I have taken a look at your shots and found that your nodal point setting is out by a country mile. You will need to adjust this.
I can tell you that the nodal point on a Sigma lens is about in line with the "Gold" band near the front of the lens.
Information on finding your cameras nodal point can be found here
Also to get the most out of your camera (and a very nice one you have) use the maximum resolution or at least something is the higher scale. That images you posted where tiny. (Although this may have been only for this test)
Good luck and lets see your next shots with the nodal point sorted out.
You are right Robert,
No such luck with the 300D or 10D as they do not have a full frame sensor like the Canon 11.1 megapixel 1Ds.
They use a multiplication factor of 1.6
I only wish it was that easy to stitch with my 10D or better still I wish I could afford to buy a 1Ds.
u got any images taken by ur 10d and fisheye for our perusal??
Also... what r u useing to stich ur shots with? Oh yeah... and if Easypano offered a four image stich... ie 4x 90 deg. would that make the stich possible?
If I only had an hour to chop down a tree... I'd spend 45 mins sharpening the axe.