Placing an ND filter on the lens and shooting a long exposure can give a nice moody feel. The technique is to shoot in normal daylight with ND filters and long shutter speeds.
The Sony A7R has gotten a lot of attention for light leaks that take place around the bayonet – where the chrome ring contacts the anodized orange ring.
I started with black electrical tape and recently discovered a hair tie (elastics) to be an easy, non-sticky alternative. It’s easy to carry in any camera bag too. Get the Goody variety because it does not have the metal connector and “it will give you the hold you need and the comfort you crave.” They are available at drug stores or online. They are the perfect diameter to stretch around the lens and fit snugly at the joint between the lens and body. Even if you catch them with your fingers while handling the camera they snap back into the groove. Also, it’s easy enough to leave on to cut down on moisture and dust and the possibility that “normal” exposures might be effected by a light leak. The biggest bonus is that it’s NOT unattractive!
Light Leaks with Studio Strobe (added 5/5/14)
I set up a situation that could be a real shooting scenario with the A7r and a studio strobe. The strobe was on full power 800w and the camera was held near the strobe in a manner that a photographer would stand while shooting and lighting a subject in the distance. The camera was set up as if it was a conceivable shot, not a torture test or ridiculous settings – a subject in the distance and photographer near the strobe. If my position with the camera were in such a position that when the strobe hit the bottom area of the lens on the left side there was evidence of a light leak. The exif data is 1/60second, ISO800, f2.8 (the f-stop doesn’t matter because the light leaks takes place at the mount) 35mm f/2.8 FE lens. There is an opinion that testing for light leaks on the A7(R) is not a realistic test of the camera, after all “whoever shoots at ISO25600 for 30 seconds?” Well, this test demonstrates it can happen at 1/60sec, ISO800 too. I’m not in a panic about it, after all there is the hair tie.
VIDEO of the Light Leak in the studio: https://www.youtube.com/watch?v=cbq_zXK3o0c