Re: Lag between FPV and actual position in the sky of the P2
Following on from Cityzens suggestion about a rapid sideways movement being detectable for lag, I remembered that with the asymmetric position of the camera in the P2V+, a sudden sideways movement of the phantom to the left causes my left side landing gear to come into view on the fpv screen. I tested this a few minutes ago by eyeballing the fpv screen camera, the phantom and the control as I caused the phantom to lurch to the left in my garden (the wind had dropped from 50 kts overnight to 5kts now thankfully).
Visually, the movement of the phantom in the sky and the appearance of the landing gear on the fpv screen appeared instantaneous to the eye so this unscientific test does indicate that when using a modern smartphone ( I'm using a Samsung Galaxy S5 by the way -great screen and very responsive ) the lag is virtually non existent, so I'm quite happy with that.
I reckon this could be repeated with someone videoing the vision fpv screen close up with the phantom also in shot. By viewing the resulting video frame by frame if necessary then a more accurate measurement could be made since we know the frames per second rate and 25 fps is 40 millisecs between frames.
Nice to have a forum like this where we can bounce ideas around (but hopefully not phantoms) and discuss things like this.
Messiry indicated how difficult he found it to see the fpv screen in sunlight and how difficult he found it to judge the orientation of the phantom when it is any distance away. I think that most people find watching the phantom and the screen at the same time quite difficult, particularly when the phantom is some distance away, so he is not alone there. It is not unusual for me to glance down at the screen to check some parameter and then look up again and not be able to see the phantom in the sky. It certainly can put you in panic mode. I'm now not afraid to put faith in the radar and to simply rotate the phantom out there somewhere until the radar shows the radar arrow pointing towards me and simply fly it back towards me, watching the screen and the distance, height parameters at the bottom. I progressed to NAZA M modes so there is also that very useful get you back mode of Home Lock too. Always worth validating that your home point really is home by checking out how the parameters are panning out when you are flying close to take off point.
Also worth remembering that not all screens are equal, I've a 7" Samsung Tab 3 that I thought might be better than the Galaxy S5 with its 5.1" screen. In reality the 7" tablet is awful to view outside compared with the Galaxy. I've also bought a cheap sun cover for the S5 but TBH I very rarely use it, I just up the screen brightness to max and it is reasonable in most conditions