Recommend a good extender for Tamron 70-300
Been using it along with my D600 to shoot birds but 300mm isn't always adequate. What are some good extenders that'll allow me to get 500mm+?-- hide signature --
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Teleconverters aren't recommended on zoom lenses. You wouldn't be happy with the IQ. If you're willing to spend some money on a prime lens such as a 300mm f4, then a TC would work fairly well to push you on out to 450mm or 600mm depending on the TC. Even at this, you still loose some sharpness.
Having said all of this, I would just crop the image to get where you want to go. The resolution of the D600 is plenty to do this with and maintain very usable IQ.