Does more light always mean more heat?
I’m trying to illuminate an extremely small dark space, but bringing my lights closer to the subject risks damaging what I’m photographing. (Using Apunture 600d LEDs with Fresnel heads).
I’d like to stick with continuous light if possible, since I’m also pixel-shifting for resolution in this series.
LEDs emit very little UV or IR which is what damages illuminated subjects. The safe illumination distance on the most powerful LED film lights from Arri is only about 3ft, which is only double the safe distance for heat around the entire housing. (This is based on 8hr continuous illumination).
By comparison for a similar output Tungsten head you’re looking at distances of 3m and for HMI heads as much as 8m.
These are high end motion picture lamps so it’s possible they have better spectrum control than Apurture lamps, but they’re also emitting substantially more light so I can’t see something like a 600D being an issue as far as IR or UV emission.
So unless your “small dark space” is literally the size of a wardrobe LED heads should pose no heat risk to your subject.
My small dark space is the inside of a 300 year old Violin. The apunture lights can heat the varnish to unsafe levels in around 30 seconds.