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-   -   My World: Which lens for Macro? (http://www.openphotographyforums.com/forums/showthread.php?t=17826)

fahim mohammed November 24th, 2013 04:03 AM

Which lens for Macro?
 

Better than 1:1 :)

Tom dinning November 24th, 2013 04:32 AM

Is that the new toy?

fahim mohammed November 24th, 2013 11:44 AM

Quote:

Originally Posted by Tom dinning (Post 148356)
Is that the new toy?

Neither new nor mine, Tom.

Someone wanted to show me what they were seeing in a certain tissue sample of mine. Talk about macro!!

p.s. i did not understand a thing.

Dr Klaus Schmitt December 8th, 2016 10:48 PM

http://macrolenses.de

Go choose....

Doug Kerr December 9th, 2016 08:10 AM

I will take this opportunity to remind us that the infamous "1:1" image magnification, often used as the criterion of "real macro performance" for a lens, is not very definitive with regard to our actual photographic needs.

Almost always, what we are really interested in is what sized object (or object field) will fill our frame. At the "1:1" benchmark, that is a field whose size equals the fame size. For a camera with a four-thirds sensor, that would be an object less than 13.5 mm in diameter (about 2/3 the diameter of an American dime coin).

For an 8" 10" format camera, that object might be a ladies' shoe.

Best regards,

Doug

fahim mohammed December 10th, 2016 12:58 PM

Sure.

Best regards.

Dr Klaus Schmitt October 21st, 2017 05:14 PM

Quote:

Originally Posted by Doug Kerr (Post 175849)
I will take this opportunity to remind us that the infamous "1:1" image magnification, often used as the criterion of "real macro performance" for a lens, is not very definitive with regard to our actual photographic needs.

Almost always, what we are really interested in is what sized object (or object field) will fill our frame. At the "1:1" benchmark, that is a field whose size equals the fame size. For a camera with a four-thirds sensor, that would be an object less than 13.5 mm in diameter (about 2/3 the diameter of an American dime coin).

For an 8" 10" format camera, that object might be a ladies' shoe.

Best regards,

Doug

Ehemm Doug, sorry, but at 1:1 the object size is identical to the size on the sensor, i.e. a 1mm object will be exactly 1mm on the sensor. It has nothing to do with sensor size nor field size, it is a parameter of the lens only.

Asher Kelman October 21st, 2017 06:25 PM

Klaus, is he starting from the standpoint "where we have no units of measurement", just some camera. In that world one could say that a 1:1 image that fills sheet of film is that size too.

Asher

Doug Kerr October 21st, 2017 07:22 PM

Hi, Klaus,
Quote:

Originally Posted by Dr Klaus Schmitt (Post 180547)
Ehemm Doug, sorry, but at 1:1 the object size is identical to the size on the sensor, i.e. a 1mm object will be exactly 1mm on the sensor.. . .

Quite so.

Quote:

It has nothing to do with sensor size nor field size . . .
Quite so.

Quote:

. . .it is a parameter of the lens only.
Quite so.

Now, all that having been said, if we are operating at a magnification of 1:1, and our frame size is 36 mm 24 mm, then the size of the object field (at the object distance for which the magnification is 1:1, at which distance we presumably are focused) will be 36 mm 24 mm, for the very reasons you cite. If our frame size is 11 in. 14 in., then the size of the object field is 11 in. 14 in.

And my point is that if macrophotography is to be thought of as the photography of small (but not microscopic) objects, I don't consider an object that occupies most of an 11 in. 14 in. region "small".

Best regards,

Doug

Dr Klaus Schmitt December 3rd, 2017 05:39 PM

Absolutely Doug, I just wanted to be clear. Surely, there were lenses built for shipbuilding drawings which copied 1:1, not what I woudl call "m,acro" rather than "repro"

Doug Kerr December 4th, 2017 08:07 AM

Hi, Klaus,

Quote:

Originally Posted by Dr Klaus Schmitt (Post 181282)
Absolutely Doug, I just wanted to be clear. Surely, there were lenses built for shipbuilding drawings which copied 1:1, not what I woudl call "m,acro" rather than "repro"

Of course.

Best regards,

Doug


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