LAST EDITED ON Aug-07-01 AT 01:53 PM (GMT)
Actually Tad, the Kenko AF extension tubes maintain metering. I don't have any experience with bellows, though.
I don't know what your financial situation is Dave, but I always start with the least expensive path to quality results, although this sometimes requires a little more intervention from the user. After looking at your profile, I would recommend a good 2x converter, a 7 element design, which is usually around 100USD, I think, and hook it up to your 70-300 in macro mode. (The converter also can be used for telephoto use, which extends its usefulness. Stick to f8-f16 for sharpness though.) Use Aperture priority, f16. Of course, you will need to use flash.
If you don't already have a flash, consider an all purpose unit and an SC-17 cord. (Again, you get more usefulness across the board.) I don't know what the closest focus distance of your lens is, but if it's at least a foot or so you can use the flash in the hotshoe, or even the built in flash if the film speed allows it. Remember, f16 with a 2x converter requires the same light as f32 without a converter. The off-camera cord allows you to hold the flash in one hand and move it around for the most effective, or creative, angle.
If money is no object, or macro is your only interest, definitely go with a macro lens. ---scott
Wood Sorrel; N60, 105mm Micro, SB24 held above and behind the flower.
"I am always doing that which I cannot do, in order that I may learn how to do it."