Roger Francois Lotte worked for his father Francois Lotte until around 1960. Prices for good Lotte bows have risen rapidly over the last few years – the bows aren’t getting any younger, and there’s greater demand from players for good French bows … what Peter Horner of Bromptons describes as “a toxic equation”.
Both Francois Lotte and Roger Francois Lotte seem to have used rather lumpy pernambuco on occasion, and you often see quite warped examples in auction houses (though these can generally be re-straightened very effectively). Francois Lotte liked to make his bows rather long, often nearly 75cm.
Roger Francois seems to me to be a far better maker than his father, and his bows often have the playing qualities you’d associate with much more valued makers. However, both father and son produced immense numbers of bows, and the quality varies considerably.