Finally! Lensrentals ripped apart a 600mm F11

This was one of my most anticipated Lensrentals teardowns of the summer, as I was curious about how Canon made these little super telephotos.  While the 600mm felt to me as a bit poorer in terms of optical quality but amazing in terms of price, the 800mm F11 is a VERY intriguing lens because it's no slower than a 100-500mm F4.5-7.1L with an extender, and not worse optical quality than the combination either - and all this for around 1/3 the price.

Chelsea and Tony also give a good perspective on these two lenses as well, so while you're reading, take a look at their video review below. (a note on the $1600 price on that video, that's for BOTH lenses, not just one)

When Roger and Aaron get a new thing into LensRentals the first thing they must do is, well, yes, tear it apart.  Lensrentals does much of its own servicing and alignment of lenses, so they have built up a vast third party perspective and knowledge on these things.

We won't get into the details much here, outside of the fact that it seems to be an oddly complex little thing to take apart and service and ultimately Roger decided that;

We’d found the electronic construction was complex for a Canon lens, or at least very different. The optical construction in the core has a very Canon look, with numerous optical adjustments/compensations using their new, large eccentric collars. I remain convinced this is because Canon is making automated optical adjustment of subgroups during assembly. Nobody else is adjusting to this degree or in this manner.

...

So we got an AFLE on this one; Another Frigging Learning Experience. And what did we learn? That we don’t want to work on the Canon RF 600mm f/11 IS STM. Life’s too short. When these break, they’re going to the Canon service center. Except for this one, cause those Canon techs would enjoy fixing what we broke far too much; we’re never going to tell them this happened.

Read the full writeup here including such lines as "you can come off, or you can melt; your choice." which cost me to lose my morning coffee.