Fix wide-angle distortion ?

[yukon33]

Hi

In my first attempt at wide-angle filming on my Canon XM2 (0.5x Red Eye Lens), I am generally pleased with the results in the large, spacious areas of my interiors - but closer shots are a different story.

The 'barrel' effect is very noticable in some shots, particularly in those with straight lines! (Such as door frames).

I use the old Liquid Edition 6 because I am familiar with it, though I am capable of upgrading to Avid Xpress Pro in the near future.

Can I fix the 'barrel' effect on my footage within either of these editing packages, hopefully Liquid Edition? Or can any other editing software or gadget do it for me?

Nearest thing I can find is the 'Magnify' effect in Liquid, which I have used to create a subtle barrel-like effect in the past. However after fiddling with the settings, i cannot seem to get it to 'invert' (or apply a 'pincushion' effect) to reduce bulging of the image and 'bring it in' from the centre. There seems to be no way to rotate the effect itself to 'flip the magnifyer over' which may have presented a solution.

Any help, or suggestions much appreciated.

Cheers

[yukon33]

I managed to get one reply to this advising to try the Pinch/Punch effect in Sony Vegas, which I have experimented with but unfortunately it does not seem possible to configure the settings to reverse the barrelling distortion.

While the footage is frozen on one frame and the picture is 'squeezed in' to the centre, yes it looks almost fixed... but once the footage is played and the camera is moving, it is clear that this post production application cannot simply flatten the image by reversing the magnification effect created by the wide angle lens.

You would think that considering the wide angle lens is round, with its magnification properties symmetrical and peaking in the centre, that one could apply a reverse magnification in exactly the same place of the footage as a counter balance.

I also cannot believe after searching the internet that this problem is not more of a concern - 'don't buy cheap lenses' seeming to be the most popular comment here, but while we all should know we get what we pay for, there must be an application or plug in for some editor somewhere than is programmed with the maths to fix this ugly, and very common, 'barrelling'?

[lordsmurf]

Don't buy cheap lenses is the accurate response. Or use a different angle.

I deal with this in so-called "still" photography. I've got some high-end lenses by Nikon and Tokina, but the nature of the angle is distorted to some degree, and it varies from edge to edge.

dXo Optics has special software that I use to reverse this. I'm still waiting on D3 support, having to shoot fisheye and wide with D200 at the moment (if it requires de-distortion).

[guns1inger]

I have seen still image filters for this, but not much for video. Mostly, wide angle lenses that fish-eye are used knowing that it will have an effect, and are used accepting this fact.

I have read a couple of snippets that suggest ZS4's distortion effects might be able to do it. Don't know if they are any better than the pinch/punch effects in Vegas. I guess you lose nothing by trying it out.