An alternative approach to RED ISO

[Björn Benckert]

Pretty much the way I am thinking now.
Thanks for validating the approach, and more interesting insights, master Phil.



That's an easy answer. If you lower the ISO, you know that you are not changing the amount of light that hits the sensor, and you are not changing the quality of the image, as it is exposed properly already. You already know there is no degradation in quality by moving a stop down from 800. You are just showing the director how it will look once "pulled", or printed down, or however you want to call it.

Let's make it more interesting. Same scenario of above, but now the directors tells you that the image is too dark overall. What do you do?

Iso is a number for digital gain. Digital gain = noise. So the real question is, how much noise do you allow your image to have. If you dont have a problem with higher noise levels then what your current iso provide, then you can just bring up the iso if the director ask for a brighter image. If you dont accept higher noise levels then you need to change some other parameter, the amount of light, iris or exposure time.

 

[Daniel Stilling]

Let's make it more interesting. Same scenario of above, but now the directors tells you that the image is too dark overall. What do you do?

Well, in that case i would think about increasing the ISO first. This very much depends on how the scene is lit, how large the dark areas are. If, to my previous experience, I asses that the image would get too noisy, I would probably pump a little more light from my key, even that it would be compromising my balance with the practicals. The last thing I would do would be to change my shutter speed. It would change the motion feel and that would be a lot worse to me than a little more noise in the picture. Now that is all for Dragon. I don't have a Helium yet, but I have a feeling that raising the ISO a stop or so would cause no issue noise wise.
I feel that if you tie yourself to one ISO value only, you are limiting yourself in what you can do...

 

[Daniel Stilling]

Here's an example:

I shot this film for Dior, and the director did not want any kind of light. none whatsoever. That's his prerogative and I wanted to give this challenge a try. Mostly exterior, but with a couple of interiors, and also end of day tragic hour..
So, that was my biggest limiting factor. On this I shot with ISO's from 250 to 2000. If I had just stayed with 800, I would have been limited even more, and maybe even not been able to pull off some of the shots...
https://www.youtube.com/watch?v=_ycppFdA3Sc

 

[Alberto Guglielmi]

Iso is a number for digital gain. Digital gain = noise. So the real question is, how much noise do you allow your image to have. If you dont have a problem with higher noise levels then what your current iso provide, then you can just bring up the iso if the director ask for a brighter image. If you dont accept higher noise levels then you need to change some other parameter, the amount of light, iris or exposure time.

I like that approach. I still prefer to think of film, as it is more sexy for me than digital gain....

Here's an example:

I shot this film for Dior, and the director did not want any kind of light. none whatsoever. That's his prerogative and I wanted to give this challenge a try. Mostly exterior, but with a couple of interiors, and also end of day tragic hour..
So, that was my biggest limiting factor. On this I shot with ISO's from 250 to 2000. If I had just stayed with 800, I would have been limited even more, and maybe even not been able to pull off some of the shots...
https://www.youtube.com/watch?v=_ycppFdA3Sc

Very beautiful work. I love it Daniel.
I am not saying not to use ISO to change things. I am simply approaching it differently.
Rather than thinking that changing ISO I am changing the sensitivity of the sensor to the light, I am now looking at it as a fixed ISO (800) that I can maneuver in post to what I need/want, but I see the results before hand while I shoot. I am not committing to an ISO, but I am committing to an amount of light in the sensor. Your approach on the "dark" scenario is the same I have. I now consider that my choice is either to give less light to the sensor (upping ISO and therefore adding noise), or add more light if I want to proper expose it for base ISO without changing the sensor optimal center. Just looking at a different approach. Neither is right or wrong. Or better, the right one is the one you choose and communicate with your client about...