# Patent: Canon RF 70-300mm f/4-5.6 IS



## Canon Rumors Guy (Feb 21, 2019)

> Another detailed patent for an RF 70-300mm f/4-5.6 IS lens has appeared, the first one came as part of a patent for an RF 100-400mm f/3.5-5.6L IS USM.
> The 70-300mm zoom lens has always been a part of the budget telephoto zoom lens lines of various manufacturers, and it makes sense that we’ll see one for the RF mount, and likely sooner than later.
> *Japan Patent Application 2019028212*
> 
> ...



Continue reading...


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## Sharlin (Feb 21, 2019)

Huh, interesting construction. The BF actually decreases when you zoom in. Also seems Canon engineers are happily taking advantage of the short BF distance even with telephoto designs.


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## GMCPhotographics (Feb 21, 2019)

It looks quite short at the 70mm end and erm...quite long at the longer end. I guess that's the compromise for the external zoom and "design it as small and neat as possible at the short end" design philosophy.


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## motofotog (Feb 21, 2019)

I was hoping there might be a patent for RF150-600 or 200-600 lens.


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## dolina (Feb 21, 2019)

Just one 70-300, please. Canon at one time had more more than three 75-300 & three 70-300 available at a given time. Consolidating them all into one SKU would allow for cheaper lenses through economies of scale.


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## flip314 (Feb 21, 2019)

dolina said:


> Just one 70-300, please. Canon at one time had more more than three 75-300 & three 70-300 available at a given time. Consolidating them all into one SKU would allow for cheaper lenses through economies of scale.



I think it's likely.

The current EF 75-300 is a horrible lens, but it's cheap and already designed. These days there are far better options, 55-250 for crop and 70-300 for FF.

The EF 70-300 IS II USM is an amazing lens at a reasonable price. The EF 70-300L is a bit of an oddball, and these days I don't think it makes sense compared to the amazing 100-400L II.


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## dolina (Feb 22, 2019)

flip314 said:


> The EF 70-300L is a bit of an oddball, and these days I don't think it makes sense compared to the amazing 100-400L II.


Price, physical size and weight may be a factor.

Again just one RF 70-300mm.


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## pj1974 (Feb 22, 2019)

dolina said:


> Price, physical size and weight may be a factor.
> 
> Again just one RF 70-300mm.



The size, weight and zoom range of the 70-300mm L works very well for me (on my 80D and 7D).
I bought it soon after it was available, and I love that lens. My copy has great optics.

Being so portable makes it such a great lens for a variety of purposes. A similar RF model would serve me well when I move to mirrorless.


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## blackcoffee17 (Feb 22, 2019)

flip314 said:


> I think it's likely.
> 
> The current EF 75-300 is a horrible lens, but it's cheap and already designed. These days there are far better options, 55-250 for crop and 70-300 for FF.
> 
> The EF 70-300 IS II USM is an amazing lens at a reasonable price. The EF 70-300L is a bit of an oddball, and these days I don't think it makes sense compared to the amazing 100-400L II.



If you don't need the 300-400mm focal lengths, the 70-300 is so much smaller and lighter. Even worth getting both and only take the heavier 100-400 when you really need it


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## Maximilian (Feb 22, 2019)

Sharlin said:


> Huh, interesting construction. The BF actually decreases when you zoom in. ...


Indeed! I wasn't expecting something like that. But I am no lens designer 

So with the RF compared to the EF 70-300 IS II USM (+44mm EF flange) you'd get the following length:

At 70 mm:
RF: 179.52mm
EF: 189,5 mm
At 300 mm:
RF: 250.81mm
EF: ~ 262 mm (measured from picture as I have no exact values available)
So on both ends the new lens is about 1 cm smaller than the EF pendant.



dolina said:


> Just one 70-300, please. ...


I could live with two of them: one "*non-L*" and one "*L*".
First one comparable to the EF 70-300 IS II USM, maybe with STM if that works well.
Second one with better mechanical built, sealings, USM, more complex optical formula and therefore better IQ.
So everybody could get what they can afford.
Otherwise agreed.


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## Flamingtree (Feb 23, 2019)

I


blackcoffee17 said:


> If you don't need the 300-400mm focal lengths, the 70-300 is so much smaller and lighter. Even worth getting both and only take the heavier 100-400 when you really need it



I agree. The 70-300L is great for taking on a trip etc. then something (not obscenely) expensive that gives you 400 to 600 for wildlife would be kind of cool.


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