The corner performance at 24mm is much better than the Canon 24-70L. The 24-105L produces sharp corners starting around F8 and is best at F11. Another common complaint about the 24-105L is its barrel distortion at the wide angle focal lengths. When testing the lens around the house the distortion is noticeable, but in real-world pictures distortion has not been an issue. Plus, with Canon’s free DPP software (version 3.2 and higher) the distortion is FULLY correctable. Other common 24-105L complaints are the light fall in the corners at F4-F5.6 and color fringing (CA). Again, with DPP’s software corrections these optical traits are resolved. The added lens correction features starting in DPP 3.2 are very effective.

FINDING BOKEH AT F4

So far I have written about the Canon 24-105L’s ergonomic strengths, and there is more. The 24-105L’s performance at 35mm is a hidden secret - it is actually (drum roll) - GOOD! At F5.6, F8 and F11 the 24-105L corners are SHARPER than the Canon 35mm L F1.4 and the resolving power is surprisingly similar. The 35L has a slight edge in the center of the frame, but it really is a slight advantage. If shooting landscapes, frankly, I would rather use 24-105L over the 35L. Of course, the 35L offers F1.4 which has its upsides.

F4 is as fast as the lens gets. I like shooting at faster apertures to help separate subjects from the background. With the 24-105L this is not always possible, so creatively the 24-105L frustrates me at times. To get a nicely blurred background (ie - bokeh), the key is to shorten the distance between the lens and the subject. Bokeh is possible, but it takes extra effort and a keen eye. That means looking for compositions with a close subject and a relatively distant background. Combining these two elements with F4 or F5.6 usually results in a nice bokeh. It will not be dramatic like a Canon 135L, but certainly workable.

CONCLUSION

Most photographers yearn for an ultra sharp German-made prime with a crazy fast aperture. The Canon 24-105L is the polar opposite - slow aperture, a zoom (eek!) and not the smallest, stealthiest lens. While the 24-105L may not win a beauty contest, if it were a car - it would win the Baja 500. With its rugged build, image stabilization and useful zoom range - the 24-105L gets the job done and brings home keepers.

Last summer we went to Hawaii (pictures here) and once again two camera bags were stuffed with exotic lenses and some Canon zooms. Despite the best intentions, the 24-105L IS was the most used lens. Weather was hotter and more humid than expected. Carrying around 15 pounds of camera gear in 90 degree temperatures and +90% humidity was miserable. By the second day the bags stayed in the car and the walk around kit consisted of the Canon 1Ds Mark II and 24-105L.

The best thing about the 24-105L is the confidence it inspires - I never worry about missing a picture. With image stabilization, quick auto-focus and auto aperture - I know I will get a picture. Maybe not a keeper, but I will come home with many possible candidates. Whereas a bag full of primes can be questionable. Maybe the wrong lens is mounted when that perfect picture falls into place. Maybe the wind is blowing 20 MPH with ocean spray in the air and the sand is kicking up - so lens changes are a dicey proposition. And sometimes carrying 2 or 3 lenses is just a hassle. Its the 24-105L’s utility that makes is a great lens. The 24-105mm range on a full-frame dSLR covers alot of territory. The image stabilization will help anybody’s keeper rate. The weather sealing is a nice insurance policy for when the weather takes a turn. And with Canon’s DPP software, the lens corrections address the optical shortcomings. As a total package, the 24-105L is very hard to beat.