1.4 or 1.7 I use these on my 300 F4 but wouldn't want the old 2x.
The new one is supposed to work on it but at almost twice the price is not for me, well not until I see some results from it
Just found the 2x MKIII TC, anyone any experience of that?
Way more pricey than the MKII versions, roughly £450 compared to £300.
Latest version, only been out a few months, doubt there are any in the UK, supposed to be very good
Would not suggest you got one for your f4, would become an f8 and I doubt AF would work, stick to the 1.4 or 1.7 on that lens![]()