And the Lord said, "Let there be light!"...

[Pete Askew]

Yes but how much exactly...

And what colour?

I'll follow this up with a bit more information later. But I thought this was an interesting comparison following on from the discussion about light meters elsewhere. In the first image there is a Sekonic Studio Master sitting alongside the L-608. Both are capable of measuring incident light (and direct illumination) but the L-608 can also measure reflected light using the built-in spot meter and flash and flash / ambient. Sekonic still make an analogue meter based on the Studio Master

Below this is an old colour temperature meter from Gossen. Still works perfectly although I confess I now use a digital meter when I need to (it saves looking things up in tables). I'll compare the two when I get back to Germany as it's in the studio. The manual for it is great though!

http://www.butkus.org/chinon/flashes_meters/gossen/gossen.htm

 

[Hamish Gill]

Do you know, I've never come across a colour meter!
Shall look forward to hearing more!

 

[Pete Askew]

http://www.robertwhite.co.uk/product.asp?P_ID=2070&PT_ID=179

Mostly these days you either use auto-white balance or calibrate the session to the lighting with a white card or control patch but there are times when you want to know the temperature so you be precise with later corrections. With film the purpose is to either adjust the lighting to match the spectral characteristics of the emulsion or to work out what filter to employ on the camera. The Sixticolor does just that. You measure the the colour of the light using the cell on the reverse of the meter (pressing the button at the top unlocks the needle). You then set the scale lower marker on the type of film you are using and then read back from the measured temperature to the scales that tell you the filter number etc that you require to correct the lighting for the film.

The digital meters also provide this sort of information but allow for detailed analysis of the lighting within a scene (they are used more probably in cinematography than stills these days I guess except in technical applications). I'll try to write something more extensive next week.