
This is not an attack on you personally as a photographer, but this is something for everyone who reads this and cannot see what's wrong with these and be able to immediately know how to correct it.
Your EXIF says you were shooting in manual, only ISO 500, with the aperture stopped down all the time. If you were shooting at ISO 1600 and f/1.8 when using the 50mm, all of the images would be sharp, and well exposed, the background would also be more out of focus,
win-win-win!
The thing that gets me is that everything wrong with these pictures could have been easily avoidable, nobody's ready, or smiling, a quick joke could have made everyone smile, and counting down on
all of them would make sure everyone was ready. Also knowing your camera and what the appropriate settings should have been would have made these printable.
Was at: 50mm, ISO500, 1/8th, f/4. (not hand-holdable)
Should have been at~: 50mm, ISO 1600, 1/90th, f/1.8. (hand-holdable, would have been printable, and still properly exposed)
Shot at: 50mm, ISO500, 1/30th, f/2.2.
Should have been at~: 50mm, ISO 1600, 1/180th, f/1.8. (proper exposure, would have been very sharp, easily printable)
Shot at: 120mm, ISO500, 1/6th, f/5.6
Should have been at~: 120mm, ISO1600, 1/15th, f/5.6 [i'm guessing you were using the 18-135 because of the vignetting] try leaning up against something or bring along a tripod/monopod or strobes)
Shot at: 66mm, ISO500, 1/4th, f/5.3
Could have been~: 50mm, ISO 1600, 1/45th, f/1.8 (still not really hand-holdable, but would have been MUCH better if a tripod was used)
Shot at: 50mm, ISO500, 1/30th, f/2.2. (obviously not hand-holdable)
Should have been at~: 50mm, ISO 1600, 1/180th, f/1.8. (proper exposure, would have been very sharp, easily printable)
These look real shaky resized, on the web on monitors with pixels the size of legos, they're going to look worse printed.
If you're going to shoot in manual, at least take advantage of it, if the EXIF data didn't say manual mode, I would have guessed it was with the canned program modes judging from the odd exposure numbers.