My measurement is pretty similar. But I think they are lower than rosemadder's because it is 2' bulbs. I now use 4' unit, but I haven't measured it yet.
I grow mostly species paphs, and the distance between the bulb and the top of the leaves are around 9-10" (or less for tall ones). The plants are getting about 1000 fc. But you might need to gradually increase the intensity. Last summer, some species did get heat stressed (I grow them in a grow tent, so heat is a problem even in Alaska).
I was using 15hours day (no seasonal change), but trying to reduce the day length, and it's now 14h/day (it costs me >$300/year for electricity, so I'm trying if they will grow ok with shorter day length).
Fixture: Hydrofarm FLT24 2-foot 4-bulb (pretty decent reflector)
Bulb: Hydrofarm AgroBrite 24W 6400K T5 HO, about 4 month old, with 15hr/day
Light meter: Gossen Ultra Pro (pretty high-end).
I made the measurements in the middle of the bulb (the brightest point).
With 4 bulbs:
595 fc @ 1 foot from the bulb
1165 fc @ 6 inches from the bulb
With 1 bulb:
205 fc @ 1 foot
595 fc @ 6 inches
As you probably know, lumen/W is slightly lower with 2' bulbs than 4' bulbs.
4': 5000lm/54W = 92.6lm/W
e.g. GE bulb:
General Electric: 48" T5 6500K High Output Starcoat, case of 10
2': 2000-2100lm/24W = 83.3-87.5lm/W
e.g. GE bulb is 2000lm:
General Electric: 24" T5 6500K High Output Starcoat
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