My previous email never appeared, perhaps it was because I forgot to change the subject? Anyway, here it is again.. ------------------------------------------------------------- Hi Jim, Jim Davis <[EMAIL PROTECTED]> wrote: > I checked your images - wow, that's a lot of distortion for only 28mm. > My EF 20-35 doesn't distort nearly that much at 20mm! Of course in the > real world, (not shooting rectangular objects straight on) it would rarely be > noticed. I'd be interested to know at what FL that distortion staightens > itself out. I tested the lens at 28mm, 35mm, 50mm, 100mm and 135mm. For each FL, I shot the first frame at AV 8.0 and another 2 more closeups at AV 5.6 and AV 11. The results that I got as a rough guide (I shall use my own objective terms, you really need to see the photos when I put them up later to see for yourself): Distortion at tested AV and FL: 28mm - very significant barrel distortion 35mm - slight barrel distortion 50mm - insignificant pincushion distortion 100mm - slight pincushion distortion 135mm - significant pincushion distortion In order of seriousness: insignificant slight very significant I have done another set of tests for FL 28mm at largest to smallest AV (incorporating a set for near subjects and another for further subjects) to see if there is any visible improvement on the barrel distortion but I have yet to get it processed. > I realize that we do have to live with some distortion like this on wide > angle zooms. On my 20-35 I can easily live with it for the versatility of > the lens. And I've never noticed it in the many nature shots I've made with > it, nor group photos for that matter. But if it had distortion like your > lens, I'd seriously think about getting rid of it. In fact, I've just > crossed off the 28-135 from my list of lenses I'd like to get... With so much distortion at 28mm, I still really don't think you should discount the usefulness of the 28-135. In fact, if my photos taken with the 28-135 are anything to go by, the distortions present are liveable and the sharpness & contrast provided are impressive for a prosumer lens. I am currently also trying to shoot more photos at 28mm to see if the images produced are acceptable for me. Cheers!!! Edmund * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
