80d with 1.4 teleconverter

I have an 80d with a Tamron 600mm G2. Anybody have any experience with this combo using either a Canon or Tamron 1.4 teleconverter esp. for birds in flight. Thanks

I have an 80D with the Canon 1.4x (mark 2). The extender protrudes into the lens cavity, I don't think you can attach the Tamron lens to it.

I use my extender with the the Canon 300mm f/4 L ... it slows the focus speed down. I don't shoot too many birds in flight, so I can't speak directly to that. I'm sure it would work, but the focus is definitely slower while using it.

I tried this lens with a Tamron 1.4 teleconverter on a Canon 7D Mk ll which like your 80D also has f8 auto focus. I found that the combination would only AF in the brightest light and even then would be slow and at times unreliable. In other light it would hunt for focus and at times it would not do anything. I also found that there was little or no difference in quality between using the TC or just cropping. My advice would be to save your money and use the G2 as it is. To answer your question about birds in flight the answer is a definite no,way to slow. I hope this helps.

I would not bother. I got good results with Sigma 150-600 S and 1.4 TC for perched birds. For birds in flight, waste of time.
The Tamron is communicating f8 with the 1.4TC but it's really f9.

'Affordable' 600mm is a fairly recent development and you have it. Next stop megabucks.