Its a good comparison and then we come into DOF etc so it may be benificial to use tubes when more structure is needed. I think mine is good at Micro camera workSince we're talking tubes and TCs, I decided to see what mine could do. Here's my D600 with a 1.4TC, about 68mm of extension tubes using a 105mm 2.8G. I was too lazy to get my flash out. No cropping of course. It gets pretty good magnification but not nearly as much as Scotts. The second pic is just the tubes with no TC.
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