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Canon will bring an RF 400mm f/4 DO IS USM to the lineup in 2024

I am exited to see what has happened in 10 years development of DO/Fresnel lenses.
Nikon showed some things that made some of us on the Canon site jealous, indeed.
New materials and new production methods should become visible in IQ.
 
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I am exited to see what has happened in 10 years development of DO/Fresnel lenses.
Nikon showed some things that made some of us on the Canon site jealous, indeed.
New materials and new production methods should become visible in IQ.
I have had two copies of the Canon 400mm f/4 DO II, and my Nikon 500mm f/5.6 did not have better IQ. But, the Nikon was much lighter and about half the price here. The DO/PF lenses all suffer performance against bright backgrounds because of the zero-order spectrum of the diffraction grating. But, you need the light behind you anyway. My RF100-500mm at 500mm outperformed the DO at 400mm, and a 400/4 has only 1 stop more photons/duck than a 400/5.6 or 500/7.1. With a 2x TC at 800/8 it will be only 1/3rd stop faster than the 200-800 at 800mm f/9. Let's see how good it is and the price and the price and weight.
 
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Interesting. I wonder if the direct replacement White primes will all be DO lenses going forwards. It makes sense if this lens is built as a RF 400mm f2.8 DO and then releasing a 100-400mm f2.8 L. It literally could be a smallest adn lightest 400mm f2.8 ever constructed.
If all big whites became DO, why would they bother putting it in the name? (The RF f/11 supertele primes have DO but it's not in their designation).

The rumour is for an f/4, not f/2.8.
 
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If all big whites became DO, why would they bother putting it in the name? (The RF f/11 supertele primes have DO but it's not in their designation).

The rumour is for an f/4, not f/2.8.
There is a patent for a 400mm f2.8 DO and a 600mm f4 DO. The 600 f4 DO was seen as a singular prototype at a show a few years back.
Just because Canon have alrfeady made two EF 400mm f4 DO's....there is nothing to stop them developing a RF 400mm f2.8 DO.
 
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There is a patent for a 400mm f2.8 DO and a 600mm f4 DO. The 600 f4 DO was seen as a singular prototype at a show a few years back.
Just because Canon have alrfeady made two EF 400mm f4 DO's....there is nothing to stop them developing a RF 400mm f2.8 DO.
Of course, and it could be a good way to differentiate a mark II RF 400 2.8. But I guess that's a fair way off.
 
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I have had two copies of the Canon 400mm f/4 DO II, and my Nikon 500mm f/5.6 did not have better IQ. But, the Nikon was much lighter and about half the price here. The DO/PF lenses all suffer performance against bright backgrounds because of the zero-order spectrum of the diffraction grating. But, you need the light behind you anyway. My RF100-500mm at 500mm outperformed the DO at 400mm, and a 400/4 has only 1 stop more photons/duck than a 400/5.6 or 500/7.1. With a 2x TC at 800/8 it will be only 1/3rd stop faster than the 200-800 at 800mm f/9. Let's see how good it is and the price and the price and weight.

These are the comparisons I was thinking about. The 200-800 at $1900 is going to be tough to beat for those of us who imagine using a 400+tc. I think the value proposition might only make sense for those who want to shoot at 400mm. This gets you there at a light weight sacrificing one stop of light vs the 400 f/2.8 (a $12k lens) at a lower cost. But the EF 400 DO is still $6,900! I just don't see how the RF version can support even that level. When the EF version came out, effective 600mm at f/8 was the sweet spot achievable with pretty good glass in the $2k range. The 400 f/4 with extenders would get you 560 at f/5.6 or 800 at f/8., thus giving it a reason to exist beyond 400 prime shooting. The new RF 800 at f/9 for under $2k kills that.

All of that is to say, EF price suggest $8k would reasonable, but I don't see why anyone would buy it at that price. You are down to 400 prime shooters who are pros, I don't think they are going to give up the subject separation to save $4k. But I'm not a pro, so I'll leave it there.
 
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These are the comparisons I was thinking about.
A stop of light always costs a lot of money. The 70-200/2.8L is almost twice the cost of the 70-200/4L. The 24-105/2.8L is almost three times the cost of the 24-105/4L.

If Canon brings an RF 400/4 DO to market, it will be because they believe it will be profitable, and it will be priced accordingly.
 
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These are the comparisons I was thinking about. The 200-800 at $1900 is going to be tough to beat for those of us who imagine using a 400+tc. I think the value proposition might only make sense for those who want to shoot at 400mm. This gets you there at a light weight sacrificing one stop of light vs the 400 f/2.8 (a $12k lens) at a lower cost. But the EF 400 DO is still $6,900! I just don't see how the RF version can support even that level. When the EF version came out, effective 600mm at f/8 was the sweet spot achievable with pretty good glass in the $2k range. The 400 f/4 with extenders would get you 560 at f/5.6 or 800 at f/8., thus giving it a reason to exist beyond 400 prime shooting. The new RF 800 at f/9 for under $2k kills that.

All of that is to say, EF price suggest $8k would reasonable, but I don't see why anyone would buy it at that price. You are down to 400 prime shooters who are pros, I don't think they are going to give up the subject separation to save $4k. But I'm not a pro, so I'll leave it there.
More about my 2 EF 400mm DO IIs. The first I used very happily for several years as great for BIF at 400/560mm and for perched at 800mm. I sold it when I went over to the 500/5.6 PF, but then bought a second used copy cheap when I went to the R5. But, I never used it when I got the 100-500 and sold it at a profit. No way I'd buy another if it is up in the high thousands. (Do you mean there will be only 400 shooters;)?)
 
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I would like to see Canon take DO, BR, and whatever other tech acronym they've got and use it to make a 400 f2.8 that weighs in at 2kg or less. That would be a big win.

As for Rf 400 f4 DO it should weigh less than Sony's new 300 f2.8, preferably 1.2kg or less.
 
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