The 6D is Canon's version of an entry level Full Frame body. A FF version of your T3i, if you will. Although the 6D is a more robust camera and other features that come will it being a later design. The EOS 5D Mk III is a nearly full on professional camera. Do you need or require that level of equipment? Canon EOS 5D Mark III 22.3 MP Full Frame CMOS with 1080p Full-HD Video Mode Digital SLR Camera (Body) Canon DSLR Camera [EOS 90D] with Built-in Wi-Fi, Bluetooth, DIGIC 8 Image Processor, 4K Video, Dual Pixel CMOS AF, and 3.0 Inch Vari-Angle Touch LCD Screen, [Body Only], Black .

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