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View Full Version : Please help: Matching my camera perspective to that of a photo



ajaxrobinson
03-23-2007, 09:46 AM
Hello, :help:

I am trying to match the perspective of a video I am trying to put 3d into. It's very simple, I just want the 3d logo on top of this metal bridge, which the camera pans up too.

The trouble is I cannot figure out how to change the vertical perspective so that the logo matches.

Please can someone explain to me how I can change this or what I'm doing wrong.

Attached are 2 images. The first one is current perspective, the second one shows how I need the perspective.

Any suggestions will be very appreciated

Thanks for reading

stib
03-23-2007, 11:06 AM
See how the log is getting smaller towards the top? There's too much perspective there, which mean that your camera lens length is too short (zoom factor is too low) and it's too close. Zoom in and track out and your perspective will decrease, making those verticals more parallel.

Lens length, or in LW terms Zoom Factor is the crucial key to matching perspective, it will never work unless you get it right (the best way to do that is of course to make notes when the shot is being shot, if you can).

ajaxrobinson
03-23-2007, 11:26 AM
Great!

Thanks for the help. I was playing with it for ages and it just kept on getting more and more distorted. Thanks for pointing me in the right direction.

It's not completely accurate (I have to make it just right to work with the pan upwards before this frame) but you can tell it's better after just 2 mins of adjusting thanks to your advice.

:) Thanks again :thumbsup: