5d MKIII Silent shutter mode

The halo is simply the HDR processing style that you have used. Choose a different style.

I am not very impressed with the in-camera HDR processing. In hand-held testing, I found it was quite poor at aligning images even with very limited movement (trying shooting architecture with hard straight lines). Processing with an off-camera package gives much better results (and you can use an image processing style that doesn't render the images like some kind of tacky cell-phone/Facebook picture...).

The silent shutter mode is, however, excellent.

Aside from a little more lag and the reduced burst rate, I can not see any downside. As well as being quieter there is also much less vibration, which should help give you sharper images.
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