Lens Apeture?

[TangMotorPictures]

Okay ASA of DVX is 640 ASA. Right?

If you had a light meter, and it said to put it an apeture at F 4.8, would that be equivalent if you shot it with Film?

If so, what kind of film stock would it be most similar to? Anyone do any test yet? Barry????

I hear Cinematographer say that if a film stock is 600 ASA, they treat it like 500. Meaning that treat it slower so that more light can hit the film. Which means more saturated colors? Which typically means, prettier pictures.

Now, since DV doesn't really have emulsion like film, is saturation non-existence in digi world?

So is opening the apeture all the way open, the better way?

 

[Barry_Green]

Re: Lens Apeture?

This is a complex situation. I go into it in detail in the new book, but let me say: it isn't as easy as all that. The ASA rating depends on the overall light level in the scene. The camera responds like a 400ASA speed in lower light level conditions, and like a 1000ASA camera under bright-light conditions! The exposure curve is not linear.

Over most of the curve, for most purposes, it responds at approximately 640, but that's not a hard and fast rule -- it all depends on where in the exposure range the camera is. Furthermore it depends on if you're in interlaced or progressive mode: interlaced is typically a stop faster than progressive under all circumstances, but not linearly.

I've come to the conclusion that trying to use an external light meter with the DVX is folly -- you're much, much, much better off using an external monitor and the zebras.

For saturation, underexposing somewhat can lead to much more saturated colors (like reversal film, whereas with negative film the opposite is true, overexposing negative film can increase saturation). Of course there are several things you can do to increase saturation -- on the DVD I show a "Magical Projectile" look called "Color Reversal" which results in extraordinarily saturated colors... so it can most definitely be done.