The photographer, Thierry Legault, has updated his page
and is telling a bit more about how he took the shots and added new photos.
There's also a little question and answer part at the end of the page.
Here's what's most interesting to me:
The transition time was only 0.8 seconds and he managed to get the shots at a speed of 1/8000 at ISO 100 using continous shooting blindly (one cannot see the shuttle on the camera's viewfinder) for 16 shots in 4 seconds. The first photo starting two seconds before the expected "arrival time" in front of the Sun.
Getting to know these additional info made me even appreciate his pics more.
You should check out his sturdy tripod in the pictures he has added. Knowing only photo camera tripods this one is a bit bigger.