I'm no expert, but I would guess that the focusing group inside the 90mm is much bigger and heavier than the one inside 10-18mm.
I considered getting an s-Turtle, but decided to wait for the UW-Technics trigger to come out. Pavel Kolpakov has posted on Wetpixel that it's planned for the end of May - not too far away now.
I considered getting an s-Turtle, but decided to wait for the UW-Technics trigger to come out. Pavel Kolpakov has posted on Wetpixel that it's planned for the end of May - not too far away now.