Recently gotten hold of a second hand Canon EF 100-400 f4.5-5.6L IS II USM to play with and was contemplating whether to keep it and sell my Canon EF 70-300 f4-5.6L IS USM or just keep the 70-300 and move the 100-400 along.  Or the third option of keeping both 🙂

So I packed my bag with both lenses – the 100-400 attached to a Canon 5D body and the 70-300 to the EOS R.   One thing for certain is the weight difference between the 2 setup(as expected).

Using the 5D with the 100-400, initially the setup felt really heavy but after about 5 minutes I got used to it.  After taking photos with it for about 30 minutes, I swapped it over to the EOS R and the 70-300L… wow, can definitely feel the difference.

I could’ve used the EOS R with the 100-400L but I felt the balance is way off (too front heavy) although I will try using them together one of these days.

Anyway, here are some shots using the Canon 100-400L II.

And here are some using the Canon 70-300L.

One thing for sure is that even though the Canon 5D4 and the EOS R have a very similar sensor quality, the focusing ability of the 5D4 is a lot better than the EOS R (as expected).  I had good success rate tracking my son on his bike with the EOS R but it struggled with birds in flight, which is why I didn’t get to take as much with the EOS R and 70-300 combo plus the sun was setting quick and it is getting too dark for this lens.

I would like to try using the 70-300L with the 5D4 and the 100-400 with the EOS R soon….