Canon EF 600mm f/4 III with Canon extender 1,4 III?

How is the IQ of this combo? I'm trigger happy on a 1,4 III extender from Canon but had som really bad experience with the IQ of the EF 70-200 f/2.8 III with the x2 extender (version III) from Canon. The images were almost unusable, had to stop down to around f/8 on 200mm (400mm) to get decent sharpness.
I can't find any sample images of the 600mm III and the Canon x1,4 III combo.

Is there any degradation to the images, is it noticable? Really like to know before I buy the extender.
 

AlanF

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How is the IQ of this combo? I'm trigger happy on a 1,4 III extender from Canon but had som really bad experience with the IQ of the EF 70-200 f/2.8 III with the x2 extender (version III) from Canon. The images were almost unusable, had to stop down to around f/8 on 200mm (400mm) to get decent sharpness.
I can't find any sample images of the 600mm III and the Canon x1,4 III combo.

Is there any degradation to the images, is it noticable? Really like to know before I buy the extender.
Get it - it's a really good extender. There is some copy variation with it - I've had three, 1 bad and the other two really ggod.
 
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AlanF

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Thank you, they both look horrible. It's really degrading sharpness a lot. I'll survive at 600mm :)
On the the 600mm II it works great - see the comparison here.

I don't trust the-digital-picture.com and always try out for myself. For example, he has the 400mm DO II softer than the 100-400mm II, and even worse with 1.4xTC, and I can tell you first hand that is rubbish. He put me off buying the 400mm DO II, but fortunately I did try one for myself. Get one on sale or return.
 
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On the the 600mm II it works great - see the comparison here.

I don't trust the-digital-picture.com and always try out for myself. For example, he has the 400mm DO II softer than the 100-400mm II, and even worse with 1.4xTC, and I can tell you first hand that is rubbish. He put me off buying the 400mm DO II, but fortunately I did try one for myself. Get one on sale or return.

Oh, thank You Alan.
I see that the version II is a lot sharper on that test. Well. I'll think about it, it's rather expensive here in Sweden, going for approx. $550
 
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AlanF

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Oh, thank You Alan.
I see that the version II is a lot sharper on that test. Well. I'll think about it, it's rather expensive here in Sweden, going for approx. $550
I am sure that if you buy on-line you have 14 days to return it if you don't like it. Our best dealers allow up to 30 days, and I think Canon Europe accepts returns without quibbles for 30 days.
 
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StoicalEtcher

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If you're getting/got the 600, then I'd go for the 1.4x too - it's not much more ..... :)

I've got both 1.4x and 2x (both mk iii) - and while I can't speak for how they work with the 600, I use them on a 500 f/4 ii, and for me, and my versions, the 1.4x is definitely better than the 2x when it comes to both IQ and focus speed, so I wouldn't let your past poor experience with the 2x put you off the 1.4x.

Good luck!
 
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AlanF

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I wondered if the new lens design with the larger elements moved back and made smaller to lower weight has caused problems with using extenders. The Sony 600mm has the same design so I checked that on TDP. Its performance with TCs is uperb so I wonder if the RF 600/4 + RF 1.4 will be better than using the EF 1.4xTCIII.
 
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I wondered if the new lens design with the larger elements moved back and made smaller to lower weight has caused problems with using extenders. The Sony 600mm has the same design so I checked that on TDP. Its performance with TCs is uperb so I wonder if the RF 600/4 + RF 1.4 will be better than using the EF 1.4xTCIII.

Cool, (I didn't know Sony made lenses) But it might be the same. I'll survive using "only" 600mm no biggie. I don't want to pay $550 to no use.
 
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RGB49

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I have the EF 600 iii and the 1.4 iii and the IQ is just great. I now use it on the R5 and quality wise is seems even better than when used on the 5dMK4, whether this is down to my ability to fine tune the AFMA I don't know. I also have the 2Xiii but found this quite soft on the 5D MK4 and using it on other lenses as well so I might just have a poor copy, and consequently have left it in its bag. I suppose I should give it a thorough test on the R5 to see if that is the case.
Bottom line no hesitation in using the 1.4 on a 600mm
 
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AlanF

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The EF 2XTCIII does degrade image quality more than the EF 1.4xTCIII (about a 30% drop in MTF rather than 10% for the 1.4x), and you can see it in many tests on-line, the Canon MTF charts and in my very limited experience. The new RF TCs have a different construction from the old EF, and my very limited experience is that the RF 2x is much better. Here are the design cross sections. One thing remains the same - they are overpriced for what they are.

Extenders copy.jpg
 
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SteveC

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The EF 2XTCIII does degrade image quality more than the EF 1.4xTCIII (about a 30% drop in MTF rather than 10% for the 1.4x), and you can see it in many tests on-line, the Canon MTF charts and in my very limited experience. The new RF TCs have a different construction from the old EF, and my very limited experience is that the RF 2x is much better. Here are the design cross sections. One thing remains the same - they are overpriced for what they are.

View attachment 198023

So imagine this (while cringing). Put the RF 2.0 onto your camera. Then an EF-RF converter, then the EF 1.4 and whatever EF lens on.

Somehow, I doubt that would work.
 
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So imagine this (while cringing). Put the RF 2.0 onto your camera. Then an EF-RF converter, then the EF 1.4 and whatever EF lens on.

Somehow, I doubt that would work.

I haven't thought of that. I have the R5 with a RF to EF adapter as well. That isn't a good idea perhaps? Or does it matter regarding IQ to have the RF/EF adapter and then a 1,4 extender or is it identical as with a native EF mount-camera?
 
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SteveC

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I haven't thought of that. I have the R5 with a RF to EF adapter as well. That isn't a good idea perhaps? Or does it matter regarding IQ to have the RF/EF adapter and then a 1,4 extender or is it identical as with a native EF mount-camera?
I honestly don't know, but it sounds crazy. For all I know, it actually isn't.
 
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AlanF

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So imagine this (while cringing). Put the RF 2.0 onto your camera. Then an EF-RF converter, then the EF 1.4 and whatever EF lens on.

Somehow, I doubt that would work.
Your doubts are justified. For a start, the RF-EF converter (which I assume is what you really mean) doesn't fit on to the RF extenders because of their protuberances. You can hack the RF-EF extender by drilling or filing away part of it, virtually down to the bare wiring. Even then, this would increase the distance from the rear of the lens to the extender. For the fun of it, I used the RF-EF extender plus Kenco 3xTC + Canon 2xTC + 400mm f/4 DO II to give a DO 2400mm f/24! Can't say it was worth the effort.
 
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