Patent: Dual internal teleconverter telephoto lens.

Canon Rumors Guy

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Is this the next evolution of the Canon EF 200-400mm f/4L IS USM 1.4x? Here is a patent showing a dual teleconverter Canon telephoto prime, an EF 400mm f/5.6.
What’s cool about the dual teleconverters, is one is a focal length reducer, so you get the EF 400mm f/5.6 and the built-in focal length reducer converter brings the lens to an EF 300mm f/4, or at the other end, a 560mm f/8 lens.
There has long been a desire for a replacement to the classic Canon EF 400mm f/5.6L, even if Canon just added image stabilization, but this is definitely a unique direction to take the lens on Canon’s part.
Japan Patent Application 2019-70689 summary:
Canon EF 400mm f/5.6

Focal length: 391.89mm
F number: 5.80
Angle of view: 3.16°
Image height: 21.64mm
Total lens...

Continue reading...
 
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Would be a funny being! But after taking some time to look at it: A very interesting idea if you look how well the converters work with different lenses - two integrated (in terms of optical design) integrated adapters might be a three-focal-length lens with the excellent IQ of the best primes ... in one package.
 
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AlanF

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This multi-converter lens is cool and all, but I'd much rather see something like a sub-$10k 600mm f/5.6 for us enthusiast mortals who live down here on Earth, and don't want a zoom sigma 150-600 f/6.3
A sub $4k 500mm f/5.6 would be my preferred choice for two reasons. First, weight and secondly wider field of view, and 500mm would help keep the price down.
 
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unfocused

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Not sure I get the point of this lens. Same focal length and aperture as the 100-400 which takes a 1.4 converter very nicely. I suppose a fixed focal length and matched teleconverter might be marginally sharper, but not sure it would be visibly sharper in real world use. Such a lens might be lighter than the zoom, but it would also be longer. Too long to fit in my camera bag. It would make more sense if this were an R lens. Shorter, lighter, maybe faster focus and something different to excite people.
 
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RunAndGun

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Kinda like these that we had in the days of 16x9/4x3 switchable TV cameras. Most of our ENG lenses had a built-in 2x extender, but for a while they added the option of adding in a .7x(I believe) element to maintain the FoV when the camera was switched from 16x9 to 4X3(the sides of the chips were just electronically cropped).

s-l1600.jpg
 
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RunAndGun

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You remember how old TV cameras (1950s?) had three lenses on a rotating mount? Given the RF's short film-to-flange you could probably make something like that that could mount 3 EF lenses.

Leica's rangefinders also had a "Tri-Elmar" lens with three fixed focal lengths. I've used M for decades but literally have never touched the Tri-Elmars. I don't know if they're actually zooms that just have three zoom settings, or whether the image isn't really usabable between the specific focal lengths.

https://www.newsshooter.com/2019/04/10/multi-turret-old-school-meets-new-school/
 
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Ok, just give me 50mm that becomes 70mm and 35mm.

A question to those who understand lens design - would the lens reducer work the same with a 50mm lens?

My limited understanding is it's easy to add a focal length reducer in this case because 400mm / 5.6 is larger than a full frame sensor's diagonal, similar to what's done with speed boosters from FF lenses to crop bodies. My understanding is repeating the trick with a 50mm would require it to have a much larger power of coverage, similar to the TS-E 45mm (though without the mechanics to tilt and shift it, which isn't trivial).
 
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I would have “settled” for a 400/2.8 with 1.4x builtin, as a replacement for my 400 mk II. The 200-400 is too slow for some of the events I cover.

If a reducer could be added, enabling 280(?) f/2, that would be absolutely mind-blowing!

$20k or thereabouts, but worth every penny...
why so expensive ?
The basic 400F5.6 is £1200, adding a couple of inbuilt converters at £450 each would take it to the same price region as the 100-400 Mk 2. This would make a decent birders lens.
 
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