blair1955 wrote in post #16180701
This may have been asked already but I want a 1.4 converter that will work with my Tamron 70-300 f/4-5.6 Di VC lens and don’t know which brand to get. Also how much weight can the mount on my 60D take? I don’t want to over stress it.
Weight wise, I'd think you'd be absolutely fine with the mount - a 1.4x TC isn't that big, and I don't believe there's any reason you couldn't put one of the monster telephoto primes on the 60D. I believe the Canon 70-200 f4 IS L is about the same weight as the Tammy, and my other half happily uses that + a 1.4x TC with a 60D.
I suspect you may have to avoid the Canon ones - certainly the version III models have a protrusion, and it won't fit into the back of the Tammy.
TBH though, you may want to consider if it's the right thing to do; the Tammy is a great lens for the money, but it's not stellar at the long end, and a TC will only make that worse. With a 1.4x TC you'll be at f8 at 300mm for AF (which means manual focussing on the 60D - unless you trick the camera into thinking the TC isn't present, but it's still unlikely to work well). You'd probably also want to stop down once more to help the quality, which means you'd need to shoot at f11. In short - I'd definitely recommend borrowing or renting a TC first, as I have a feeling the results on the Tammy won't be worth the purchase cost of a decent TC.