BySteve Lowry 2018-10-31 8028
Bitrate is a very important parameter when you shoot video. When the UAV or camera is shooting video, the file of video is too large and must be lossy compressed. Therefore, the lower the code rate of video, the more serious video compression, the image quality may be damaged. So if you want to have good picture quality, you need a higher bitrate.
Take DJI INSPIRE 2 for professional film and television as an example, it needs to shoot high quality video, so the video code rate is huge. For example, when shooting 6K RAW non-destructive video, the code rate can reach up to 4.44 Gbps; Even to shoot the slightly inferior 4k ProRes 422 HQ lossy video, the code rate is about the same as 1Gbps.
So, there is only a cheap SD card of 20-80 Mbps in the market, which can't get a high quality video of INSPIRE 2.
Therefore, many INSPIRE 2 players must buy a specially designed CINESSD (above) in DJI, which has a super-fast SSD that is dozens of times faster than a normal SD card and 4 Gbps above, so as to liberate the powerful filming performance of INSPIRE 2 .
Although neither of us is a professional photographer and we don't need to shoot 4k RAW video, we can't use a monster like SSD, which is expensive and big. However, in recent years, the camera has become more and more powerful, and the bandwidth required to shoot video is getting larger and larger. As a result, the memory card in the past has become inadequate.
For example, at that time, many people used 16GB Lexar 633x SDHC card on Mavic Pro. Since the Mavic Pro code rate was only 60Mbps, while the Lexar 633x rate was 80-95mbps, which was enough. But what if this 80-95mbps SDHC card was inserted into a 100Mbps bitrate Mavic Air? DJI GO pops up with a warning indicating that the current storage card may affect the quality of the shot.
Because, when the camera or memory card bandwidth is insufficient, the camera can only force the low bit rate to shoot, has the opportunity to cause painting quality deterioration.
Use SD card to "shoot", is to "write" data SD card, so "write speed" is the key! Even if you read faster, the speed of writing video to SD card will affect the quality of the picture.
The first choice is the latest Video Speed Class standard: V90 / V60 / V30 / V10 ,the second selection UHS standard: U3 / U1 ,the third selection: Class 10
However, the new standard high-speed SD card is not cheap at all. Want to put money to the knife? Start by looking at the size of your camera and the video quality you need (above).
If you need a professional video production, shoot high-quality video with something like the Canon 5D4 or Inspire 2, because the camera's bitrate image quality information is huge, you must buy an extremely fast SD card of V60.
If you're an amateur, use a professional camera like the SONY A7, or a new drone like the Phantom 4 Pro or the Mavic Air that supports a 100Mbps code rate, get an SD card at least in the V30 or U3 class. If you just want to record the scenery, use a regular 4K camera and buy a V10, U1, or Class 10 device. If you don't want quality, right? Buy at least a Class 10 SD card.
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