Undistorting Lens Distortion from photos

[Nazgul]

What is the best method to undistort Lens Distortion from photos. eg wide angle

I have also shot a reference checkerd board grid to use as calibration.

[rrische]

Are you talking about barrel lens distortion?
The kind that makes all the straight lines in the photo
look curved? :cry:
I don't know of any way that's at all easy to do this.
Come to think of it, I really can't think of a way that's
HARD, either!

[Haman]

I've never had to do it before... but the only couple ideas that popped into my head are: Photoshop's spherize filter on a negative setting (it's pretty harsh, but maybe it could be manipulated successfully), and then boujou, the tracking software, has a way to correct lens distortion on an image, and export a corrected image. I'm not sure if that program can manipulate a single still image, since it typically works with sequences of images... but it may be worth a shot if you can track down a copy of the software. www.2d3.com (http://www.2d3.com) is the site for the software company, but if you're resourceful, you can track down someone at a school or company, who has a copy of it.

[anthonyBloor]

When Icarus was free that had a very good lens distortion toolset, you could draw a curved line along what you know should be a straight line, and it could estimate the focal length and correct the distortion, this is very useful for tracking and adding 3d elements, it can ofcourse reverse the effect too.

However pixelfarm on it now, and I believe they put it into its own package, there are evaluation versions available on request, in the past they have been very helpful to me.

I believe there is also a toolset or method for shake, but i cant remember its name, but it runs more a long the lines of spherise in photoshop and doesnt have the same tools as icarus for accurate results

[Nazgul]

Thanks for the info

Yes i'm talking about lens distortion..
Pftrack cost alto of $$$ and was wondering if there was a cheaper or freeware way of fixing barrel distortion.

Thanks for the Icarus info.. i think i remember that.. it's been a while since the app got bought out by Pixelfarm..

[chris_mac]

What is the best method to undistort Lens Distortion from photos. eg wide angle

I have also shot a reference checkerd board grid to use as calibration.

...Photoshop's spherize filter on a negative setting (it's pretty harsh, but maybe it could be manipulated successfully)...

I've found that if you double your canvas size before using the spherize filter in Photoshop, it tends to help a great deal in these situations.

If you have shot a checker board grid as a reference, a bit of trial and error should give you pretty satifactory results.

[Tchook]

Lens distortion can be a real problem, especially when you are working with anamorphic plates.
I have no "ready-to-use"solution but there are some tools in after effect that might help you.
try the optic compensation plug-in (its in the pro bundle i think) you can

-undeform the plate than compose un redeform (this might be ugly cause you have 2 process so be carefull with it)
-deform your matte or whatever than compose.
This might work, but it most cases it doesnt.(if your matte covers the entire frame)
So you can separate your matte in 5 or so parts with large mask and large feather and apply separate distortion its a bit "piggy" solution but it works.

There is also an another plug,the mesh warp, which is a grid of distortion
you can define the subdiv of the grid, and edit each intersection.
this can be usefull when you have the camera tests (like you did).

But if you have shoted only "stills" you have plenty other solutions.
even in ps.

hope that helps