we have different lenses i believe.

What you are both noticing is Barrel Distortion. It is quite common in wide angle lenses. WA adapters seem to exaggerate the effect because the optical design is generic and can't take the original lens design into consideration.

The effect can be reduced by designing rectilinear WA lenses. Rectilinear WA use aspherical lenses elements and floating optical groups to reduce barrel distortion. Straight lines (even at the edges of the image) appear straight in a rectilinear WA.

Yes, but how does that help US? I almost bought the canon WA lens, but decided I wanted the 16x more.

In my opinion the best corrected wide angle is the Canon 3X. Century Optical makes a special WA adapter just for that lens. While I've not used it, others I know are extremely pleased with the results and shots I've seen exhibit very little barrel distortion.

Barrel distortion is reduced by zooming in slightly. But the more you zoom in, the narrower the angle of view. So, it's all a big trade, reduced angle of view or barrel distortion. Your choice, or new lens and adapter.

Im experiencing a squashed image, its not just the corners. Is that normal?

Are you accidentally in anamorphic mode?

Nope. If it would help, I could upload a comparison.

confused and bewildered
 

I'm probably being unnecessarily thick here, but does this mean that the Canon 3x needs an adaptor to correct distortion, or that you can add an adaptor without distortion? Jim MacAllister's article suggested it was pretty much distortion-free.

Sorry, I should have been more specific. The 3X is virtually free of distortion. Some users have put a more generic WA adapter on the 3X and the distortion is fairly noticeable. However, using the Century adapter made for the 3X, the images show only slight barrel distortion.

Here is an example of what I am talking about. You can notice the first is a bit squashed horizontally. The first is with the canon 14x manual + .7x century optics, the second is the 14x alone, both at widest focal length.

http://pcp03932387pcs.sthind01.mo.co...istortion.html

I realize the picture is not focused properly and the white balance is not set, but i just had to capture something, and i didnt put a whole lot of thought into it.

Stephen

I suspect it might be the low camera angle, but I certainly see the distortion in the "normal image." Try to shoot a more controlled test. Shot the cover of a magazine or something similar. Line the camera up so the optical axis is perpendicular to the subject. Shoot it both ways and post the results.

I tried to do that originally, but I wanted to keep the focal length the same. Ill do that as well.

stephen

By doing that test, I found no distortion. intersting enough.

I suspected as much. The change is a result of the change in perspective (low camera angle vs. normal camera angle). When the camera is low and the subject (your head) is high, this effect becomes noticeable to the eye. If you place your subject near the corners you'll also get an odd perspective that the eye will find unusual.