Roger and Aaron are back at it again for Lensrentals, this time with a teardown of a Canon RF 100–500mm F4.7–7.1 lens with a little secret inside.

As Roger tells it, Lensrentals has come across ‘several’ copies of Canon’s RF 100–500mm F4.7–7.1 lens with a cracked element inside. He believes this crack occurs during shipping, but notes that ‘if you’ve ever rented from [Lensrentals], you know how we pack […] Nothing should break in shipping.’
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Continue here:
https://www.dpreview.com/news/4468228569/lensrentals-tears-down-canon-rf-100-500mm-f4-7-7-1-lens-solve-the-mystery-cracked-element