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Canon RF 800mm f11 vs Sigma EF 150-600 (C or Sport) w/ Sigma 1.4 TC (1401)


Has anyone taken a close look at the image quality and usability(focusing etc) of the Canon 800mm f11 vs the Sigma 150-600's with the 1.4 TC? I own the Sigma and am considering the 800 as a lighter native RF option with an EOS R. 

thanks in advance



Not much of choice, IMHO.  RF 800 is a better choice.  You will not have edge to edge AF points, but you should get much better performance over the Sigma.

"The right mouse button is your friend."

Thanks.  What would your choice be assuming a budget of around $2500?

BTW, it appears that most focus points are available with the Sigma and the TC-more than the 800 RF f11



For that budget, I’d trade in the EOS R for an R6 and the RF 600mm or 800mm.

"The right mouse button is your friend."


I'm holding out for an R5 or , hopefully, R7.  I shoot a lot of birds and have to crop. At least the R5 in crop mode would be close to 20mpx before cropping. 


I can only comment on the 150~600C and 1.4x TC which I own also.  Its a very nice lens / combo.  

I agree with wadizzle's thought process.  No reason to upgrade to a Sigma S since you are already using an RF mount and plan to continue in that direction.  Nothing wrong with a control ring adapter, but if your body is RF there is no reason not to go with RF mount glass moving forward.

This will hopefully (and finally) be a better year for mirrorless.  R3 kicked it off.  R5c shortly (announcement anyways) and R7~R9 also coming.


Bay Area - CA

~R5 C ( ~RF Trinity, ~RF 100~400, ~RF 100~500, +RF 1.4x TC, +Canon Control Ring, BG-R10

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Thanks Rick 

Definitely holding out for that crop sensor R body camera.  If that doesn't happen within a year, I'll probably go with the R5.  I'm just not sure about R6 20mpx considering the cropping I do for birds. I know that's a great sensor---but.

I'm very happy with the Sigma C and TC combo.  Much better than I'd imagined and even better on the EOS R body.  I never did do any micro adjustment on my 6D II. I'd love to move to the Canon RF 100-500 with TC , but man is that pricey right now.


"I'm very happy with the Sigma C and TC combo."

I am or was an owner of all the 150-600mm super zooms. Tamron, Tamron G2, Sigma C, Sigma S.  I have since sold off all but the Sigma Sport. It is my goto favorite super zoom lens but the difference in IQ between it and my C was so insignificant to almost be nonexistent. The Tamron G2 is probably your best of the bunch if IQ is your manin most thing.

I personally do not like any tel-con on any of these lenses and don't recommend it to anyone else. But if you must use the same brand tel-con as lens manufacturer. 

"Canon 800mm f11 ...."

Again, personally I would not buy any f11 max aperture lens especially if a tel-con was being considered. It just too great of a handicap to start right out of the gate. There is always a great debate as to whether adding a tel-con or simply doing a crop in post is best. Using a tel-con and also doing a severe crop in post has to be the absolute worst case, again, IMHO.

EOS 1DX and 1D Mk IV and several lenses!

Yes, TC and cropping is no good.  I do have the Sigma TC for the 150-600 and the Canon 1.4 iii extender I use with the old Canon 400 f5.6.

I really was never too happy with the results of either of them on my 6Dii or 80D, but I have to say I'm getting some pretty usable images using the EOS R with the adapter..

I just rented the 800 f11 and it's actually OK.  Not horrible in morning and afternoon light and images clean up pretty well with Topaz Denoise, but definitely would not use a TC with it.


"Definitely holding out for that crop sensor R body camera."


Here again it will depend highly on the sensor and not the crop vs FF difference.

EOS 1DX and 1D Mk IV and several lenses!