matching Camera Perspective

# 1 16-05-2012 , 05:17 PM

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Hello all,

I've embarked on a little project which will eventually allow me to experiment with realflow. my only hurdle at the moment is my lack of understanding of perspective. I've made a maya scene (correct proportions modelled from an image)and i am trying to match a cg stationary camera to the scene. I thought this would be easy but I am really struggling to match a camera to the image. You will see from the attachment what I mean. This has been done successfully in CG before with a 50mm lens but I fail so far.

Any thoughts/approaches would be great!
Thanks J

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# 2 16-05-2012 , 05:29 PM

The thin red line
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I would go into the photos properties look under detail just to see if it has the focal lenght in there, then create a new pers camera and put the focal lenght to match the photo that would be my starting point............dave

Avatar Challenge Winner 2010

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# 3 16-05-2012 , 06:05 PM

The Nurb Herd
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what is the film back of the camera?

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# 4 16-05-2012 , 06:38 PM

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That was a cool scene in the original movie.

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# 5 17-05-2012 , 02:57 AM

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You need to know the film back, as well as the focal length. If the source is from an older film, it's safe to assume that it will have a 35mm film back. You then need to play with the focal length to match it up. This can be done easily using a 3d tracking package such as PFTrack.

Imagination is more important than knowledge.

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# 6 17-05-2012 , 09:12 AM

The Nurb Herd
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hmm, isn't that what i was getting at? sometimes its more helpful to have people think for themselves and learn rather than just chucking out answers.
if its just one frame, do it in maya.

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# 7 17-05-2012 , 05:25 PM

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Yeah I've been using a 35mm film back but I just can't line up my scene properly. Ive reshuffled/resized my models several times to no avail. It feels like i need to use a longer lens to pull forward the doors at the back and remove the ceiling but then I lose the angle on the skirting on the walls at the side. It is a stationary camera so i assumed i wouldnt be able to extract much data from something like pftrack.

thanks for your input guys. all my previous efforts with matchmoving have been based around automatically generated cameras from boujou calculated from moving cameras.
Please let me know if im heading in the righ direction with the angle. Any comments as always will be warmly welcomed

Thanks

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# 8 17-05-2012 , 05:27 PM

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That was a cool scene in the original movie.

Originally Posted by PixalZA

It certainly was. Kubrick was a genius.

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# 9 17-05-2012 , 06:04 PM

The Nurb Herd
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you could set the filmback in pftrack and use "pin" to orient a grid on the floor. you can turn on evaluate focal length or whatever its called. this will change the FL as you adjust the grid in camera.

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