Fair warning, some of the Dahua Camera's are quite blurry close range, so pay careful attention to the min focus distance
2549:
2.8 mm: 1.7 m (5.58 ft)
3.6 mm: 2.6 m (8.53 ft)
3449:
Close Focus Distance
2.8 mm: 2.0 m (6.56 ft)
3.6 mm: 3.5 m (11.48 ft)