تست میدانی لتز Tamron 150-600 در سایت dpreview
http://www.dpreview.com/articles/871...usd-field-test
Super Zoom? Tamron SP 150-600mm F5.0-6.3 Di VC USD Field Test: Digital Photography Review
In the last few weeks of testing the Tamron 150-600 F5-6.3, I fielded an incredible number of questions from people about my thoughts on this lens, compared to the Sigma 150-600mm F5-6.3 DG OS HSM Sports Lens and the Canon EF 100-400mm F4.5-5.6L IS II USM. That's an interesting question because those lenses have some significant differences. The Sport version of the Sigma lens is almost twice the price of the Tamron, and the Canon 100-400 is more expensive again, and falls considerably short of both of them in terms of reach. For most fairly serious wildlife photography, 400mm is not long enough, but on an APS-C camera like the EOS 7D Mark II, the 640mm equivalent would work very well.
If you're shooting with a full frame camera, you'll be pleased to have the added reach of either of the 150-600mm options, but bear in mind that one of my favorite features of the Tamron lens was the light weight and portability. Measuring 11.4 in./29cm in length and weighing in at 6.3 lbs/2.9kg, the Sigma is nearly 50% heavier than the Tamron, and almost an inch and a half longer. Considering the generally good performance of the Tamron lens, at a price tag of nearly half that of the Sigma lens, it's hard not to recommend it
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