Ever since i went back to Canon a few years ago, ive been REALLY missing doing Macro work. I had a really nice Nikon Macro lens(105mm 2.8 VR) but have been apprehensive to blow all the cash for a Canon equivalent, which run 700-900 bucks, since its not something i use on a regular basis. So after reading the ins and outs of Macro work, Kenko Extension tubes always get thrown into the discussions and while ive never used extension tubes before, ive always been curious about them. Found a used set over on POTN for a hair over 100 bucks shipped to my door and so far, im impressed!!
The fit and finish of them are nice. They all interlock with each other, the body and the lens very tightly and feel nice and solid. Because there is no glass inside the tubes and they only act essentially as spacers, there is no image quality loss. By increasing the distance from the lens to the body, you effectively shorten the minimum focusing distance from the subject to the front of your lens. But let me tell you, the depth of field gets PAPER thin when you start stacking these tubes together! A super solid tripod is an absolute necessity if your going to use all the tubes together. There is about a 1mm difference between having something in focus and having something nowhere near in focus.
Anywho, on to the example pics. These demonstrate how close they let you get and the shortest distance i can get and still keep images in focus. All these were shot with a 50mm 1.8MKI set to F5, ISO 200. Our garden gnome was a willing subject and the point of focus was loosely the white dot on the eye.
50MM, no extension tube - Minimum focusing distance 13.5"
50MM, 12mm extension tube - Minimum focusing distance 5.5"
50MM, 20mm extension tube - Minumum focusing distance 4.25"
50MM, 36mm extension tube - Minimum focusing distance 3.0"
50MM, 12mm+20mm+36mm extension tubes - Minimum focusing distance 1.50"
CRAZY how close you can get with these things! I couldnt even begin to imagine these things on a dedicated Macro lens!
A few things i am finding with them though....with all the tubes stacked together, auto focusing is nearly impossible. Like i said before, even just a fraction of a millimeter means the difference between in focus and completely out of focus and even a pro level Canon body struggles to lock a solid auto focus because the focus depth just isnt there. Manual focusing and a tripod built like a tank is definitely the only way to go if you need super up close shots. I havent tried it with any of my other lenses but i plan on spending the rest of the afternoon playing around with these so if i take any good shots, ill be sure to post them here.
So far though, if you want to shoot Macro and want to shoot it cheap, these are the hot ticket for sure!!