Sadly there are many people like yourself who cannot see in 3D, I say sadly first of all because 3D or stereo-photography has been my hobby for over 40 years (see avatar picture), secondly I know it makes distance judgement a bit more difficult for you.

The polarising filters in the glasses don't distort or affect the quality of the image, the original films are taken with a camera with two lenses and two separate images are recorded , when the films are projected the projector has a polarising filter in front of each lens but each filter polarises the light in opposite planes, the glasses you wear have similarly opposite polarising planes, so in essence your left eye sees the film taken with the left camera lens and your right eye the right camera lens.

Therefore if you watch with one eye, you will see a perfect picture taken with the corresponding camera lens, it won't be dimmed, but it would be blurred if you kept both eyes open because on the screen the two images are superimposed one one top of the other.

I would suggest if you do go and watch it, you just cover up either lens with a piece of tape or black paper for instance, otherwise it will be tiring keeping one eye closed all that time.

No offence to the next answer, but I can say that definitively.

set the LG at about 1/3 to 1/2 volume and adjust the volume with the source control.

no, i agree with the others – you should stay away from the 10-20 as a serious portrait lens….and if you're going full frame in june you'll just have to get rid of it anyway.

a 50mm is always a good lens to have, and i'd also consider looking at the tamron 28-75 f/2.8. i'm in the process of getting a nikon-mount one for my d90, and it comes highly recommended. it covers the portrait range – 42-110mm on a crop camera- quite nicely….and you'll still be able to use it on your 5d mkII. oh, and it's only about $300.