On 27/03/2014 11:12, Mike Tomlinson wrote:
In article , Martin Brown |||newspam|||
@nezumi.demon.co.uk writes

This really is impressive because only the low pressure sodium vapour
lamp and the microwave pumped sulphur lamp are in that league.

I recently was in a shopping mall lit by (I think) metal halide lamps
(big white bulb, probably E40 cap).

Some of those fittings had been retrofitted with large spiral CFLs and I
was impressed with their brightness and colour rendition. They were so
bright it was difficult to look at them directly.

http://www.energynowinc.com/cms/?q=S...n_Replacements

This seems to me to be a suitable case for using CFL rather than LED as
a replacement.

There are already LED units with better efficacy although worse CRI I
don't know what the price in bulk or availability is like. There are
some in use at the Wetherby service station seating area on the A1.

http://www.gogreenledinternational.c...-220w-hid.html

(not a recommendation - no experience of these units)

--
Regards,
Martin Brown