- Joined
- May 14, 2016
- Messages
- 159
- Reaction score
- 53
I shot some 1080p 60 fps video on my Phantom 4 (P4) and was very disappointed by the quality. It looked blurry as if over compressed. I’m wondering if others have run into this, if it’s a well known problem, or...
Here’s my thinking about it all: I understand that P4 max video throughput is 60 Mbps. (Page 60 of the manual, last line says “Max. Bitrate Of Video Storage 60 Mbps“.) Using the Movie Inspector in QuickTime I see that the data rate of 1080p at 30 fps I shot on my P4 is about 40 Mbps. Assuming that’s true then the data rate at 60 fps would require twice that of 30 fps, or about 80 Mbps throughput in order to achieve the same level of quality. Have I got that right?
When I shoot at 1080p, 60 fps and inspect the throughput using the Inspector in QuickTime I see that the data rate is 60 Mbps. In other words, 20 Mbps is being lost because you can’t fit 80 Mbps through a 60 Mbps pipe. This could well explain the over compressed look of 1080p 60 fps P4 video: the P4 is taking the 80 Mbps stream and compressing it to fit into the 60 Mbps pipe. I haven’t shot any 120 fps 1080p. After seeing how poor the 60 fps 1080p looks I don’t see the point. At 720p, 60 fps the video looks fine. The data throughput at that resolution is only about 20 Mbps.
Can others confirm or refute my thinking please? I want to be sure I’ve got this right.
Thanks.
Here’s my thinking about it all: I understand that P4 max video throughput is 60 Mbps. (Page 60 of the manual, last line says “Max. Bitrate Of Video Storage 60 Mbps“.) Using the Movie Inspector in QuickTime I see that the data rate of 1080p at 30 fps I shot on my P4 is about 40 Mbps. Assuming that’s true then the data rate at 60 fps would require twice that of 30 fps, or about 80 Mbps throughput in order to achieve the same level of quality. Have I got that right?
When I shoot at 1080p, 60 fps and inspect the throughput using the Inspector in QuickTime I see that the data rate is 60 Mbps. In other words, 20 Mbps is being lost because you can’t fit 80 Mbps through a 60 Mbps pipe. This could well explain the over compressed look of 1080p 60 fps P4 video: the P4 is taking the 80 Mbps stream and compressing it to fit into the 60 Mbps pipe. I haven’t shot any 120 fps 1080p. After seeing how poor the 60 fps 1080p looks I don’t see the point. At 720p, 60 fps the video looks fine. The data throughput at that resolution is only about 20 Mbps.
Can others confirm or refute my thinking please? I want to be sure I’ve got this right.
Thanks.