Camera matching for still images

[fudini]

This "Set Extensions" by Jarrod Davis DVD is for lightwave:

http://www.desktopimages.com/VFX1.shtml

He goes through a process of matching camera angles where he lines up cubes and so forth but its still trial and error and a few educated guesses. I like it because he doesn't hide the trial and error process.

The book "Matchmoving" by Tim Dobbert also begins with an exercise of manually matching a still image but thats in Maya. He still makes a lot of good suggestions that are applicable to any 3D app.

If your reference was taken with a digital Cam often the lens info is embedded in the exif info of the original file which you can view in irfan view or something.


f.

[CaptainObvious]

I'll look into that. Thanks. :)

[CaptainObvious]

I found a rather excellent Lightwave plugin for this sort of thing. It's even free!

http://f23.aaa.livedoor.jp/~fisjunk/plugin/plugin.php?id=11&p=1&c=3&t=Layout&v=4#f (http://f23.aaa.livedoor.jp/%7Efisjunk/plugin/plugin.php?id=11&p=1&c=3&t=Layout&v=4#f)



Now I just need a good tutorial for matching lighting and getting good shadows. ;)

[fudini]

Cool, thanks!!

Did you figure out how to use it?

It says (in Google Japanese translation):
"In order from the sample point for Object to agree to Background Image, camera parameter is adjusted.
Sample 6 samples or more please take the point.
Minimum of 2 as for the points please make sure not to ride same plane.
When [pointosetsuto] is used, only the point which belongs to point set is indicated.
With the left click with movement (with the right click sample point cancellation) of the sample point and the Alt + Shift + left drug zoom of view is possible with movement and the Alt + Shift + right drug of view."

hmm...

Come to think of it, I think Worley has a plug that has something to do with Camera matching too!

Lets see if I can remember the name ...

Ok, here it is. Its called "Camera Match". Doh! :rolleyes:
http://www.worley.com/taft/taft_cameramatch.html

f.

[CaptainObvious]

Using the plugin is very simple. Create some low-resolution proxy geometry with important (and accurate!) measuring points. Set up the camera so it's not too far off from the backdrop.

Add the plugin to LW's interface somehow (keyboard shortcut, a menu, whatever), and activate it. In the window that pops up, add the backdrop in one of the pulldowns.

Then, simply drag the vertices so they align with the backdrop. I haven't experimented all *that* much with it yet, but I think that verts you don't touch aren't considered in the calculation. So if you have vertices for stuff that isn't visible on the backdrop, just ignore them.

Then click "ok" or whatever, and the plugin does the rest.



It basically works the same way as Worley's plugin, except it's supposedly better, and it's free...

[fudini]

Wow!
Thanks for that, great stuff:applause:

Another thing I've been thinking of trying for a locked off shot.
1. Set up the camera on a tripod
2. Shoot the locked off shot.
3. Afterwards pan the camera away so as to have enough info to solve using conventional matchmove software and just use the first frame info.

But this is even better/faster and works with high-rez stills.

Cheers,

f.

[CaptainObvious]

Wow!
Thanks for that, great stuff:bounce:

Another thing I've been thinking of trying for a locked off shot.
1. Set up the camera on a tripod
2. Shoot the locked off shot.
3. Afterwards pan the camera away so as to have enough info to solve using conventional matchmove software and just use the first frame info.

But this is even better/faster and works with high-rez stills.

Cheers,

f.
Unfortunately, you don't always have control over that part of the workflow. It wasn't me behind the camera. Otherwise that's exactly what I would've done. But... this method is even better!

[jussing]

3. Afterwards pan the camera away so as to have enough info to solve using conventional matchmove software and just use the first frame info.I think panning would just give you a flat point cloud, you'd need to dolly or crane the camera to get the parallax needed to solve a matchmove.

But a 3D app like Max has a camera matching feature that will work if you estimate the measures of the scene.

Cheers,
- Jonas

[fudini]

You're right!

I should have said
"3. Afterwards move the camera so as to have enough info to solve using conventional matchmove software and just use the first frame info."

f.

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