rudy@xxxxxxxxxxxxxxxxxxx writes:
<< Does any one know what color temperature the extra illuminator light bulbs
in the T28, T8, T10 macro flashes have ?
>>
Even high intensity incandescent bulbs have quite low color temperature
in the region of 2800K to 3200K, to avoid melting the filament! The efficacy
goes up with temperature but the life goes down more quickly. Normal home
lighting filament lamps have nominal lives of 2000hours. On the other hand
many high intensity (higher color temperature) projector bulbs only have
rated lives of some 20 - 30 hours. Halogen filled lamps extend the life of
higher temperature filaments somewhat by allowing the metal evaporated from
the filament to circulate and recondense on the filament rather than on the
envelope. The bulbs in the macro flashes appear to have a rather low color
temperature.
Trivia : Although halogen lamps have a higher efficacy than normal
incandescents the difference is quite marginal compared with the many fold
improvement from flourescents. Unfortunately, the huge popularity of halogen
lamps for home lighting has completely eliminated all the energy reduction
that has resulted from the introduction of electronically ballasted compact
flourescent lights in the home.
Since the ring flash strobe will generally completely overwhelm the
incandescent lamp unless the exposure runs much longer (like it might in the
OM2 on auto) it should not normally affect the exposed color temperature.
Regards,
Tim Hughes
>>Hi100@xxxxxxx<<
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|