CHF443.–
Canon EF 2x III teleconverter
Teleconverter, Canon EF
Question about Canon EF 2x III teleconverter
Can this converter also be used with the Tamron 18-400 telephoto lens, which has a Canon mount?
No. Teleconverters from camera manufacturers only fit a few top lenses from the manufacturer and never for lenses from other manufacturers. A 2x teleconverter on a low-light zoom like the 18-400 is completely pointless anyway, but beginners always ask this question. This would result in an ultra-dark zoom with miserable image quality.