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02-05-2011, 11:18 PM   #1
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Macro + DOF experiment... surprising results!

Hi everyone, so today I tried to compare 2 macro set-ups of mine.

1) 100mm f4 bellows takumar with around 100mm extension tubes


2) tamron 90mm 1:2.8 di sp macro.

Here are the two images taken of the same subject, with both lenses set at f/11:

full image:

100% crop:

Bellows Takumar:
full image:

100% crop:

So the surprising results are that the 4 element bellows takumar annihilates the di sp macro! It has more magnification with the tubes, while at the same time better quality of image and way larger DOF!

If someone could explain to me why the DOF varies so much, I would be appreciate it as I am a bit surprised by this.



02-05-2011, 11:27 PM - 1 Like   #2
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Easy--you shot the Tamron at f2.8--that's what the EXIF shows. Also, a flash will indeed make a difference in how things appear, and can give added definition even if they were shot at the same aperture. Please retest this--I'd really love to see the results (I'd expect the Takumar to still outperform the Tamron as it's a slower lens and thus probably won't have sharpness decay as much at f11 as the Tamron)!
02-05-2011, 11:46 PM   #3
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haha, whoops! been playing with old manuals too much. Retest incoming
02-05-2011, 11:52 PM   #4
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Tamron at F11 this time using AV mode... not M


And a different, but better crop due to slightly different lighting:


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