Cheers guys!
I learnt so many things...things which I have not really thought about!
I am about to start navigating in the evening mainly between Kew Bridge-Tower Bridge, it is not too dark, but it is a good place to start.
Also, between Kew Bridge and Richmond Lock the river gets very dark, and that's where I am hoping to test/use my plotter/ sounder in the evening.
I have never been on the water in the evening but I must start before the summer as not boating in the dark has restricted our journeys a lot...
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