Lens choice? 400f/5.6 (edited) or 150-600

I'm looking to add another lens. I already 70-200/f4. Looking for more reach. Looking at the canon 400f4 or the 150-600 non g2. Will be used on a 1Dm4. also thinking getting a 1.4 extender. Be used for birding mostly and some wildlife.

Atrawick wrote in post #19005828
I'm looking to add another lens. I already 70-200/f4. Looking for more reach. Looking at the canon 400f4 or the 150-600 non g2. Will be used on a 1Dm4. also thinking getting a 1.4 extender. Be used for birding mostly and some wildlife.

Could you clarify two things for me.

- What subjects are you shooting? Where?

- Are you comparing the Tamron zoom to the Canon EF 400mm f/4 DO ?

southeast alabama, mostly birds right now, sorry the 400 is 5.6 instead of f4. my bad

That sounds like a more realistic choice.
400 5.6 is lighter and AF will be faster and more consistent.
The zoom zooms! Benefit is obvious. All 150-600 options are stabilised.
I'd consider Sigma 150-600 C over the Tamron. More options for customising AF and OS.
The OS also has a better implementation IMHO.

If you wanted to specialise or shoot a lot of birds in flight I'd go with the Canon. Otherwise get a zoom.

Atrawick wrote in post #19006124
southeast alabama, mostly birds right now, sorry the 400 is 5.6 instead of f4. my bad

Im selling my canon 400 5.6 if your planning to go that route?

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