Native ISO

What this is about

Every sensor has a base sensitivity its designers optimised for, and the DP treats that number as the floor of the lighting plan. Move away from it and something gets paid: below native the highlight headroom shrinks, above it the shadows go grainy. On a night exterior the gap between ISO 800 and ISO 3200 decides whether the truck carries two units or twelve — so the number belongs in prep, not in a menu on the day.

A term only helps when everyone on set means the same thing by it — so what follows is how it is used, not a dictionary definition.

What runs differently here

In planning terms, that means:

• The manufacturer states the native ISO in the manual; it is a property of the sensor, not a preference in the menu.
• Two stops above native usually costs visible shadow noise long before it costs any detail in the highlights.
• Native ISO turns the DP's working stop into lamp wattage, which is why it lands in the budget conversation.

With TillyGen

TillyGen's equipment list keeps the native ISO next to the camera body, so lamp counts get planned from the sensitivity that will actually be shot.

Change one constraint and the consequences travel through the whole plan: affected shots are flagged, the call sheet is regenerated, and nobody keeps working from yesterday's version.