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Originally Posted by Roy C
Changing the subject slightly but can the experts tell me the difference between the 'focusing distance' and the 'working distance' when using an extention tube.
As an example I have seen a table that uses a 12mm tube and an 50mm 1.8 lens that gives a focusing distance of 249-324mm and a working distance of 156-239mm- how are these figures arraived at.
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Hi Roy,
I thought this may be easy. 12mm tube and 50mm and tape measure I have so.........
With lens set at nearest focus 0.45m end of lens to in focus point ( lens to subject distance ) 125mm.
With lens set to infinity end of lens to point in focus ( lens to subject distance ) 190mm.
At the start of the tape focus 0.45mm to infinity ( focusing distance ? ) 65mm.
I now don't understand the numbers in the quote.
Don