need help with video file size

[Marko5584]

Greetings,

I have a Phantom 3 and I have been using it for a few weeks. I recently noticed an irregularity in recording video and would like some help with fixing it. I record video at 1920 by 1080 at 30 fps. Typically, a ten minute sequence takes up around a gigabyte of data on the sd card, but sometimes the same length in video (in the same 1920 by 1080 frame rate and same 30 fps) produces a much bigger file (nearly twice the size) resulting in a 2 gigabyte video file.
I have compared the video files and notice the larger file has a much higher data rate or bit rate than the the other files. Typical data rates are around 11772 kbps, but the big files have a much higher data rate of 24996 kbps. So what is the extra data due to? Where is it coming from? There's no difference in the video resolution. In each case the frame rate and frames per second are the same: 1920 x 1080 at 30 fps. But the data or bit rate is much higher on some of the anomalous video files.

Any ideas here about how to bring this data rate back down?

Thanks.

Marko

 

[Meta4]

Typically, a ten minute sequence takes up around a gigabyte of data on the sd card, but sometimes the same length in video (in the same 1920 by 1080 frame rate and same 30 fps) produces a much bigger file (nearly twice the size) resulting in a 2 gigabyte video file.

Any ideas here about how to bring this data rate back down?

It's probably in compression.
If you have a complex scene it won't compress as much as something with a lot of the same colour like large areas of sky.

 

[Marko5584]

Thanks. I will compare some video sequences. This one was at dusk over treetops and a field. It was not good lighting.

I never had this issue with the phantom 2 vision+ that I previously owned.

http://www.planetcanadice.com/Movies/LightandWater.mp4