Some test shots on hummingbirds with this lens wide open in f/4.5 in using the lens alone without the gun stock. This lens is the most difficult lens that I have used

• Due to blades in manual diaphragm, I can't confirm focus at f/8.0 and bigger apertures.
• The focusing knob is underneath the lens barrel.
• The preset ring serves as a cocking mechanism for the lens.
• Once cocked, the aperture is wide open, slighter wider than f/4.5, maybe f/4.0, and I can focus but the catch is having to rely on the gun trigger to stop down the lens
• Without the gun stock, I can still stop down by tapping the diagram release bar underneath the lens barrel

#1



#2
shadow and too dark to freeze the motion




#3
user focus error
again a bit too dark




#4




#5

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