Hot spots (2 replies)
As a student filmmaker, my biggest battle with using consumer digital products (formerly the T2i, currently the Sony a6000) is the poor latitude. For example, with a film I'm currently trying to stage lighting for, the proper exposure for the desk lamp in the frame (indoor scene) is F22, whereas the person in frame (about 1.5 feet from the lamp) is all the way down at 1.8. Even when I totally flood the area with light, the lamp is still an overexposed hot spot. An obvious fix is to replace the lamp with a low wattage bulb, but considering the desired look for the scene is that the actor and environment is only being lit by the one desk lamp in frame, that becomes problematic for wide shots.
Do you have any recommendations, or is this the sort of situation where I should swap out the brighter bulb with the dimmer one when I can, and just accept that in some shots I'm going to need to live with the hot spot?
That's just a problem with the camera and there is not much you can do about it if you need the bulb itself to light your subject. Yes, you can use a low wattage bulb, probably very low wattage, but then the shot might look artificial.
Does the desk lamp have a lamp shade? If so, you could gaff some ND gel, scrim material, or even black wrap (depending on how much light you want to cut) on the inside of the lampshade, but only on the side that faces the camera. Assuming the scene is blocked so that the side of the light that faces the camera is is opposite from the side that light the actor, you'll have successfully cut the hot spot while lighting the actor.
Alternatively, a method that I believe I have read Mr. Deakins uses to boost the light of practicals in scenes is hiding another, brighter bulb behind the practical. In this case, you could try to rig up a bare bulb in a socket behind your fixture (say a 60 or 100 watt, depending on your scene) and then a 15 watt in your fixture. Provided the desk lamp is large enough to hide a secondary socket behind it, you're golden. However, you may have a hard time adding diffusion to the bare bulb and hiding it in the wide, so I'd recommend moving the bare bulb out of frame and add some diffusion for the close up, to try to mimic the quality of the light coming out of the desk lamp.