Quote Originally Posted by Kino View Post

Carbon arcs went out when sound came in; you couldn't have the strike and the hum/splatter of a big arc during a quiet scene. This lead to a push to use incandescent lights which, in turn, caused an eruption of various "studio styles" that came about in the early years of talkies as cinematographers reacted and tried to deal with the loss of blue-rich light sources the filmstocks preferred.

Yes, panchromatic was available, but was still red-weak, which is (as you say) the bias toward which radiated energy emitted from early incandescent luminaries, so they had an urgent problem on their hands that had to be dealt with post-haste.

Auteur theorists will no doubt rise in revolt, but I think like the Novelle Vague owed its revolutionary styles of production to a basic technical break-through in lightweight location equipment, so to did Hollwood Studio "styles" emerge in their fight to regain enough illumination to continue their film factory output.

No doubt a few bright individuals made good use of this technical problem to craft a creative response and continue it as a signature, but I highly doubt the various "styles" would have been so pronounced had there been no technical crisis.

Man did I wander off topic, sorry!

There are some scientific articles written by Peter Mole on the development of movie lights here (you might have seen them):


I got John Anton's book "Painting with Light". It gives very comprehensive overview of the luminaries used in that Era. Most interestingly, it mentioned in somewhere about the use of lens diffusion disk made of glass to be placed in front of the fresnel lens...this is something different from wire scrim we use nowsdays and it was used for close-up face shot especially actresses. Obviously glass diffusion disk does not alter the directionality & spread of the beam and its effect is different from putting a silk/spun glass/frost on the barndoors or scrim frame that gaffers use these days.