Sony Movie Studio 12 edits fine natively GH3 50P 50Mbs mov files. You can then render to 50/60P with high bitrate and quality remains. You can use Main Concept AVC (mp4 h.264) and enter manually 50/60 fps to check box because it is not in dropdown menu. GPU rendering with AMD card is in my system 2-3 times faster than with CPU. If you want to make several rerenders in project then I recommend at least 70-80Mbs because it is destructive h.264. There are no professional codecs in this cheap version other than uncompressed avi.
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