As this is a "cheap and easy" way to do it, there are some drawbacks;
There will be no autofocus, and the DoF (Depth of field) is very very shallow.
Step 1: What you need.
I am using a lens from a Canon 1000f, I picked this up for about £10 (camera included)
and this lens is ideal as there is no need to unscrew anything.
And any scalple, x-acto knife, craft knife blade will do.
Step 2: Removing faceplate and Focus ring
Some gentle prying around the rim will get that off.
Then grab a hold of the lens and turn the focus ring anti-clockwise and it should detatch.
The great thing about this is that you can leave the information ring at home, and the focus ring easily screws on and off so you can keep it with you and use it for normal shots and macro when you're out and about!
Step 3: Final step
That's it you're ready to go!
You will need to have about 3cm between the lens and subject to get a clear picture, anymore either way will cause your image to be barely recognizable.
The photos here are
1. As close as I could zoom and get focus at with standard 80mm.
2. Macro'd at 35mm
3+4. Macro'd at 80mm
As this is a zoom lens, using it at 30mm will produce a nicely enlarged image, and using it 80 will greatly enlarge it again, though be warned, you compensate DoF for size ( the more you zoom the narrower the depth of field will become)
That's everything, thanks for reading my first instructable, feel free to leave comments!
Also if you know of any other lenses with this detatchable focus ring, let me know and I'll add it in!
Happy shooting :)