I bought a Canon 100mm macro F2.8L USM IS lens second hand on eBay earlier in the week. I have been thinking about upgrading from the non-L version for some time and finally bit the bullet when I managed to win an auction at what I thought was a pretty reasonable price. The lens arrived very quickly and seems to be in good, fully working condition. Anyway, I have both lenses at the moment whilst I decide what to do with the non-L lens (sell it on eBay?).
I have looked at a number of comparative reviews and most agree that there is not a lot to choose between these lenses in terms of image quality. The L version turns in a slightly higher MTF rating, but both are very good. The L also has a 9 bladed iris and turns in slightly more pleasing bokeh. However, the L lens has Image Stabilisation and the usual L-series sealing against weather and dust. After talking to a number of other people with the L lens or with Sigma macro lenses with IS, I am convinced that this facility is worth having!
Anyway, it was a nice sunny afternoon, so I rushed out into the garden to try them out on the same subjects and in the same lighting. These pairs of images were been treated the same way - cropped to the same size and then rescaled to the same extent for the web-site. I haven't done any sharpening on any of them.
Here is a male
Helophilus pendulus that was hanging about the pond, perching mostly on fallen leaves from a nearby
Acer that were floating on the water surface. These were taken using available light with the camera mounted on a tripod and focussing rail. The exposures are the same: F11, 1/125, ISO400.
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| Canon 100mm macro F2.8L USM IS |
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| Canon 100mm macro F2.8 USM |
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These shots of the Garden orb-spider
Araneus diadematus (I think the wrapped up prey item is a bee) were taken rather later on when the light was fading, so I used flash. Again, the camera was mounted on a tripod and focussing rail and a Yongnuo YN565EX flash positioned to the right and above the spider with a reflector (a piece of white foam core board) held as close a possible on the opposite side. The exposure was F22, 1/250, ISO100 with -2/3EV flash exposure compensation dialled in to avoid burning out the cross marking on the spider's back.
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| Canon 100mm macro F2.8L USM IS |
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| Canon 100mm macro F2.8 USM |
The next pair are 100% crops of shots of flies resting on the garden shed roof in the evening sunshine. They were both taken with the camera on a tripod and focussing rail using manual focus with the magnification set to 1:1. These were taken a few days apart and so the exposures are not exactly the same. The top one is a Blow fly (
Lucilia probably
sericata, Calliphoridae), the bottom one is a Flesh fly (
Sarcophaga, Sarcophagidae):
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| Canon 100mm macro F2.8L USM IS (F11, 1/8, ISO100) |
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| Canon 100mm macro F2.8 USM (F16, 1/4, ISO100, with mirror lock-up) |
I don't see much difference in image quality between the two lenses. It is possible to discern some additional sharpness in the leaf surfaces underneath both subjects and the eye facets and bristles of the two flies from the L lens.
