Canon 500D diaopter with a Canon 70-300IS.
A good macro lens will set you back hundreds of pounds - plus its yet another lens to hoof around in your backpack. Macro photography was something that I have a passing interest in - there are rare occasions when I could make use of a macro lens - but nothing to justify splashing out on one just yet. I stumbled on a reference to the Canon 500D on a Nikon user webpage of all places - using it in combination with a 70-200 VR and reporting very good results.
So what is it ? Its simply a large, thick filter which screws onto the lens in the same way that a polariser or UV filter does and allows your lens to focus much closer to a subject essentially converting your telephoto zoom into a macro lens. There is no loss of light and despite what logic would dictate when you stick extra glass between the subject and the lens I've not been able to discern any noticable loss of sharpness or colour.
I used this extensively in combination with Canon's 70-300IS. Currently no manufacturer offers a image stablised macro lens thus necessitating the use of a tripod. Due to the shallow depth of field which occurs at the high magnifications when using the 500D you will find yourself working at large slow apertures - most of the time at least F16. Having a light, sharp, image stabilised lens is vital to getting sharp handheld closeup images. Focussing is manual although I found autofocus did work. The recommended technique is to set focus at infinity and move closer / further away from the subject until focus is achieved. However when working with such shallow depth of field it makes more sense to manually focus so that you can get exactly what you want sharp. The small viewfinder of the Canon xxxD series of cameras makes this hard - its a much easier task with the larger brighter viewfinders of the xxD and xD series. The shallow depth of field isolates subjects in a way which to my eyes nis very pleasing. The image below of Jack-by-the-Hedge was taken on a bright sunny day. The flowers are sharp - but the sunlit grass below is gone and the rest of the plant a lovely faint green blur.
There's really not much more to say about this combination - except that it works very, very well. All of the close-up images in my wild flower were gallery were taken with it and I'm personally very happy with the results. If you own the 70-300IS then the 58mm 500D is a relatively cheap accessory - and a fraction of the price of a true dedicated macro lens. The IS and light weight of the combination make handheld close up shots a reality.
I've since picked up a 77mm 500D for use with the my "L" lenses although I haven't had much opportunity to use it. Inital experiences suggest that it works well with the 100-400 (giving obvious better magnification although true macro 1:1 doesn't occur until 500mm) although due to the weight of the lens and bigger diaopter a tripod (or beanbag depending on the situation) is required. I might finally have found a use for live view as a focussing aid as well. I suspect a macro focussing plate which allows you to move the lens whilst the tripod is static will be useful as well. Handholding with the 24-105 in good light also gives good results and one I want to really investigate once spring properly kicks in.
Pros : Cheap, cheap, light and does exactly what it says on the tin. A no brainer if you own the 70-300 IS (or equiavlent).
Cons : Manual focus. Doesn't offer true 1:1.
Conclusion : A great way to get a stabilised macro lens. Works brilliantly handheld with the 70-300IS.