I was just wondering if anybody has used the Sigma 2x Teleconverter and the Sigma 150 - 500mm lens together? I am wanting to do some more birding but would like to extend the focal length and as I already have the Sigma lens I was thinking of purchasing the dedicated teleconverter. I understand that I will lose about 2 - f/stops of light and that I will have to manually focus.
Would love to hear any comments you may have about this combination. Thanks