low PV output in anything but bright sunshine

[davidwf15]

I have a system comprising 14 x 475W new this year Aiko panels in 2 strings of 7, all facing south with no shadowing at all....I am finding that early morning and late afternoon the PV falls off dramatically
example from this morning - and apologies for the disgusting state of my windows! - I am generating a lowly 345W

literally 10 minutes later and I am generating 2.8kW....same apparent level of sun, no cloud, light level looked the same

In the afternoon it is the same in reverse.....plenty of sunlight left although it is not now shining on the panels, generating over 3kW, 10 mins later maybe 500W then nothing

I would have expected to see it dropping off more gradually over a longer period
In devices/inverter/ real time/ the PV is showing around 200V but the current draw is miniscule and therefore the output power is also almost nothing

Could it be something with the MPPT settings in the inverter ????

A neighbour has 20 year old 250W panels and generates WAAAAY more than we do on cloudy days .....just over half our prospective PV in fact ....I would have thought our super duper up to date state of the art panels would be better than his....obviously in full sun we produce way more than he does but thats not in question

[MaterialBarracuda48]

That tree looks like it will cause shading, cannot see the evening side of the street.