I'm always a skeptic and sometimes get sucked into the "better images by science"-ness of this forum and doubted the 50L. But the recent postings of reviewers clamming a possible change in production and improved performance peaked my interest. It is expensive when compared to the Sigma (no real world exp with) and totally justifiable when compare to the Canon 1.4 IMO.
I was disappointed at the initial sharpness of the lens when I was doing the ruler shots to calibrate the micro adjustments (only a +4 adj needed). Now with some (not a lot of) real world shots under my belt, I feel some shame for doubting. Real world situations have me felling very different.
I experienced NO focus issues, front, back, left, right, didn't happen.The focus is reasonably fast and accurate.I did however experience the most ridiculous bokeh and shallow DOF I have ever seen. Due to it's much closer MFD some of the shots were beyond what the 85L could do.
The build quality is that good. I feel safer with this lens than any other since there no protruding or sacredly vulnerable front or rear elements like on the 85L. Even the 85L's AF and MF ring reminds you that it may be a little fragile whether it really is or not. The 50L is stiff and deliberate.
The colors are amazing. Even at 1.2 the colors are very, very vivid and contrasty. It is at least as good as any lens I've shot with if not the best. I am really impressed with the color, love is a good word. (None or the images posted have been corrected other than wht balance).
It seems CA is much better controlled compared to the 35L and the 85L. I have not done head to heads on CA but judged by previous experience reference only.
My summation is; If I had to shoot laser printed text all day long the 50L would not be my lens of choice. It is no macro lens by any means but sharpness is good (even really, really good at times).
While the Sigma may be as good for a lot less, I may never know. I am so impressed at this point I will definitely be keeping this lens. I don't know if I've gotten very lucky or I'm just not that picky (pretty sure that isn't the case) but this lens works for me.
With all this said, I have become quite experienced with shallow DOF of wide, wide apertures as of late. All of the following shots are hand held. Some with lower than the 1/FL rule of thumb shutter speeds.
No Sharpening was applied to any images.
1/1000 @1.2
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800px 100% crop
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1/60 @1.2
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800px 100% crop
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1/50 @1.2 (This shot made me fall in love with this lens).
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800px 100% crop
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1/30 @4.0
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800px 100% crop
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