The0dora Photography (now dorcam1653)
Lens experiment
Given that this is not a controlled experiment and by no means is it conclusive or in any way a degradation of either lens and that this is purely a personal visual interpretation conducted with my specific camera the 5D MarkIII using 2 different lenses - 17-4L series Canon F4 and the 12-24 Sigma 4.5 to 5.6 here are the results. I picked 1 image from both lenses as closest to time value. The ISO was the same. The tripod is in the same position. The focal lengths are different. I have taken both images into Camera Raw hit the auto button and straightened them - no lens adjustment.
The images were taken 2 minutes apart. Consideration needs to be given to external factors such as different focal lengths and or movement, etc. My personal preference is for the Sigma 12-24. See what you think.
Lens experiment
Given that this is not a controlled experiment and by no means is it conclusive or in any way a degradation of either lens and that this is purely a personal visual interpretation conducted with my specific camera the 5D MarkIII using 2 different lenses - 17-4L series Canon F4 and the 12-24 Sigma 4.5 to 5.6 here are the results. I picked 1 image from both lenses as closest to time value. The ISO was the same. The tripod is in the same position. The focal lengths are different. I have taken both images into Camera Raw hit the auto button and straightened them - no lens adjustment.
The images were taken 2 minutes apart. Consideration needs to be given to external factors such as different focal lengths and or movement, etc. My personal preference is for the Sigma 12-24. See what you think.