How to do interior matte?

Gabe Agoado · September 9, 2016

I would like to cover up some parts of a sci-fi set that aren't built in, and I want to use cgi only as a last resort. Matte paintings are typically for exteriors or very large interiors, does it make sense to shoot matte shots for a small-ish interior? The space is about 35 x 20 feet and the set walls are between 7-8 feet high, but the space itself has high ceilings that I want to cover with a matte.

These are some demo walls I made when I was considering doing the whole thing with miniatures and animation. I was going to make some more of them, cut them to fit the mattes and then shoot them in forced perspective and soft focus so they look believable. The second picture is a rough outline of a matte shot. The purple border is the boundary of the set, the camera will be slightly above where the actors are standing. The actual shot will be taken farther away, from ~25 feet away from the actors using a normal lens. The area shaded in red is part of walls/ceiling that I want to matte out, part of the ceiling actually slopes down on an angle between the camera and the actors.

Do I have to use glass or can I use acrylic?

dan kessler · September 9, 2016

What do you have against cgi? Happens to be a good way to add set extensions.

If you shoot miniatures, you have the focus, depth and lighting issues, and your models

must be painstakingly well-done to look convincing.

David Mullen ASC · September 9, 2016

I'm not sure if you are talking about glass in-camera matte paintings or foreground miniatures or just blacking parts of the frame to double expose something in the black areas, but the first two definitely require DEEP focus to look believable (since the near-to-camera painting or miniature has to look larger and farther than it actually is, so would fall into focus with the subject) and the third may or may not need to be in deep focus depending on if you want hard or soft/blurry matte lines.

Gabe Agoado · September 10, 2016

Sorry that I did not specify: This is what I thought I was referring to, but what I meant was more like building up the front half of a foreground model and gluing it to a piece of glass. Searching through threads on this forum I found one that referred to that as like a "3-D Matte". What you say makes sense though, I will probably be better off blacking out part of the frame and then double-exposing in post.

Dan, I don't have anything against cgi when used in the right application, I just have very little experience with it, and I think I would do a poor job. Imo a bad cgi job 9 times out of 10 will look worse than a bad practical effect, a la Sci-Fi channel original movies.

David Mullen ASC · September 10, 2016

http://scifiadventures.blogspot.com/2016/06/star-trek-ii-wrath-of-khan-directors.html

There's an example here of a set extended with a foreground miniature. It's not a bad idea but like I said, you need to stop down the lens so the the foreground looks more in focus like it would if it were large.