Compositing and photographing miniatures with Live Action

[Carlos M Jimenez]

When using miniatures how do you account for the field of view to match when you are shooting actors on green screen who will later be composited into.

In other words, if I have a 50mm lens at 8k to shoot live action, do I shoot the miniature at 8k with a 50mm lens? SO the backgrounds match? ANd what happens if I want to add acmera moviemnet? How do you account for that in the miniature? I assume motion control. If that is the case do I shoot everything in motion control?

I thought wider lenses made the miniature have verisimilitude. Do I have to shoot it at 1:1? And there are a few more layers. What happens if I down res the recording format to 5k 2:1 and shoot the miniatures that way.

 

Thanks. Any advice will help.

 

 

 

 

[Karim D. Ghantous]

From what little I know, this is what you have to do: measure the distance to the live action subject. Say, it's 6'. And the vertical FOV, for arguments' sake, is exactly head-to-toe.

So, how do you imitate that with a miniature? Well, you use the scale of the miniature. So, if the live action actor is 6' tall, and you are 6' away from him, and if the miniature is 6" tall,  then you put the camera 6" away from it. Then match the FOV. 

That is all I know and even here I might be wrong, because I've never done it. But, you should be able to test this via experiment.

[David Mullen ASC]

Yes you have to scale the distance and lens height, etc. Plus stop down a lot…

But the focal length should be the same. However if you feel you might need to have room to realign the background plate, meaning you might need to zoom in first, then it would help to shoot on a slightly shorter focal length with frame lines for cropping to the matching focal length.

[David Mullen ASC]

23 hours ago, Karim D. Ghantous said:

From what little I know, this is what you have to do: measure the distance to the live action subject. Say, it's 6'. And the vertical FOV, for arguments' sake, is exactly head-to-toe.

So, how do you imitate that with a miniature? Well, you use the scale of the miniature. So, if the live action actor is 6' tall, and you are 6' away from him, and if the miniature is 6" tall,  then you put the camera 6" away from it. Then match the FOV. 

Not to mention that if the 6’ tall live action actor was shot with a camera 6’ in the air, now the camera lens has to be 6” high for the miniature… you see why snorkel lenses, probe lenses, etc. sometimes have to used when the lens position for the miniature is somewhere a normal camera and lens can’t fit.

[Doug Palmer]

6 hours ago, David Mullen ASC said:

Not to mention that if the 6’ tall live action actor was shot with a camera 6’ in the air, now the camera lens has to be 6” high for the miniature… you see why snorkel lenses, probe lenses, etc. sometimes have to used when the lens position for the miniature is somewhere a normal camera and lens can’t fit.

Not too much about miniature shoooting on this forum, I always find it fascinating.  Snorkel lenses tend to be expensive.  It's usually possible to dig the camera down low enough, or possibly use a mirror arrangement.  Lens on small stop, so probably long exposures needed.  Carlos, I can see that if you down-res the format it could help the green-screen combination. But I don't know as I have only used film.  Maybe others can help.