In a message dated 11/9/2007 11:23:06 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: In a message dated 11/9/2007 11:14:38 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: > And anyone who wants to expound more on the difference between barrel > distortion and perspective distortion, too, feel free.
============= A couple more questions, though this is late and I need to think about it more. I might phrase it better tomorrow. :-) I can see how the sensor is a flat plane, and if I am shooting upward I am creating an angle -- the light is coming in at angle to that plane. If I have that right. Especially noticeable when shooting buildings that have straight lines. So prospective distortion could occur even with a non-wide angle lens, couldn't it? Like I think the leaning lamp post I got with the 50-200 at 63mm was actually perspective distortion because it was not perpendicular, but it was not curving. I was shooting upward a bit. But I will have to go back and look it may have been curving a bit too. So the second question is, why is perspective distortion much stronger and more usual with a wide angle than a "normal" focal length of 50mm and above? I think the barrel distortion I have noticed now and then is much more minor than the perspective distortion I have noticed. But maybe I should find a brick wall and do some tests. :-) Third question is, what causes barrel distortion? The curvature of the lens surface? Surprisingly enough none of this was ever covered in any photography class I have taken. f/stops, shutter speeds, etc., etc., but not distortion. Thanks, Marnie aka Doe ;-) --------------------------------------------- Warning: I am now filtering my email, so you may be censored. ************************************** See what's new at http://www.aol.com -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
