Sigma Lens Tests 1.4X Teleconverter

With 80400 f4.5-5.6 At 560mm (400 x 1.4)



AF will not work with the 80400. These images were shot at f8. With the 80400, the 1.4 does not do as well as with the 70200 f2.8 EX/HSM which loses very little. The letters and numbers look good although the rainbow detail is not resolved as well as with other tests. At infinity, it is difficult to focus as the combination focuses past infinity and blurs. I did several series of shots and picked the best. It may be that the sharpness of the 80400 at 400mm is not enough to add the T/C. Take a look at the comparison of the 70200 f2.8 EX/HSM at 280mm (200 x 1.4) versus the 80400 at 280mm. I need to do more shots at 560, real-life before I pass final opinion on this combination.