Comparing LED and incandescent light bulb output

[Michael Chare]

I have just bought my first mains powered LED light bulb, as you can now get reasonably powerful one for less that £10. (An Integral 10.5w bulb from Amazon at £8.55)

So before I made the purchase I found that the bulb gave out 820 lumens which is a bit more than one might expect to get from a 60 watt bulb.

Fitting the bulb to a pendant ceiling light, it is apparent that all the light is emitted downwards and sideways, but not upwards so the ceiling remains dark and there is no reflected light into the room.

AIUI lumens is a measure of the total light output, but if you start taking direction into account the comparison between LED and incandescent light bulbs is more complex than I first thought.

[Brian Gaff]

Yes I thinkI mentioned this some time ago. It is the same on the smaller ones often fitted into illuminated magnifiers apparently. The light is apparently whiter, but has restrictionas it does not cover the whole of the viewing area as well as a bulb used to. Its alreight people making direct replacements for bulbs but they do not take into account that the large angle of light output might be a factor in the design of the application. Brian