Head-to-head
BenQ TH685P vs Optoma GT1080HDR
Side-by-side comparison of the BenQ TH685P and Optoma GT1080HDR: throw ratio, brightness, resolution, input lag and price — plus which one to buy.
Quick verdict
The BenQ TH685P and Optoma GT1080HDR are both standard-throw projectors in a similar price range. The Optoma GT1080HDR is brighter — 3,800 vs 3,500 lumens. The Optoma GT1080HDR can sit closer to the screen (throw ratio from 0.50 vs 1.13). Both cost about $799. For gaming, the BenQ TH685P has the lower input lag at 8.3 ms.
| Spec | BenQ TH685P | Optoma GT1080HDR |
|---|---|---|
| Throw ratio | 1.13–1.46 | 0.5 |
| Brightness | 3,500 lumens | 3,800 lumens |
| Resolution | 1080p | 1080p |
| HDR | Yes | Yes |
| Light source | lamp | lamp |
| Input lag | 8.3 ms | 16 ms |
| Price | ~$799 | ~$799 |
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Throw distance: BenQ TH685P vs Optoma GT1080HDR
How far each projector must sit from the screen for the same image size.
| Screen | BenQ TH685P | Optoma GT1080HDR |
|---|---|---|
| 80″ | 6.6–8.5 ft | 2.9 ft |
| 100″ | 8.2–10.6 ft | 3.6 ft |
| 120″ | 9.8–12.7 ft | 4.4 ft |
| 150″ | 12.3–15.9 ft | 5.4 ft |
Which should you buy?
- • Choose the Optoma GT1080HDR if a brighter picture in ambient light matters most.
- • Choose the BenQ TH685P for gaming — lower input lag means more responsive play.
Frequently asked questions
The Optoma GT1080HDR is brighter, rated at 3,800 lumens versus 3,500 lumens.
More comparisons
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