Puzzled

At the moment, I remain puzzled: at 10mW I was surprised that FT8 worked at all on 6m. Already today (presumably by Es) 10 stations have spotted me on 6m FT8 at 10mW.  

At 13dB weaker my 10m WSPR at 500uW remains unspotted. I had assumed that signals 13dB weaker might have been harder, but then WSPR works with signals considerably weaker than FT8.

Probably Jan OZ9QV is correct, that the far shorter TX period for FT8 (about 15 seconds) catches very brief Es bursts with FT8 that the 120 seconds needed for WSPR does not decode: the Es cloud has to remain around for longer.  Perhaps Es just bubbles up for very short periods more than we thought. Maybe FT4 would be better still, even though it is even less sensitive?

With FT8 I am pleasantly surprised how well just 10mW works with 6m FT8.  Of course the WSPR signal at 500uW is more likely to be buried in noise too. Overall, I suspect the briefness of FT8 must help more than I was expecting.