At this point attach the lens to a camera and power it up. Set the lens on MF and turn the focus ring until the floating element is fully forward as shown in this shot. Turn off camera and remove lens.After removing the indicated circlip the focus lens will slide out of it's cell for cleaning.
The rear lens barrel (containing all of the electronics) can be unscrewed from the front lens barrel after loosening the set-screws hidden under the manual focus ring. Slowly turn the focus ring while looking through it's access hole to locate then loosen the underlying set-screws. Note that the lens is tapped in four places for four set-screws. In my lens at least, only two of these threaded holes actually had set-screws in them.
You can loosen the 6 front barrel set screws and use a lens spanner wrench on the front element to remove the entire front inner barrel. Conversely, you can tighten these 6 set screws securely and use a lens spanner wrench to remove the front protective element only without turning the inner lens barrel.
Loosen the 12 set screws in the retainer ring for the tripod mount sleeve.Unscrew the retainer ring by turning counter-clockwise just like the beauty ring.The tripod mount sleeve will now slide off of the lens to allow access to the set screws for the front inner lens barrel.
Remove the detente screw and the underlying spring and ball. This screw has a square shoulder so if you don't have the correct tool you can use vise-grips or pliers to remove it.
Remove the 4 screws and the tripod foot.
Loosen the 4 set screws and screw off the beauty ring counter-clockwise. You may need to tape the beauty ring to the tripod mounting ring and turn both together to get a good enough grip to break it loose and get it started turning.
In order to clean the back side of the front protective glass element you will need to pull off the protective rubber ring around the front of the lens. You will also need to verify the front barrel set screws are either tight - to remove the front element only, or loose to remove the entire front inner barrel from the front outer barrel. In order to access these front barrel set screws the tripod mounting ring must be removed.The next few images will show the steps necessary to remove the tripod mounting ring allowing access to these set screws. If you only need to access the focusing lens you can skip these steps and proceed to the image of the rear set screws.
Mike Ronesia: Nice, how many tries did it take?
I would guess about 500 rounds were fired while the the camera was shooting at 8 FPS. Thousands of frames were captured in the process. This image is solely due to persistence and luck. With the camera shooting 8 FPS the chances of catching the bullet within 6 inches of the barrel is about 1 in 212.
old_slowhand: interesting, did you use an acoustic trigger? perfect timing, anyway.
No acoustic trigger was used. Even if the sound was detected instantaneously the shutter lag of 40ms would allow the bullet to travel 34 feet before the shot could be captured by the camera.
Thanks everyone for your kind comments. You may also be interested in 2 more similar shots I've entered in the "Fast Movement shot for anything" challenge.http://www.dpreview.com/challenges/Challenge.aspx?ID=6915