A Remarkable Long Lens

ProDude wrote:

William Woodruff wrote:

Lighter would be nice, and an extra 100mm would be nice, but that EF 100-400 mk2 is a spectacular lens, and it is built like a tank. I am confident that if anyone ever tries to take it away from me, I will be able to beat them to death with it, and continue shooting.

I get it. But one has to realize that technology does move on. The RF mount has compatibility with RF lenses that bring some new issues to light. Speed and edge sharpness are the 2 most prominent. Areas in particular you can expect the RF to exceed the EF's performance. I get why folks wish to hang onto their EF glass. But in almost all cases the RF glass has moved on. The 100-500 would be just one perfect example.

No argument there.  If I didn't already have the 100-400L, I would probably be in the market for a 100-500.

That said, the 100-400 does have a couple of things going for it.  The EF 100-400 has much less vignetting (although the RF lens isn't terrible), but more important (to me) is the fact that the EF 100-400 is internally focusing.  That means you don't have to move air in and out when you zoom and/or focus.  As a result, the lens is bulkier, but it is also far less likely to get dust or moisture inside.  I like that.

Functionally, the 100-400L has been flawless on the R, and on the R5.  Safe to say that either lens is a fine choice.  For now, I do not see a compelling reason to trade up.