Message text written by INTERNET:[EMAIL PROTECTED] >I guess, now my questions would be, do you know which one would give a better corner performance, 17mm/4 or 16mm/2.8 fisheye? Also, I understand that the biggest drawback of SLR ultrawides is distortion -- how bad is it in 15mm/3.5? Again, if it's predictable (read: can be removed in photoshop), it's not a problem.
Best, Mishka< FWIW, i use my Sigma 15-30 for panoramas that i stitch too. for my lens, the issue is corner softness. ordinary distortion isn't significant as the panorama program will correct for any barrel or pincussion distortion. corner softness is a bigger problem because the corners get stretched, exaggerating any softness there, and then blended with other corners. you may notice a blurring in and out effect as you scan across the panorama. the only counter to that is to soften the entire image with a small Gaussian blur. OTOH, your stitched images, if you orient the camera vertically, will have so much resolution that you have downsample for printing at reasonable sizes and the softness will not be as apparent. the ultimate test short of making a full sized print is to make a high resolution Quicktime VR and spin it slowly while zoomed in. Herb....
