Re: Meters and more
Mark Weingartner, ASC
Doesn’t matter if I know the offset - same as shooting greenscreens or bluescreens for the last thirty years
Only if you have the camera with you on the scout
By the way, if you want to walk down a hallway and see what the light is doing between fixtures, that is really easy to do with an incident light meter… can’t do it reliably with a still camera or a motion picture camera without another person as a model or some ungainly attempt to hold a gray card steady and shoot it with your camera without pumping into things…
You make some dangerous and incorrect assumptions here. Yes they are similarly designed chips. (Film stock acetate or polyester subtrates were all similar too)
However, the actual dyes used in the sensor masks differ from camera mfr to camera mfr , the gains applied to different channels at different settings varies, and the de-mosaicing software from camera to camera along with the viewing transform to get it into the monitor vary WILDLY.)
My meters, on the other hand, are the same all the time all the time all the time - at least since I switched to solid state ones that are a bit more resistant to dropping.
(I still have my main and backup Spectra Pros and Candelas squirreled away which should survive an EMP event)
Look, I used polarioid B&Ws as full frame exposure metering devices for many years and I started using DSLRs to help in determining exposure as early as Batman Begins and Rush Hour 3 (both shot on film)
I continue to do so, though I always have to figure out offsets since the still camera’s default viewing de-bayer is rarely anything like what my motion picture camera is going to do…
Your mileage may vary - if you are shooting documentary or doc-style narrative work and you arrive with your camera you have your camera right there to use for exposure… but those of us who have to evaluate locations and prep to light sets days and weeks ahead of a production camera showing up the route forward with the fewest variables is a an incident meter and a reflected light meter of known calibration and performance - it is the standard.
Each camera we use (and I have used most upper end models of most manufacturers as well as lots of still cameras for vfx work) has its own idiosyncrasies and part of what I charge for is knowing how to correlate my exposure meter tools to the camera’s actual sensitivity, not what the manufacturer said it would be - same as with film.
Nothing other than the actual camera you are using will be totally accurate - so if I wont be totally accurate - I will generally use a meter (with offsets I understand if necessary)
That gets us going on lighting.
Before we shoot? we use the actual picture to set the stop - of course! but why make it harder than it has to be?
We are not luddites - we are experienced professional narrative and commercial directors of photography who have to get a job done - need to be able to communicate with our gaffers over the phone etc. meters are really good for doing what they do. Still cameras are less good at that - even though I always have one or two or three with me.
None of this is theory or speculation on my part.
If I’m lighting a one day spot I might only pull out the meter to look at the sweep we are lighting or a greenscreen we are lighting while the camera is still being built… and spend the rest of the day looking at a scope - sometimes with a DIT or sometimes without - it depends what all we are doing on set versus whether I am just feeding a VFX hopper with uncolored material.
For you young whipper-snappers out there aspiring to working bigger and bigger jobs, the three things I strongly recommend you learn how to use are
an incident light meter, a spot meter, and a camera operator.
All three will save you time, and one of them will allow you to stick with your director a bit more - a useful place to be.
With the meters you need to learn how to interpret the data.
With the operator you need to learn how to communicate your wishes, manage your operator(s) effectively, and work out the relationship between yourself, the Director, and the operators… and the sooner you start honing all of these skills the less intimidating the “big jobs” will be.
Mark Weingartner, ASC