a good Marco lens

Hello surveygrrl. First, I want to clear up something before making any recommendations... When talking about macro photography (and I am not talking about some vague notion of macro that lens makers sometimes refer to when they mean "somewhat closer than your average lens", I am talking about true, dedicated macro), what makes the subject bigger is not the "mm", it is the "magnification". True macro means at least a magnification ratio of "1:1" -- that is, the subject is just as big on the imaging sensor (or film) as it is in real life. Thus, on an APS-C sensor that is about 24mm wide (like the ones inside Canon Digital Rebels and EOS 10D/20D/30D/40D cameras), a bug that is 24mm wide would fill exactly the picture's frame. Magnification is sometimes also presented as a decimal number, such as, for example, 0.25x (which would in fact mean a ratio of "1:4", typical of non-macro lenses). So a true macro lens has at least a magnification of 1. Some magnify even more. That being said, the "mm" will not have an effect on how enlarged the subject will be, it will have an effect on the focusing distance (how far you have to stand from the subject in order to obtain a 1:1 magnification). The more the mm, the farther away you can stand -- but it also means that it is harder to stand still without camera shake getting detrimental to image quality. Some macro lenses require you to be so close to the subject that it is harder to work (for example, without scaring bugs away) -- a problem that you face when using extension tubes. Longer lenses (more mm) also means that the bokeh (the quality of the "out of focus" portion of the image) will be more diffuse, less of a distraction (that is a good thing). Aperture on macro lenses vary, but often, serious macro work is done using a tripod, so it may not always be such an issue. Moreover, since the depth of field in large magnifications gets very thin, you may want to close down a couple of stops anyway to obtain the desired effect. I cannot comment on third party lenses, since I do not know them very well. Canon has a couple of macro lenses, as shown here: http://www.usa.canon.com/consumer/controller?act=ProductCatIndexAct&fcategoryid=155 If you are on a tight budget and use a cropped sensor camera body (such as Digital Rebels and EOS 20D/30D/40D), you may want to consider the EF-S 60mm. At the other end of the spectrum, if you want to make a career out of macro photography, the most serious lens for this kind of work is the EF 180mm (pros use this one, very pricey, heavy, slow focus -- very over the top if you are just an amateur/enthusiast). The good compromise is the EF 100mm, which is only a tad more costy than the EF-S, but is a very excellent lens (I own one of those and highly recommend it) that gives you a decent working distance from your subjects while doubling as a wonderful prime medium telephoto lens. The MP-E 65mm is a very special macro lens which offers a magnification of 5:1 (a stunning five times bigger than "real-life"). Unfortunately, it can ONLY be used to do macro: it does not focus to infinity, like the other lenses. It is a specialty lens that requires dedication and proper lighting, etc. I hope that helped...

I was browsing the net the other day (when don't I do that?? LOL). ANyway, I found a really good photography website. I will try to refind that link and send it to you. It had all kinds of tips and tricks, and I think you would like it.