As this was never formally standardised, it's pretty much up open to interpretation. Traditionally, people talked about macro as meaning 1:1 (film size to subject ie. subject is life size on the negative) or more. However, most manufacturers of equipment, apart from Nikon, have a more liberal view. I tend to see 'close up' as equalling 'macro', myself.
I see what you mean, though. Some lenses manufacturers talk about 1:3.5 being macro, which is maybe a bit of a stretch.
Chris Seary
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