D-flash 40, Bare bulb guide number

[Olof B]

Hello.

According to the manual the D-40 Flash has guide number 40 and 33 when working in Normal setting and Wide.

But what is the bare bulb able to produce for output?

Best regards,
Olof

 

[polypal]

My guess is you will loose about half the output of the D40 when used without a reflector.
That gives a gn of 15-20.

For studio flash heads the capacity is quoted as Wattsecond.
The effective light output depends on the reflector and diffussor you choose.