Can anyone, er, cast any light on whether it's possible to translate lux to lumens? I don't think it is, so it's a bit difficult to compare this to anything else!
From Wiki:
Differences between lumens and lux
The difference between the units lumen and lux is that the lux takes into account the area over which the luminous flux is spread. A flux of 1000 lumens, concentrated into an area of one square metre, lights up that square metre with an illuminance of 1000 lux. The same 1000 lumens, spread out over ten square metres, produces a dimmer illuminance of only 100 lux. Mathematically, 1 lx = 1 lm/m2.
A single fluorescent light fixture with an output of 12000 lumens might light a residential kitchen with an illuminance of 500 lux. To light a factory floor with area dozens of times that of the kitchen would require dozens of such fixtures. Lighting a larger area to the same level of lux requires a greater number of lumens.
ENDS
To add to the confusion, if the above fluorescent fitting could somehow be converted so as to throw a precise beam, then the equation would go in the other direction, but this would be relative to the distance from the light source
As far as lamps go, I repeat what is on my ledcaplamps, dont buy anything unless you have seen it perform underground.
My avatar is a poor likeness.