I use a Nikon AF Nikkor 70-300 mm lens. Will a Teleconverter x2 boost it up to 600 mm?
Yes, but at great cost of light and clarity. And if you can find one thats compatible. Nikons are not.
Don't bother. You are unlikely to be happy even it you can find one that fits.
You can kiss autofocus goodbye.
if you can try before you buy you might get lucky.
i never use auto-focus with a 200 or 300mm lens and converter anyhow.
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