Same here. Though R5 is not in reach for me yet, I am very interested in its capabilities.... and I'm really curious what it will do if the distant object has more contrast in the eye?
I prefer not using the TC for BIF as I like the wider field of view for tracking. For that reason, I don't use crop mode but crop in post.Used the 100-500 this weekend without the 1.4x just to see what I can do with the extra stop of light. Lots of activity at the osprey nests Saturday, at least 1/2 dozen pairs are building/repairing. Not that the 1.4x is any slouch, but I notice a positive difference without it. Crop mode on the R5 picks up the slack easily. Not much time to process images, managed just one to post for now.
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