I just came back to this thread as the OP and see there has been some very useful and informative comments.
My initial post was whether I was in 'legal viz' as it was my flight in Haze and 'into sun' and I had no experience of 'eye balling' how far 5km to 8km looks like mid air.
I certainly wouldn't want to fly in the conditions in that video! Not until I have an IR at least or IMC.
I felt safe and used all the information available to me including weather reports, metars, tafs etc and decided to do the flight and did indeed mitigate any risks by asking for a traffic service.
Im now experienced in this weather phenomena and flying 'into sun' which ha given me more confidence should I experience it next time.
I post on here to seek opinions, advise and fact find without pride and appreciate the responses.
Thanks All!