So this is a pointed question, but could certainly turn into a broader topic of lens testing.
So yesterday my brand new 70-200mm f/2.8L IS II USM arrived, and I couldn't have been more excited. I've been scoping it out for awhile, and finally pulled the proverbial trigger when I'd squirreled away enough money. I'd long heard about how amazingly sharp this lens is, and already owning two other L lenses, I definitely have the red ring addiction.
So I got home and decided to test the lens, since I've had some some copy issues with Sigma (I know, they don't have Canon's QA). I compared it to my primary lens, the 24-70mm f/2.8L. I took pictures of one of my wife's cookbooks at 70mm (obviously the only comparable focal length) at apertures f/2.8, f/8, f/11, and f/16. Camera (5Dm3) was tripod mounted, ISO set at 100, mirror locked, and shutter triggered by a two second delay.
I gotta say, I was a little surprised when the two lenses came out pretty close in terms of sharpness at 70mm at f/2.8. While the 70-200mm was a hair sharper, it wasn't the "omg the 70-200mm blows the 24-70mm out of the water" that I had expected. I wish I had comparison images to post, but unfortunately I left my camera at home, and wanted to post this topic while it was fresh in my head. I'll post the photos when I get home tonight.
So I have two questions:
1) I'm no professional, so does anyone who is or has experience with these lenses have any input? I'd heard the 24-70 was notoriously soft (never really noticed it myself), and expected the 70-200mm to be noticeably sharper. Bottom line, I'm concerned I may have gotten a soft copy of the 70-200mm, and at $2500, I'd likely get it replaced if that's the case.
2) Does anyone have a favorite method of testing lenses? I've often photographed a newspaper taped to a wall or something similar (cookbook) to check the center, corners, etc at various focal lengths and apertures. I'd love to get one of those testing charts, but they're wildly expensive online and I'd rather buy actual gear.
Thanks in advance for any advice!
* Posted this in rumors by mistake. Moving to Gear Talk.