Brightness Decisions

[Hammeritout]

Hey forum and roger sir

Sorry for the confused newbie question here,

How do i know how to choose the appropriate light fixture that will key my actor, making sure that it will be bright enough? I know this choice related to the ISO, speed and aperture on the camera, but lets assume generic cinema camera native ISO, 1/50 speed, and fast f/2.0 aperture. How do i know if an M8 HMI will do a certain job, or perhaps i need M18 or even brighter M40? Will 2K tungsten fresnel through 4×4 feet diffusion will be too much for interior night scene lighting long shot of living room with people or not? Is the Falcon Eyes rx 36tdx flex led will be bright enough for a situation or i need to rent a skypanel s120? I’m just giving examples but what I’m trying to figure out is what would be basics principles that i can follow to nail the right light brightness wise. Photometric sheet are good to compare between fixtures but im looking for more general guidelines and workflow to determine the appropriate light for a situation. how do i make my brightness decisions.

Hope the question was understandable

THANKS

Topic

[Roger Deakins]

Practice! You just have to judge the relationship with one small space to a larger one. That does take practice, and, possibly, a look at photometric charts. You might light the space in exactly the same way and then it is just multiples or larger lamps.

[Valou]

Hello !

Perhaps you’re already aware, but I’d recommend checking out the ‘Photometrics’ app by Arri and ‘Sidus Link’ by Aputure. These applications can be incredibly helpful as they provide detailed information on lux levels and power output for their respective lights, based on varying distances.

Hope that can help you 🙂

[LucaM]

Roger Deakins wrote:

You might light the space in exactly the same way and then it is just multiples or larger lamps.

This is a detail I still don’t completely understand looking at the lighting schemes you put on the site: I see rows of multiple lights but how do you calculate their number (experience apart of course) ? Is it on the base of lux emitted (at a given distance) by one lamp and the total surface you have to cover (to allow you the lens aperture you want to use) ?

[Author]

Replies