Candela and lumens are just two different ways of measuring light output.
As I understand it, Candela is based on the level of highest light intensity in the beam while lumens actually measures the entire light output of the device.
Neither measurement tells you a lot about whether you will get a tight beam or a diffuse beam, that has more to do with the design of the light.
All else being equal, a large smooth reflector has the potential to provide a tighter beam while a small reflector, or a reflector that is textured will tend to provide a more diffuse beam.
Inside a house, where walls and ceilings are typically light colors, you get a lot of scatter. You can often illuminate an entire room surprisingly well by shining the light at the ceiling in the middle of the room.
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