Grey Card

[techie98]

about grey cards (

I was just wondering (rather then having it held on a easel, or setting up another light so its lit flat) can you just hold the card and shoot it in your key exposure in white light (5 feet every roll), and for the scenes where your under exposed/over or in mixed lighting conditions will it provide the timer with a good basis of what to consider normal.

Thank You

 

[David Mullen ASC]

You can have someone hold it -- it helps actually since it also gives the timer a skintone reference -- but it needs to be in white light and frontally (flatly) lit. If your key light is white and frontal, then you can use it, as long as you expose fully for it.

 

[techie98]

Just to clear something up, do you have to expose/light the card at the same f stop as the scene? Can you get away with properly exposing it at one stop and then having the next scene maybe a stop higher or lower (with the addition of extra lights) but still of proper exposure.

If I light the card at a 2.8 and expose for that average, and then my scene after the shot card is at a f 4 (exposed properly for the 4) will the timer see that scene as a stop under. Or since there both properly exposed with the 4 come out as 18% relectance.

THanks Again

 

[David Mullen ASC]

You don't need to light the card to the same stop as the scene unless the scene is part of the shot with the card, which some people do -- put the card in the foreground and the set lighting in the background. Then you do need to light the card to the level you plan on shooting the scene at.

Otherwise, if the card and face fill the frame, it can be at any stop as long as you expose for it the way you want, at the rating you are giving the stock, etc. Although since there are some contrast changes at different stops, you don't want to go extreme, light a card to f/11 and shoot the scene at f/2.

The lab people, the colorists, etc. can't really tell whether you shot a card at f/4 and the scene at f/2.8 if in both cases, this was the correct exposure, just like if you shot a card lit for f/4 and then shot a second card lit for f/2.8, and exposed for how they were lit, they would look the same to the colorist (other than depth of field.)

A card lit and shot at f/4 and then a following, separate scene lit and shot at f/2.8 doesn't mean that the scene is a stop underexposed. It's exposed correctly, just like the card was. For all the colorist knows, you actually lit the card to f/2.8 and shot it at f/2.8.