Avoiding Parallax

[James Marshall (Hogan1953)]

Looking for some help here. Where should I be putting my camera to film my students' swings in order to avoid parallax as much as it is possible? At the moment Down the Line I'm putting the camera at about hand height pointing through the golfer's hands towards the target. From face-on, again at about hand/belt height pointing at the golfers belt buckle. From the rear, belt high right through the middle of the trouser pockets. Any good or should it be somewhere else? Thanks for any suggestions.

 

[Jared Willerson]

I think I read a thread on this by Brian in here before, if you do a search, I'm sure you'll find something that can help you.

 

[Jim Kobylinski]

i feel the best way is to point the camera parallel or perpendicular to the plane line and have the hands be the center of the video but far enough away to get the whole swing in the view.

 

[Michael Finney]

there is NO way to completely avoid parallax with a 2D camera....the methods described above are probably the best attempts......you may have to go out and buy 3D motion analyzer like biovision to really see what's going on....fairly expensive

 

[birdie_man]

DTL is a tough one....

What do you want to see with the camera centered on the hands Jim? (DTL I mean)

Perp. for face on (like Jim said):
http://homepage.mac.com/brianmanzella/.Movies/mikestlocdriver05front.mov

Notice the box. That's you you make sure it's lined up right.

 

[rave154]

Depends

Hogan,

it depends on which "bit" of the body you wish to check on the camera, since the only part of the "picture" that the camera captures that isnt affected by parallax/perspective problems...is the exact centre of the picture, both vertically centre and horizontally centre.

So, if you wanted to check say..the position of the left arm at the top of the backswing... you have to position the camera such that the left arm appears in the exact centre of the picture ( note that, you also have to choose which part of the left arm you want in the centre as its impossible to get the whole left in the centre). Checking this particular aspect ( left arm at the top ) would require having the camera fairly high up ( as high as the left arm is when at the top of the backswing) because if you leave the camera down at waist level with the lense looking UP at the left arm..the view will be distorted with regard to angles etc.