Hi Alan, yes I'm sure that the RF2x on the RF100-500mm would provide even sharper shots and a bit more macro, but the primary reason why I bought the RF100-400mm in the first place (aside from your recommendation) was to keep the size and weight minimal. Travelling in West Papua involved a lot of domestic flights on small aircraft with limited luggage allowances. Even more importantly, it's pretty tiring for a 72 year old to hike for hours at a time through sweltering humid rainforest even with an RF100-400mm attached, and carrying my relatively heavy RF100-500mm would have been quite challenging. This is a
Hypochrysops species, photographed at Fak Fak, 400mm, 1/180, F11, ISO 1000.
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