reverse info of camera distance & angle from still frame?

[vonkuttenberg]

hello guys, is there any way how to count reversely from vanishing points & horizont a distance of the camera & camera angle (& lense)? i am going to shoot some greenscreen stuff for this picture ... thnx for info

i would like to know where to position the camera and what angle.

i am wondering about that when the vertical lines are straight up, that means that the camera is flatlings ahaed (0°), when they meet upwards mean that the angle is <0° (camera looking down) and vice versa >0°? but is there any way how to count more precisely?

 

[alloneword]

Hi Vonkuttenberg,

Download a fisheye perspective grid from the web into photoshop, superimpose your house image, lower the opacity to see through it, position and scale the image until the house's square edges best fit the grid (ignoring the bowing).

The ground grid lines (at right angles to each other) that are perpendicular to the horizon will meet under your camera's position.

Plot the relative positions and house footprint on a piece of graph paper. Draw two diverging lines emanating from your camera ptn spaced widely enough to contain the house's footprint. The angle between those lines is, roughly, your field of view.

Match that to your camera lens's FOV/focal length data.

Note: FOV is sometimes measured horizontally instead of diagonally. A diagonal FOV measurement changes with aspect ratio.

Easy.

 

[vonkuttenberg]

thanks a lot, ill try

 

[Paul Hudson]

Try the pcam app for the iphone