Footage of different framerates in Adobe Premiere Pro Background information 

I'm going to create a audio/visual production with two camera's. One camera uses 1920 x 1080 with 25fps rate. The other camera is the GoPro camera. There are several video settings for the GoPro camera, these are: 


3840 x 2160 with 15 or 12.5fps
2704 x 1520 with 30, 25, or 24fps
1920 x 1440 with 48, 30, 25, or 24fps
1920 x 1080 with 60, 50, 48, 30, 25, or 24fps
1280 x 960  with 100, 60, or 50fps
1280 x 720  with 120, 100, 60, 50, 30 or 25fps
848 x 480  with 240fps 


After recording I'm going to merge the recorded footage from both camera's together in Adobe Premiere Pro. The settings I will use for the project are 1920x1080, 25fps. 

My question 

Which video setting would you recommend me for the GoPro? 

I could go for the 1920x1080 with 25fps rate. But than again I have the possibility to use 50fps. But than again, would the 50fps footage give the 25fps project somehow a quality loss?
It depends on the shutter speed being used on the other camera.  If the shutter speed is faster than 1/50th of a second, then shooting at 50fps and discarding every other frame would be the same as shooting at 25fps, but it means that your shutter speed must be faster than 1/50th of a second.

If light isn't an issue, then the faster frame rate won't have an impact, but if light may require a higher ISO and degrade the footage unnecessarily.  Similarly, if you aren't planning to need any slow motion shots, then there isn't really any great advantage to shooting at 50fps as you gain nothing.

Overall, say go with 1080p and 25fps on the GoPro unless you need to do slow motion and have sufficient light, in which case go 50fps on the second camera (or better yet, do 25fps for all but the slow motion shots and move to 60fps for the slow motion shots since the frame rate will be altered anyway.)