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Old 04-05-07, 10:46
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Gidders Gidders is offline  
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Quote:
Originally Posted by Saphire View Post
Yesterday I had the opportunity to try out a true Macro lens a sigma 105mm, I was very impressed with the build and ease of use. Today I took some photos of the same flower with my cheap alternative the Canon 75-300 with the 13mm and 31mm ext tubes. It is a little harder to focus than the true macro but I am quite impressed with the results although there is a lot less DOF. There has been no sharpening done on either of the photos its as they came out of the camera, cropped and saved.

Left photo. Sigma at F8 1/60s
Right photo. Canon 75-300 13mm+31mm F7.1 1/125s
I like the second one better - the lighting on the first is very flat - was flash used? Also I'm not convinced that there is much difference in the DoF and in fact assuming that they were taken at the same magnification/size in the viewfinder this article on DoF confirms that DoF is independent of focal length and is just a function of focusing distance and aperture.

I'd be interested to know how close that extension tube set up enables you to get compared to the ture macro lens - can you post the full frames of both for comparison?
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