Canon EF 135mm f/2L USM Lens ( Camera Shake )

Bought a new Canon EF 135mm f/2L USM Lens and testing for the past week on my Canon 6D. I am coming to find out this semi telephoto lens needs to be mounted on a monopod or tripod (in my case) if I want to eliminate all camera shake. I have been testing outdoors and naturally hitting very high shutter speeds which I did not expect to see camera shake in those photos.

Keep in mind I am pixel peeping, viewing photos full size might would only look slightly soft where it should be sharp. Pixel peeping, most all of the photos where indicating camera shake, now their where a few shots that where surprisingly free of camera shake. For example, a shot with a shutter speed of 1/160 came in crisp and clear, can only conclude it was just luck on my part. On the other hand, many photos with shutter speeds of 1/400 and greater showing some camera shake as there was nothing crisp in the shot, which should have been.

I have a Sigma 50mm f/1.4 Art lens which I have no problems with camera shake in my photos. By the way, the Sigma 50mm ART is an awesome lens and it is making me question the quality of the Canon 135mm copy. It was very difficult for me justifying the cost for the Canon 135mm and the shake has taken away the excitement I had for the lens. The main reason I bought the Canon 135mm lens was for doing portrait gigs. Now I will be forced to shoot with a monopod now, which will only slow me down on location portrait shoots. However, the shots will be without camera shake.

Defective Lens, or just me?

Is it fine with the monopod? Are you sure it's camera shake and not focusing incorrectly? You really should not have camera shake at 1/400, but that is also not the lens's fault. If it is truly camera shake it will go away either the tripod or at a high enough shutter speed.