 1 yr or 2,000 h) | 1 yr (light source 3 mo) |
| User manual | https://esupportdownload.benq.com/esupport/PROJECTOR/UserManual/TH685i/TH685i_UM_EN_210913182301.pdf | https://region-resource.optoma.com/products/import/Documents/5ba3a4c4-9910-4450-86ed-8d571c21506b.pdf |
| Spare parts | Lamp 5J.JL805.001 | — |
| In the box | ||
| In the box | Power cord, Remote, Remote batteries, + Quick start guide, + Warranty card, + VGA cable, + Streaming dongle | Power cord, Remote, Remote batteries, + User manual |
| Remote | IR · voice | Backlit |