Illumination mcd for flashlight bulbs ?

mcd's,

I believe that the mCd is dependent on the reflector, and how narrow the beam is, so it can't be determined with just the lamp itself. The lamp catalogs give the ratings in candlepower.

Go to Don's lighting pages for more info,

I don't give any specific photometric numbers of any incandescent flashlight lamps there.

Most "miniature lamps" have output stated in "spherical candlepower" or "MSCP", one of which is 4-pi lumens. Assuming a straight or only slightly curved filament, candela in the plane perpendicular to the filament axis is higher by a ratio close to 4/pi.

As for candela of a flashlight: Yes it is true, this is heavily a function of a flashlight's optics. However, this is limited to frontal area of the reflector (or lens) times the surface brightness of the filament in candela per square centimeter, which I consider very unlikely to exceed 3,300 (half the figure for a 3300 Kelvin blackbody) - much less for lamps with a vacuum (require lower filament temperature), such as PR-2, 14, and most others under about a watt or both under 3 watts and drawing less than about .35 amp unless noted as having a premium gas fill or being halogen.

I have major doubts about the "candlepower" claims of most of those supposedly million and multimillion candlepower handheld spotlights.

- Don Klipstein ( snipped-for-privacy@misty.com)