SJCam SJ7 Star - true 4K! compared with Yi4k and Foxeer Legend 3

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►lots of sample pics

My thoughts / findings:
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+ Dimensions match Gopro3/4
+ high buildquality (alu frame)
+- touchscreen nice, but handling not as responsive as smartphone (or Yi4k)
+ touchscreen AND buttons
- charge LED not very visible
- charge with USB MINI (like Gopro3/4) USB micro would be more common?
- scaling down of fast FPS looks terrible
- medium and narrow FOV on 4k makes no sense! should be left out since it produces ugly quality...

Yi4k: lesser distortion, looks "nicer" to the eye - but in 100% crops the image looks less detailed than on the other two cams!
Legend3 has more wideangle than SJ7star, else similar sharpness and details, but "vignetting" on the edges. FL3 has NO! purple fringing!
If you dont have to zoom in (for example film in 4k and then take a 1080p crop) the Yi4k still looks better.
Zooming around in a 4k timelaps on the SJ7star is really nice - lots of details and reserves to zoom...

Batterytime comparison (all 4k 25fps):
Yi4k: 93min
SJ7:  65min
FL3:  53min