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Old Apr 2, 2008, 12:29 PM   #1
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Macro question
I currently have the following lenses.
Minolta 70-210/f4 macro (beer can ?)
Minolta 28-85/f3.5-4.5 macro
Minolta 50 mm f1.7

For $500 , ( from B & H ) what will the KM AF D 100mm f2.8 macro
buy for me that I don't already have?

Regards
Furd

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Old Apr 2, 2008, 1:31 PM   #2
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Furd wrote:
Quote:
Macro question
I currently have the following lenses.
Minolta 70-210/f4 macro (beer can ?)
Minolta 28-85/f3.5-4.5 macro
Minolta 50 mm f1.7

For $500 , ( from B & H ) what will the KM AF D 100mm f2.8 macro
buy for me that I don't already have?
The 100/2.8 is faster than the beercan and the 28-85, and longer than the 50.

One of the problems with macrophotography is getting sufficient light. All too often, the camera and the photographer are so close to the subject that they block a significant portion of the available light.

If you do all your macro work in well lit enviroments, I'd say you shouldn't bother, but if not, you might want to seriously consider it.
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Old Apr 2, 2008, 1:34 PM   #3
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For one thing, you'd have the the ability to fill the frame with a much smaller subject.

Your beercan (and other similar zoom lenses) are not true 1:1 Macro lenses. For example, the Minolta 70-200mm f/4 Macro has a maximum magnification of 1:4.

That means that the smallest subject you can fill the frame with is 4 times the size of the film or sensor (and usually, the best macro ability is on the longer end of a zoom at it's closest focus distance). Note the maximum magnification column in this table of lenses (scroll down and you'll see a table):

http://www.mhohner.de/sony-minolta/lenses.php?lg=e

The 100mm f/2.8 Macro is a true 1:1 Macro lens. That means it can fill the frame with a subject the same size as the film or sensor. So, you can fill the frame with much smaller subjects without cropping with a true 1:1 Macro lens like this. It's also a very sharp lens (as are most good Macro lenses) with very high quality optics.


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Old Apr 3, 2008, 12:41 PM   #4
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Thanks TCav and JimC for the info, I just reduced B % H enventory.
Have a nice day.
Furd from the other Washington.
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Old Apr 3, 2008, 12:43 PM   #5
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Let us know how you like it and post some photos from it. ;-)

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Old Apr 3, 2008, 4:17 PM   #6
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I have a question about macro. I don't have a 1:1 macro lens but I do have a 100mm lens (100 f/2).

How would my 100mm with a extension tube work in comparision to the 100 macro?

Would it be a 1:1 macro?
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Old Apr 4, 2008, 7:30 AM   #7
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Extension tubes have their drawbacks. For one thing, you'll lose the ability to focus on further away subjects while using them. You also lose light with Extension tubes.

Given that the 100mm f/2 has a max magnification of something like 1:7.7, at a focus distance of 100cm, I'm not sure tubes would be that practical, except for infrequent use. You may need to stack multiple thicker tubes to get the equivalent of a 1:1 Macro. But, I don't have any try to with my Minolta 100mm f/2.

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