To Thundering1: altough today I am professional illustrator and only an amateur photographer, I have been technical editor in a photography paper during very long time (until 2002 so AFTER the replacement of silver photgraphy by digital one), I then wrote more than 350 articles and 8 special issues, 3 of them devoted to lens tests by the MTF method, 2 about tests of electronic flashes and 3 about tests of various photographic devices. I have been in charge from1977 to 1985 of the test of some 500 lenses on MTF bench. Therefore I know very well the situation which you explained by your draft.
Altough I have been Photoshop teacher for nearly 4 years with 99 sessions done, I was interested by your approach of correction of the elongation of surfaces, so I am grateful for your comment.
To PeeWee05: I share your point of view. This was why I did not corrected the picture. Formerly I had a Pentax 3.5/15, which I made modify to fit my Minolta XM SLR (a strange top level SLR with interchangeable viewfinder), because the lens was originnally in K bayonet mount. Richardphotos also likes this photographic approach (he has the same Sigma 4-5.6/10-20 Pro EX lens), and this is the reason why I dedicated him my pict.
Today as an illustrator I like wideangle perspectives too, and you can have some examples of drawings using photos made with my Pentax 3.5/15 lens on Minolta XM:

"Kim 3: 125° without distortion":
http://www.renderosity.com/mod/gallery/index.php?image_id=1344980

"Iris 6: of steel and glas":
http://www.renderosity.com/mod/gallery/index.php?image_id=1346482

"Schoelcher panorama":
http://www.renderosity.com/mod/gallery/index.php?image_id=1365071

"Szanden bathing" uses several Artmatic Voyager renders carefully assembled to create a vertical panorama (contains nudity):
http://www.renderosity.com/mod/gallery/index.php?image_id=1480267

and this twin-page comic draft starting of a render done in Cinema 4D R9.0 with a ca. 120° perspective (contains violence!):
http://silviarobin.elcet.net/pages/page_6.html

Have a good end of week

Edouard