I've had some decent success with a 1.4 TC on my Nikkor 300mm f/4. In a trained set of hands (I.e., not mine) it can be an exceptional combination. All shot with my Nikon D7100. Great for BIF too if you can close the distance; pretty light and easy to move!

[Linked Image]DSC_2231LR4edited-2 by kipmichael, on Flickr

[Linked Image]DSC_3469LR4edited-2 by kipmichael, on Flickr

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DSC_9710LR4edited by kipmichael, on Flickr

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