Taken with Canon 100-400mm at 400mm wide open f/5.6, Thousand Oaks Type 2+ Glass, IS turned off, tracked by Meade LXD55.
Taken with Canon 100-400mm at 800mm wide open f/11 (Kenko 2x), Thousand Oaks Type 2+ Glass, IS turned off, tracked by Meade LXD55.
Both autofocused by LiveView contrast detection, I would say the result is very excellent, sharp and well defined edge. Now I will need some sunspots around to conduct any futher test, and maybe I shall use this combination for the upcoming partial eclipse and any total solar eclipse trip that I might go in the future.
This solar filter is originally bought for my Tele Vue Ranger and it's a perfect fit with this lens, even better than the Tele Vue Ranger!
A very tight fit, just perfect! Judging from the result, I guess that I have a very good reason to keep the Kenko 2x.