What should one do when in a countinuos shot the light changes drastically? For example, when moving from interiors to exteriors or the opposite. Should one use the Iris button to stop down or up accordingly, or is there something else more appropriate to do?
Hmmm... I suppose it would depend a lot on what "look" you are going for.
Personally, I'd avoid it. If, for instance, I was doing a follow from someone indoors to out, I'd set the exposure for the interior and let it blow out upon exit...then cut to a new angle, properly exposed, and go on from there.
And I'd never do a continuous from outdoors to in, unless the actor immediately "turned on the lights" in the interior.
Letting auto iris handle things might very well look like a transition of sorts...which may or may not be what you want.
On the other hand, if this is not for a set piece, and you mean for something like catching a Congressman in a motel room with two cheerleaders and a bag of marshmallows, then following as he dashes for his car, auto iris might be the way to go. Or split the exposure difference, and adjust later in post.
Calito, I would do the opposite. I would adjust the exposure for outside, then I would check the setting for inside, then I would lean more towards the exposure of the outside shoot the scene. The footage inside will be darker of course, being that you set the exposure leaning more for the outside. You can lighten the inside shots in post production, but I would still try to bring some of that sun light into the interiors via windows, bounce cards or if you have them HMIs.
i would just think of a creative way to have a cut/separation between the two environments so i didnt have to do it.. ..i mean how vital is it to the story that it be shot in that particualr way where you are presented with this problem?
or contol one environment ..likely by daylight correcting and adding more light inside. to allow for common exposure and color temp between the two during the crossover shot.
I just did this shot. We needed to Steadicam from a line outside a theater to inside pass concession stand then up 3 filghts of stairs to an open hatch. Dang Steadicam !!
Well, shoot at a time of day where the outside light levels are low & and the same color to the inside.
Overcast is a good substitute for sweet light too. Color correct for inside.
The trick is it's always the first take or the last, so work the talent before the light is right and you'll be golden.
Another trick is Tungsten balance the camera, have a 85nd.9 over the lens & have a PA remove it at the right time as you pass thru the door.