Skip wrote:
> Ah. Thanks. After learning about this, and then about macros, I decided to
> check out the 50mm 1.4. It looked to me like the lens focused down to about
> 18", and then I checked it in the lens book and it did say 1.5'. So that's
> not bad, I think. Not exactly as close as some of the WA macros, no. But
> still not too bad...
If you put 50mm worth of extension tubes between that 50mm lens
and the camera, you will be at a 1:1 magnification ratio. Also
called "life-size", as the film frame will record a 24x36mm
area of subject matter.
25mm of tubes gives half that, a 1:2 ratio & 12mm will give 1:4
and 100mm gives 2:1 - and so on.
Bellows are like adjustable tubes, and can usually extend a 50mm
out to a bit over 2:1 magnification.
Close focus distance gets smaller as the lens is extended further
and eventually gets physically awkward, as well as camera shake
and extremely shallow Depth of Field problems arising.
But it is much fun! and tubes make an inexpensive means of high
magnification photography (especially screwmount tubes!)
Bill
---------------------------------------------------------
Bill D. Casselberry ; Photography on the Oregon Coast
http://www.orednet.org/~bcasselb
[EMAIL PROTECTED]
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