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View Full Version : Macro close focus question


Phill D
1st June 2014, 07:54 AM
Decided to have a bit of a play with my 50mm macro today just to see if I could get some images comparable to those in the 60mm macro thread Brian started.
So I decided to check what the minimum focussing distance was. According to Olympus it should be 0.24m. On a quick test I can get the af to lock at a much shorter distance than that! It's more like 100mm rather than the 240mm Olympus state. Looking at the Oly data for the 60mm macro it's close focussing should be 190mm what do people actually get with that lens?

So the real question is what's going on here? Is my af locking but images wont be focussed? They certainly look ok after a quick check. So what is going on?

andym
1st June 2014, 08:33 AM
Hi Phil

As far as I can remember I think the focus distance on any lens is measured to the plane of the sensor and not the front of the lens. Are you taking this in to account?

Phill D
1st June 2014, 08:58 AM
Ah that would make the figures make a bit more sense, I was just taking the front element to subject distance. I still think the Olympus figures are a bit conservative though but that is probably understandable. Thanks Andy you solved my question in 39 minutes pretty impressive well done.