Fuji S5 and your Canon 18-50/17-70 lenses

Ok, so I just started working for one of those sport photography companies that say kneel, they take a picture, and on you go.

They use the S5, nice camera. Well, as I was being trained on the camera, they use 17-70 lenses. I know the lens, compliment on it and all but he asks me to take a pic blah blah long story short, the 17 on that camera was pretty sickly distorted. Like 10 is on my 10-20. You start to see fisheye.

Am I missing something? Why is 17 distorted at all? So, I did a few with my camera and 18-50 since according to him all wide angles distort *shrugs* and well, I still don't see it. As I magnify a pic or look closer, I see the possibility. Maybe my test subjects weren't great, but I got my mom to do the same pose he did and it was not nearly as distorted.

So, anyone with 17-70 and shots at 17? Heck according to him, the 16-35 should distort to. Someone help me out. Also noticed that the Fuji is 1.5 crop.

In your post, you confuse 2 types of distortion that Ultra Wide Angle lens suffer.

The first one, is more like barreling. And it's a properties of the lens. Low quality lens / Mega zooms, all suffer from barrel at the wide end and pincussion at the tele end.
Some lens are better than other. It depends on it's build.

The second distortion, is more a function of the wide field of view of 20mm and shorter focal length. It's like stretching the borders. And it's perfectly normal at theses
focal lengths.

For exemple, my Sigma 12-24 don't show much barrel or pincusion. But still show a stretched image because of it's low focal length.

Some people have problem discerning the two. Because theses problems are somewhat linked together, and are found primarily in the Wide lenses.

No confusion between the two, the 17 did stretch, but my 18 never has. I understand you 12-24 does as my 10-20 does, but you don't have anything shorter. Have you used anything like what I speak?

Problem is that while I don't have a 17-70 so I can test the same lens on a diff camera, i have a similar lens and well for there to be that much difference from 17 and 18 doesn't seem right.

You said you start to see fisheye...
Fisheye effect is a heavy barrel distortion.
And not desireable in a rectilinear lens.

Check http://www.photozone.d​e/8Reviews/index.html for distortion test on theses lens?

Or I'm missing the point completely here...

Seems right, I just don't get why I don't see it on my lens shot at 18. On that site though it clearly shows that it should. Hm. Thanks. Just weird that I never saw it but with the 17 it was clear as day.

Maybe the subject was more prone to show lens distortions?

If you use a wide angle lens and get too close to your subject you will encounter "perspective distortion", also called the "dog-nose effect". It is a well known phenomenon peculiar to that type of shot and can be used to the photographers advantage, but not in portraiture. That's why most portraits are best made at about 100mm +-. The distortion at that focal length is inperceptable. I can't imagine taking portraits at 18mm. Hope that helps...Bob <><