Animation: Exterior to Interior scene

[abywater]

I have a scene of a city building addition that is squeezed between to large buildings...i.e...not much direct sunlight entering the building. I have gotten some great images of both the exterior and interior, but, I have to use completely different settings for each image. I was wondering if anyone has had a similar situation and needed to create an animation that goes between two completely different render settings?! Any tips on the transition between exterior and interior would be great!

 

thanks!

 

Andrew

[Tommy L]

Treat them as seperate cameras. Any equipment, be it a celluloid, digicam or your eye, will adapt to the two seperate lighting conditions. Thats why you get indoor and outdoor film. Natural daytime light levels tend to be far greater than interior scenes, which are illuminated by either bounced light or artificial illumination.

If you watch a cheap tv show, like a DIY show, you'll see the camera struggle to change exposure as the crew walks into or out of a house.

For this reason, I would treat the int/ext shots as seperate camera tracks. Or do some comp work at the cusp. Its not something Ive had to do much. Be creative in the storyboarding and you'll be fine.

[Mechadus]

I have wound up doing probably 20 shots that go from interior to exterior or visa versa. Be aware - to do it well, thats a very expensive shot...

 

I have found from my experience that the easiest way to do it is to render 3 passes: Interior, Exterior, and animated doors (if applicable). The only real trick to it is to make sure that the important stuff (the cameras and sunlight) are in the same relative space in both scenes. Ill blot down my process really quick, and hopefully you will be able to use some of it:

 

My first step is to make the camera - Ill usually Xref the interior walls into the exterior scene, and place them wherever they need to be inside the building (the correct floor, then merge the Xref. Ill then make my camera, and fly it from where it needs to start into the building, using the Xref'd walls as a guide. Once I get my camera finished, Ill 'Save Selected' the camera, and interior walls in a scene all by itself.

 

I then Xref the Interior walls, and the camera back into my Interior scene, and line up the walls in the xref to the walls in the scene. Then merge the Xref, and delete the duplicate walls. The reason for this is to make absolutely sure that the camera is in the exact same relative space between the exterior, and interior cameras... Meaning if the camera enters the unit 2 feet from the edge of the door, and 5 feet from the interior floor, it will be 2 feet from the edge of the door, and 5 feet from the floor in the interior scene. Trust me, its almost impossible to get this right if you eyeball it.

 

From there, I render the exterior segment of the animation up to the point where the camera no longer sees the exterior walls. Put a plane with the Vray matte options set to -1 alpha contribution, and invisible to GI checked behind the door/window that the camera flys thru. Render the exterior as a .tga sequence or another file type that stores an alpha channel.

 

I then render the interior, from the first frame the camera sees into the interior, untill the end of the animation (thats the easy part)

 

Lastly, I render a pass of the doors opening (clients seem to like that), with EVERYTHING else in the scene set to Matte -1, so all that renders is the doors. (also render this as a .tga sequence)

 

Then, in After effects (you can do it in MAX too if you dont have any compositing software, but its complicated) I load my interior animation in a new comp, put my exterior animation over the top of the interior, so the interior animation shows thru the hole in the exterior. Then I drop my door pass over both other animations - you will have to adjust the start points of the interior and door pass, but if you do it right it should all line up pretty well.

 

Hopefully I didnt just confuse you more

 

-Nick Kropat

 

Sr 3D Artist

http://www.3dwebmedia.com

[Tommy L]

Andrew, I also always point questions about animations the following link, its very helpful tips from the people who make and view these movies day in day out:

 

http://www.cgarchitect.com/vb/22366-animation-mistakes-no-nos.html