I just managed my first APS macro shot of something I saw on the window that looked to be worth a shot. I usually use M 4/3 but focus is tricky. I can get a magnified view of an insect but not all of it if I fill the frame. I can magnify to a level where I see at the actual camera pixel level but trying to frame that or even keep it similar is nigh on impossible. There are some spider shots in one of my flickr albums taken like that using a old manual pentax macro lens on an adapter. Loads were thrown away. My hit rate with m 4/3 is a lot better. Take 3 and chances are at least 1 will be ok.
It was at a height of 7ft plus so the gear was rather difficult to use due to weight.
I'm mostly posting due to noticing that diffraction effects had been mentioned. There are a couple of things that explain why this isn't as important in practice. The lenses are not diffraction limited for a start so diffraction tends not to be the over riding factor. The lenses aberrations are. Diffraction can add to those and make them "worse" if that is the correct word by spreading the lens problems out a little. The main effect is loss of contrast which can be fixed. As the aperture is closed down more they begin to behave more like a real diffraction limited optic. Wide open nothing is remotely like a diffraction limited optic, not camera lenses anyway. It's nigh on impossible to do that when many pieces of glass are needed for the optics.
The shot was taken hand held at 1/400th at F16 with high speed flash in high speed mode. The spider may have spanned 20mm. So 1:1 wouldn't fit so it's some where around 1/2 to 2/3. I couldn't get any closer. This is a crop of the full sized image from a jpg. Raw might be a touch better but only down to improved contrast really.
I used F16 because I couldn't be certain of keeping the camera distance dead constant. Not that it gives much margin.
John
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