# Patent: Canon RF 120-700mm f/4.5-8 optical formula



## Canon Rumors Guy (Jun 4, 2020)

> Northlight has uncovered a patent showing optical formulas for more super-telephoto zoom lenses for the RF mount. The Canon RF 100-500mm f/4.5-7.1L IS USM will be officially announced soon, but does Canon have plans for an even longer zoom lens for the EOS R system?
> *Canon RF 100-600mm f/4.5-7.1*
> 
> Focal Length: 103mm – 248mm – 600mm
> ...



Continue reading...


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## Doug7131 (Jun 4, 2020)

That would be an awesome lens. Would be up against the 150-600 lenses that Sigma and others make. Although based on how angry some pople got about the 100-500 being f7.1 they may actually explode seeing this is f8.


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## Madtoffel (Jun 4, 2020)

I would love to have a supertelefoto zoom lens for the RF mount that is comparable or better than the Sony 200-600. I hope it comes for less than $2000 and is under 2,5kg.


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## AlanF (Jun 4, 2020)

f/8 at 700mm is very acceptable to me as a compromise between aperture/focal length and size/weight. It should take a 95mm filter and be just under 2kg in weight, and most likely f/5.6 at 400mm. I'd go for this like a shot if the IQ is up to current 100-400mm IQ.


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## Del Paso (Jun 4, 2020)

Provided the IQ is "RF like", this lens will be on my "buy quick" list !


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## pj1974 (Jun 4, 2020)

I'm loving these RF supertele options.... I mean, the 100-500mm was tempting enough... but similar options extended to 600mm and even 700mm.... 

Though obviously not confirmed if the above-mentioned-spec-lenses will ever see the production-light-of-day.... if they do... I would have to seriously consult my normal cash-flow situation and consider cuts to non-essentials like food and toilet-paper in order to buy one of these babies!


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## degos (Jun 4, 2020)

Seems odd to start the zoom range at 120 instead of 200 or even 300. If I'm going long then I generally don't need a short end.

And as for RF mount; it's only Canon's decision that such OEM lenses weren't available on EF, not a technical restriction. Other than AF at f/8, which the later APS-C DSLRs could actually do.


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## Whowe (Jun 4, 2020)

AlanF said:


> f/8 at 700mm is very acceptable to me as a compromise between aperture/focal length and size/weight. It should take a 95mm filter and be just under 2kg in weight, and most likely f/5.6 at 400mm. I'd go for this like a shot if the IQ is up to current 100-400mm IQ.


I don't think it will be f/5.6 at 400mm. The tables seem to indicate f/5.8 at 248mm and 293mm for the 600 and 700, respectively.


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## Whowe (Jun 4, 2020)

f/8 should not be considered a problem. A 1.4x on a 100-400 only gives us 560mm at f/8! The R series does not have the focus limitations of f/8 that previous generations of DSLRs had.

Sigma and Tamron go to 600mm with only a 1/3 stop increase (f/6.3) but they suffer from slower focus and reportedly the IQ is not as sharp as the 100-400 ii. Maybe this slight increase in aperture will be balanced by a reduction in weight!


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## bbasiaga (Jun 4, 2020)

oh man this would be sweet...what do you guys think:

2000-3000$ or 10k+ like the 200-400EF lens? 

-Brian


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## AlanF (Jun 4, 2020)

degos said:


> Seems odd to start the zoom range at 120 instead of 200 or even 300. If I'm going long then I generally don't need a short end.
> 
> And as for RF mount; it's only Canon's decision that such OEM lenses weren't available on EF, not a technical restriction. Other than AF at f/8, which the later APS-C DSLRs could actually do.


If you don't need a short end, then a prime is best.


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## Ozarker (Jun 4, 2020)

bbasiaga said:


> oh man this would be sweet...what do you guys think:
> 
> 2000-3000$ or 10k+ like the 200-400EF lens?
> 
> -Brian


The 200-400mm is a constant aperture lens, which I think is what makes it so expensive. I don't think this lens will be in the $10k range.


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## mpmark (Jun 4, 2020)

we'll after shooting with the original 100-400, the 300 f/4 and then finally the 100-400ii over the last 20 years I finally moved to a 300 2.8ii with 1.4 TC. Although the price is premium I've found myself with the shooting I do to need at least no less then F/4 or lower to get steady shots.

These new lenses will be great in good light for most but I find the light gathering a bit low for my needs. I am really happy with my decision, a 420mm f/4 combo is seriously impressive even compared to my 100-400ii which was a great lens. This combo is sitll hand hold able all day for me atleast. The results makes the cost of switching to it less painful lol.


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## Bert63 (Jun 4, 2020)

Come to me my little naked petunia...


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## magarity (Jun 4, 2020)

Patents that don't get turned into products or licensed to someone else to make into a product are just legal tools to prevent anyone from making that product at all.


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## 6degrees (Jun 4, 2020)

I guess this will be too huge to carry around.


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## flip314 (Jun 4, 2020)

I'm waiting for the Canon 16-1600mm f/8-800


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## PureClassA (Jun 4, 2020)

These small apertures should mate and lower speed be offset nicely with with IBIS! (Provided of course your SUBJECT is pretty stationary)


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## jolyonralph (Jun 4, 2020)

These look likely to have been patented on the path to the development of the RF 100-500 - can't see any chance that either of the lenses on this patent will see it to market so soon after the 100-500.


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## The3o5FlyGuy (Jun 4, 2020)

Hopefully, these will maybe be more "budget Lenses" for the RF super-telephoto line. Because I can def thnk a 200-400 F/4 RF Lens or a new 200-600 RF lens being more of the premium super-telephoto zoom lens


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## IcyBergs (Jun 4, 2020)

This is more about the teles that we haven't seen...still no big white patent or rumors for the RF yet (if memory serves). So...

Conclusions: 

R1 is still a ways away

EF still has a bit of shelf life left before total R takeover


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## usern4cr (Jun 4, 2020)

The patents make it pretty obvious that there is no IS in the lens.  With telephoto focal lengths as long as these lenses have, I probably would wait for other versions that add IS.


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## SV (Jun 4, 2020)

Now that's a cannon!


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## bhf3737 (Jun 4, 2020)

It seems That Canon is confident with AF speed and high ISO performance of the R series cameras and therefore has raised the bar for aperture of affordable long lenses. I shoot usually with EOS R and a Sigma 60-600 and many times together with a 1.4 TC. I can confidently say that AF at f/9 and f/10 is fast and consistent and the result of up to ISO 6400 are acceptable. The R5 and beyond cameras are supposed to be even better with native RF long lenses.


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## mpmark (Jun 4, 2020)

bbasiaga said:


> oh man this would be sweet...what do you guys think:
> 
> 2000-3000$ or 10k+ like the 200-400EF lens?
> 
> -Brian



these patent formulas are not even remotely close to a 200-400F/4 lens, so no they wont be 10k+ price tag like the 200-400F/4


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## Architect1776 (Jun 4, 2020)

Canon Rumors Guy said:


> Continue reading...



Another example of the incredible innovation of Canon and the capability of the RF mount.
This is truly exciting.


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## Architect1776 (Jun 4, 2020)

Doug7131 said:


> That would be an awesome lens. Would be up against the 150-600 lenses that Sigma and others make. Although based on how angry some pople got about the 100-500 being f7.1 they may actually explode seeing this is f8.



That is their mental problem.


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## AlanF (Jun 4, 2020)

6degrees said:


> I guess this will be too huge to carry around.


It could be the same size as a Tamron 150-600mm or a Sigma 150-600mm C with their f/6.3 at the long end, and both are under 2 kg.


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## dwarven (Jun 4, 2020)

usern4cr said:


> The patents make it pretty obvious that there is no IS in the lens.  With telephoto focal lengths as long as these lenses have, I probably would wait for other versions that add IS.



The weight and cost of a lens are also important factors to a lot of people. One of my favorite telephotos is my Sigma 100-400 because I can handhold it all day and it was like $600. Since the R6 and R5 have IBIS maybe they’re trying to cut down on cost/weight.


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## tron (Jun 4, 2020)

Canon Rumors Guy said:


> Continue reading...


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## Daner (Jun 4, 2020)

Do we have the equivalent optical formula for the 100-500? It would be nice to compare it to these to get an idea of the size and likely weight comparisons. But if these are not IS, they must be intended for IBIS-models exclusively, or...?


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## usern4cr (Jun 4, 2020)

dwarven said:


> The weight and cost of a lens are also important factors to a lot of people. One of my favorite telephotos is my Sigma 100-400 because I can handhold it all day and it was like $600. Since the R6 and R5 have IBIS maybe they’re trying to cut down on cost/weight.


I would agree that removing IS would reduce the weight & cost, but I'd be surprised if it was enough weight reduction relative to the heavy weight of the lens to make much of a difference. I would also assume the same regarding cost versus the total cost, since Canon has put IS in so many of their lenses.

I'm guessing that these lenses will be big & heavy enough that most people will just use a tripod or monopod with a R5/R6 with IBIS, and thus the image shake will be much less than if it were handheld. I happen to be a hobbyist who likes to handhold as much as possible, so that's why I'd prefer to wait for an IS version. But if the lens was so remarkable and there was no somewhat comparable IS version available then I would consider it for the times I take a tripod along.


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## Del Paso (Jun 4, 2020)

What if this 120-700 is based on a collapsible design, and ultra compact like the RF 70-200 ???
Anyway, I want it .


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## Marximusprime (Jun 4, 2020)

bhf3737 said:


> It seems That Canon is confident with AF speed and high ISO performance of the R series cameras and therefore has raised the bar for aperture of affordable long lenses. I shoot usually with EOS R and a Sigma 60-600 and many times together with a 1.4 TC. I can confidently say that AF at f/9 and f/10 is fast and consistent and the result of up to ISO 6400 are acceptable. The R5 and beyond cameras are supposed to be even better with native RF long lenses.



While I wait for the R5, I'm renting an R this weekend. I love the 60-600 (it performs extremely well adapted to my Sony A7 III), and I'm looking forward to testing it on the R (along with my 500 and 1.4/2x extenders). I keep forgetting to consider the 1.4 on the Sigma, since I've had the 7D II for so long and factored in its AF issues smaller than f/8.
Do you shoot wildlife with the Sigma? How is it on the R?


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## bhf3737 (Jun 5, 2020)

Marximusprime said:


> While I wait for the R5, I'm renting an R this weekend. I love the 60-600 (it performs extremely well adapted to my Sony A7 III), and I'm looking forward to testing it on the R (along with my 500 and 1.4/2x extenders). I keep forgetting to consider the 1.4 on the Sigma, since I've had the 7D II for so long and factored in its AF issues smaller than f/8.
> Do you shoot wildlife with the Sigma? How is it on the R?


EOS R with Sigma 60-600 work well together. For steady or slow moving birds there is absolutely no problem and AF is consistant and fast. The only thing that can become an issue is EVF that lags behind, so it struggles with fast moving birds but it works well if the focus is locked.


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## Danglin52 (Jun 5, 2020)

Architect1776 said:


> That is their mental problem.



I don't have a problem with f7.1 or f8 EXCEPT you are not going to get the big white backgrounds with these lenses. The lenses will be sharp but will not provide as much separation of an animal from the background. Doesn't mean I won't use them, especially if they are 2-4 lbs lighter than my 200-400.


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## canonnews (Jun 5, 2020)

IcyBergs said:


> This is more about the teles that we haven't seen...still no big white patent or rumors for the RF yet (if memory serves). So...
> 
> Conclusions:
> 
> ...


not so true. we've found RF super telephoto patent applications.

https://www.canonnews.com/canon-patent-applications-another-canon-rf-super-telephoto-application

https://www.canonnews.com/canon-patent-application-more-canon-rf-super-telephoto-primes

https://www.canonnews.com/canon-patent-application-canon-rf-super-telephotos


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## Doug7131 (Jun 5, 2020)

Danglin52 said:


> I don't have a problem with f7.1 or f8 EXCEPT you are not going to get the big white backgrounds with these lenses. The lenses will be sharp but will not provide as much separation of an animal from the background. Doesn't mean I won't use them, especially if they are 2-4 lbs lighter than my 200-400.


That's not really true though. At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul length has a much greater affect on DoF than aperture.


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## Danglin52 (Jun 5, 2020)

Doug7131 said:


> That's not really true though. At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul length has a much greater affect on DoF than aperture.


That is true, but compared through 400mm the f4 should be better and for 560mm @f5.6. There is no comparison above 560mm where the new lens will win without question! Update: it just occurred to me that I can pop on my 2x, not engage the internal TC and have a [email protected] to compare with new lens. It will be interesting to compare the image quality between the two lenses. I think the 700mm might win because the glass is internal versus having a TC in the loop. I have used this setup and the image is actually pretty good.


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## SecureGSM (Jun 5, 2020)

Doug7131 said:


> That's not really true though. At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul length has a much greater affect on DoF than aperture.


Yeah, it’s just 2 stops slower (only??) outdoor lens as in DLO. - DayLight Only


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## privatebydesign (Jun 5, 2020)

Doug7131 said:


> That's not really true though. At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul length has a much greater affect on DoF than aperture.


That simply isn't true. If the subject is framed the same size, which is the whole point of long lenses, the aperture number gives consistent DOF. So a 700mm f8 from further away to give the same subject size on the sensor has greater DOF than a 400mm f4 shot from closer, if you shoot from the same place and crop the 400mm f4 shot to give you the same framing as the 700mm shot you get even less DOF.


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## Mr Majestyk (Jun 5, 2020)

Certainly more useful than the 100-500, but a 250-750 f/5.6-7.1 would be a lot more desirable, similar front element size to 300 f/2.8. Keep it under 3kg and $6K and I would take it over a 600 f/4 these days.

Still not sure why they don't do a 200-600 f/5-6.3, the Sony 200-600 is a superb lens and good value for $2K.


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## privatebydesign (Jun 5, 2020)

Danglin52 said:


> Doug7131 said:
> 
> 
> > That's not really true though. At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul length has a much greater affect on DoF than aperture.
> ...



No, it isn't.


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## Ozarker (Jun 5, 2020)

700mm. I highly doubt I could handhold a 700mm lens and get a sharp shot. I'm not knocking the lens at all. I might actually be interested. I just know my limitations.


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## sulla (Jun 5, 2020)

CanonFanBoy said:


> 700mm. I highly doubt I could handhold a 700mm lens and get a sharp shot. I'm not knocking the lens at all. I might actually be interested. I just know my limitations.


I think you're not really supposed to handhold a 700mm lens.
I once tried it just for fun with a EF 600 (or was it the 800, I don't remember): yes, it works, you can get a sharp image with IS, high ISO plus "point and shoot" technique, but first, it is really difficult to frame the subject carefully and second you can't frame the subject for long due to the weight of the lens.


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## sulla (Jun 5, 2020)

700 @ f/8 is really acceptable for me (way more acceptable than to pay for the 600 f/4 or the 800 f/5.6, which no question will be the better lenses).
Having used f/4 lenses with 2x TC in the past, I can say f/8 is not ideal, but very workable. AF also was OK with the 5D3. I assume (really only assume) that the AF system of R5/R6 will be better yet and will have no issues, at least during dawn to dusk.


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## Billybob (Jun 5, 2020)

sulla said:


> I think you're not really supposed to handhold a 700mm lens.
> I once tried it just for fun with a EF 600 (or was it the 800, I don't remember): yes, it works, you can get a sharp image with IS, high ISO plus "point and shoot" technique, but first, it is really difficult to frame the subject carefully and second you can't frame the subject for long due to the weight of the lens.


An exotic prime is a very different animal from a consumer-grade superzoom, which is what this 120-700 is. I suspect that it will be similar in size to Sony's 200-600 orTamron's 150-600 if not slightly smaller. These lenses are more handholdable than you might think. They do get fatiguing after a while, but I've walked around with them for 2-3 hours at a time getting pictures just as sharp at the end of the shoot as at the beginning. 5.5 lbs seems to be the limit for me. I tried the Sigma 60-600, which is around 6lbs, and that lens was a struggle. Of course, YMMV.


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## Deleted member 381342 (Jun 5, 2020)

I am still hoping for a 200-500 L f/5.6 or 200-600 L f/5.6. Or maybe 400, 500, and 600mm f5.6 primes. The Nikon 500 f/5.6 is incredibly small. They aren’t competing with the f/4 lenses, but that Nikon 500 fits in hand luggage.

OT: if the 120-700 is good and sharp at f/8 it would be a great walk about if you know there is good light. But pointless in some of the places I go, but in the burn my 300 f/2.8 also only manages 1/200 at 6400 ISO


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## Joules (Jun 5, 2020)

privatebydesign said:


> if you shoot from the same place and crop the 400mm f4 shot to give you the same framing as the 700mm shot you get even less DOF.
> 
> View attachment 190715
> View attachment 190716


Not sure how it relates to your point, but in the examples you have there the distance differs in both examples. I think the most relevant comparison is between situations where the subject distance is identical. It still makes sense to me that in that case, only the aperture matters. But could you provide the name (Or link if it is online) of the tool you're using there?


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## AlanF (Jun 5, 2020)

sulla said:


> I think you're not really supposed to handhold a 700mm lens.
> I once tried it just for fun with a EF 600 (or was it the 800, I don't remember): yes, it works, you can get a sharp image with IS, high ISO plus "point and shoot" technique, but first, it is really difficult to frame the subject carefully and second you can't frame the subject for long due to the weight of the lens.


I regularly shoot birds at 500, 560, 600, 700 and 800mm, hand holding with no problems whatsoever to obtain pixel peeping sharpness even with high cropping. And also there has been no problem framing or holding the lens for extended periods even though I am a senior citizen because I use modern lightweight telephoto lenses with good IS at reasonable shutter speeds. I couldn't do that with a 500 or 600mm f/4 but a 700mm f/8 would be an absolute doddle at 2 kg. (I can use easily a 400mm DO II + 2xTC (= 800mm f/8 ) which weighs the best part of 2.9 kg with hood and camo, and most recently a Nikon 500mm PF + 1.4xTC at 700mm feels like a feather, coming in at well under 2 kg)


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## AJ (Jun 5, 2020)

I regularly shoot my Sigma 150-600C at 600/8 handheld with good results. With a monopod or balancing on a fencepost I get a slightly better keeper ratio, but the handheld keepers are just as good as the balanced ones. I think 700/8 won't be a problem, especially with IBIS in the works.


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## Pape (Jun 5, 2020)

Would be nice if they release lense like this with R6 . good beginner kit for wildlife


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## IcyBergs (Jun 5, 2020)

canonnews said:


> not so true. we've found RF super telephoto patent applications.
> 
> https://www.canonnews.com/canon-patent-applications-another-canon-rf-super-telephoto-application
> 
> ...



Fair enough...I didn't recall seeing these before.

All those are about a year old so it's not like the RF tele primes have some hot rumors attached.

So let me ask you this....over/under June 2022 for the R1?


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## privatebydesign (Jun 6, 2020)

Joules said:


> Not sure how it relates to your point, but in the examples you have there the distance differs in both examples. I think the most relevant comparison is between situations where the subject distance is identical. It still makes sense to me that in that case, only the aperture matters. But could you provide the name (Or link if it is online) of the tool you're using there?


The idea is this, most of the time long tele lenses are used to get an acceptable subject size, if the lens is too short (a 400mm) then a longer lens is preferable (a 700mm), but if the 400mm is used either because they didn't have a 700mm etc then people invariably crop the 400mm to get the subject the same size as the 700mm, even if they crop that 700mm they still crop the 400mm even more to get the same framing/subject size.

Now the statement was that _"At f8 700mm, your depth of field will be shallower than a 400mm lens at f4. Focul [sic] length has a much greater affect on DoF than aperture."_ followed by _"That is true" _my point was it isn't true.

So imagine two shooting situations:
1: Two photographers 20 meters from a bird, one has a 700mm f8 the other a 400mm f4 both on the same model camera. The person with the 700mm f8 doesn't need to crop but the person with the 400mm has to crop to get the same subject size. The 700mm f8 has a dof of 0.38m, the 400mm f4 has an initial pre crop dof of 0.59m but after the necessary crop it is approximately 0.35m.
2: Same two photographers, the guy with the 400mm lens is closer to the bird by a factor the same as the focal length difference so when they both take an image the bird is the same size in the image without either cropping. Say the 400mm guy is 10m from the subject, he has 0.12m dof, meanwhile the 700mm guy would be 17.5m away and have a dof of 0.18m

In both real world scenarios the 700mm f8 has greater NOT shallower dof than the 400mm f4.

I just googled a dof calculator and clicked on the first one that came up. https://www.photopills.com/calculators/dof


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## Architect1776 (Jun 6, 2020)

Danglin52 said:


> I don't have a problem with f7.1 or f8 EXCEPT you are not going to get the big white backgrounds with these lenses. The lenses will be sharp but will not provide as much separation of an animal from the background. Doesn't mean I won't use them, especially if they are 2-4 lbs lighter than my 200-400.



Not all of us can afford the 10,000 lenses.
We get superb shots and still can afford a house at the same time.
If we were rich like you then we would all have these 10,000 lenses but that is not the case.


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## Ozarker (Jun 6, 2020)

Architect1776 said:


> Not all of us can afford the 10,000 lenses.
> We get superb shots and still can afford a house at the same time.
> If we were rich like you then we would all have these 10,000 lenses but that is not the case.


I'm thinking of torching the car so I can get one of them.


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## Danglin52 (Jun 6, 2020)

Architect1776 said:


> Not all of us can afford the 10,000 lenses.
> We get superb shots and still can afford a house at the same time.
> If we were rich like you then we would all have these 10,000 lenses but that is not the case.



I was not being critical of less expensive lenses, the conversation was about the aperture and focal length affected DOF. Over the years, I have met many people of modest means that have a passion for a sport or hobby and are willing to allocate resources to that activity. It may be a RV, boat, car, camera gear or other items they value enough to make trade offs - less expensive house/car, etc. I don't think you can assume someone is "rich" simply because they have placed priority on different aspects of their life. For example, I have never been allowed to drive because of my vision so we only need one vehicle. Photography is my only hobby and I don't mind allocating resources to purchase good gear - certainly less expensive than a second vehicle when you consider purchase, insurance, and maintenance. I also know that while great gear helps, it is the photographer behind the camera that is responsible for making the magic. Wildlife photography does push the limits with the need for reach and that is expensive, but there are decent alternatives to see the requirements. As I mentioned on another thread I am buying the 100-500 as a possible replacement for the 200-400, and will sell the 8lb 200-400 if I like what I seen. And finally, if you are smart, you can find some great deals on the Canon refurb or used sites. I paid $7,600 (not $10,000) for a Canon Factory refurb in 2015. The estimate on B&H Used is $5k, so worst case it has cost me $2,600 to own the lens an use it for 5 years. 

Just some thoughts.


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## Fran Decatta (Jun 6, 2020)

If it has a decent Image quality and IS to handheld such tele, would be a serious option to have some fun with extreme focal lenghts. I don't need them, but to get shots of my greyhound running can be great. 

But probably the price will be over 1.200€... even being an f8


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## canonnews (Jun 6, 2020)

IcyBergs said:


> Fair enough...I didn't recall seeing these before.
> 
> All those are about a year old so it's not like the RF tele primes have some hot rumors attached.
> 
> So let me ask you this....over/under June 2022 for the R1?



lenses take years to take from ideas to store shelves. we find (as does NL) patent *APPLICATIONS *they aren't even patents yet. 

2021 for the R1 - I doubt covid-19 will prevent Canon from at least development announcing it and having it available for the games, considering it was leaked that it was coming out last year in 2021 i doubt much has changed.


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## fox40phil (Jun 6, 2020)

Give it to us nowwwww!

But also a nice fixed aperture tele-zoom please! Maybe 5,6 or 6,3f with 200-500 or 300-800 6.3f?! why not ?!


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## privatebydesign (Jun 6, 2020)

Danglin52 said:


> ...the conversation was about the aperture and focal length affected DOF.


Which was categorically wrong.


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## Del Paso (Jun 7, 2020)

CanonFanBoy said:


> 700mm. I highly doubt I could handhold a 700mm lens and get a sharp shot. I'm not knocking the lens at all. I might actually be interested. I just know my limitations.


Forget about your "limitations".
Optical stabilization plus IBIS are all you need. Depending on the speculations, they could allow a gain of up to 6-8 speeds.
So, no excuse to refrain from buying one...


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