New rumor of Supertelephoto DO’s and the R1 [CR2]
- Thread starter Richard CR
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Many could focus at f/8 though, including the APSCs such as the 80D and 90D, and with their crop factor considered, these are really operating at f/12.8 at the full-frame equivalent f/8 aperture. I'm sure Canon would have been able to build a 500mm f/7 apsc only lens, which would have been the same optically, and possibly smaller, considering the fairly compact size of the Sigma 100-400mm, which is a zoom with aperture blades.
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davidcl0nel
Canon R5, 17 TSE, RF35+85 IS, RF70-200 4 IS, EF135
Only on _one_ AF point in the center. On an 800mm it would be not such a problem (but its even f/11), but Canon also build zooms with f/8 on the long end (like the 100-400), which they would never do for EF. On 400mm I want also not-centered AF points, to use rule of thirds or focus on the eye/head of somebody/thing.
And so these lenses can be smaller, because on EF Canon always uses maximum of f/5.6....
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Your logic fails you. In general neewly designed RF lenses have been clearly better than their EF-equivilants mechanically and optically. The 50mm prime is probably the best example. I have full confidence that the new materials will hold just as well or better than the old. Lens Rentals tear down shows impressive Canon engineering, excellent solutions and upgraded mechanics - also belying your sweeping claims that Canon is taking more but giving us less.Manufacturers are competeing with each other in a shrinking market and looking for ways to give consumers a few more features to compel them to upgrade while still making a sufficient profit. Some of the lenses they produce on the new RF platform my hit the right balance of image quality, value for money, innovation (new features) and profitability, while others wont, and time will tell which falls into each respective category.
Lensrentals verdict on the RF 70-200mm f/2.8:
"a LOT of engineering progress has been made. The Canon RF 70-200mm f/2.8 is a complex beast, but you get a quick feel for it being organized complexity, and it’s actually a much simpler layout than those other lenses. Some of that is from the improved optical design; there’s less glass floating around. Some of it is the use of linear focusing motors.
Most of it is superior electro-mechanical engineering and a brand-new, ground-up design. It’s clear those other lenses were improvements on existing designs. Over the years, as various versions of the lenses have been released, it’s apparent that they started with the previous design and modified it. Like a lens paleontologist, we could see the bones of the original beast with layers of new complexity and modifications added in the newer version. (Yes, I’m very aware it was Sony’s first FE 70-200mm lens, but, to be polite, it heavily borrowed from other 70-200mm lenses mechanically).
This lens was a new design from the ground up. There’s no ‘that’s the way we’ve always done it’ holdovers. That’s a lot more work for the designers, but the result is a beautifully engineered, fully modern lens. It’s clean, functional, and straightforward.
It’s obviously very robustly engineered from a mechanical standpoint. The internal composites are strong as hell. There are double cams, rods, and posts everywhere. There’s no play in any moving parts. We can’t imagine there will ever be play in the moving parts unless you run over it with a truck. You could describe it as ruggedized, but I’m going to stick with Strong, Like Bull, and suggest we refer to this as the RF-SLB 70-200mm f/2.8 from now on.
There are a lot of nice touches, like the air filter tape over the openings around the front group. Will it prevent the lens from getting dust inside? Of course not; every lens gets dust inside. But it’s helpful and shows they’re trying. It’s also the first lens in a decade that I can say was obviously designed with ease of repairability in mind, at least as far as they could."
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On the Canon 7D II perhaps, but 27 AF points on 80D and 90D at f/8.
I've had an 80D for quite a while, awesome camera!
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From the Canon site, "What's new: EOS 80D - AF at f/8 max. apertures"
Lenses providing this broader 27-point coverage at f/8 effective maximum apertures with the EOS 80D are:
EF 100–400mm f/4.5–5.6L IS II + Extender EF 1.4x III
EF 200–400mm f/4L IS Extender 1.4x lens + Extender EF 2x III (built-in extender not used)
Summary
Focus with 27 AF points, at f/8, with newest tele lenses + extenders
For years, photographers have grown used to assuming that if they wanted additional features like the ability to use autofocus with lenses slower than f/5.6, that they needed to turn to advanced, high-end digital SLR cameras. Canon engineers have begun to listen to the growing requests from our customers who want the ability to continue to use AF, without requiring big, heavy and expensive super-telephotos with wide apertures to achieve this if they want to add a tele extender.
The EOS 80D’s new 45-point AF system is a strong testament to this. It provides AF at the center AF point with almost all combinations of compatible Canon EF telephoto lenses and Canon-brand tele extenders with f/8 (effective) maximum apertures. And, it expands this to an outstanding 27 available AF points at f/8, with the two new lenses mentioned immediately above, if combined with the latest Version III tele extenders. Even if you’re using an older lens or extender, though, the EOS 80D will make it possible to get more out of your gear, and at a much lower cost of entry, than the higher-end cameras that would have been required previously.
(source: https://www.usa.canon.com/internet/...tures/Whats-New-EOS-80D-AF-at-f8-max-apetures)
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From DP review:
The Canon 90D, when using apertures of F8 and wider, there are 27 points, nine of which are cross-type.
(source: https://www.dpreview.com/reviews/canon-eos-90d-review/2)
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The apparent narrower aperture with a crop sensor applied only to DoF when you move further from the subject to match framing. In the context of AF, it’s a red herring.
Also, for telephoto lens designs the diameter of the image circle is not limiting. A 500/7 APS-C lens would be no smaller than a 500/7 FF lens.
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"Your logic fails you."
I hope not!Don't get me wrong, I like a lot of the new RF lenses, have a few of them already, most are a bit better than their EF equivalents where they exist, but they're usually a lot more expensive relative to how much of an improvement they are, compared to their older counterparts.
If, by 50mm prime, you mean the nifty fifty, I have both, and prefer the slightly better but they're charging much more for RF 50mm f/1.8 ($200 vs $125 for the EF, or 60% more). If you're talking about the 50mm 1.2 L, then we're in exorbitant price territory, but they're improved that lens a lot, much sharper, if you value sharpness. But the EF 50mm f/1.2L USM sells for $1349, vs the $2299 price tag of the RF 50mm f/1.2L USM, that's a huge price hike!
The solid metal big whites have been proven out in the field, those things have been used in warzones and have survived the worst of treatment under the most shocking conditions. In engineering, all things are compromises, and you can't get rid of a solid armored one piece sealed metal shell that weights a heap, replace it with a lightweight telescoping plastic zooming mechanism, and expect the same durability. That's absurd, the fact that you have a sliding, extended piece is a glaring sign that you have a potential point of breakage. How much lateral force duou you imagine that could stand if you swung around and hit it, or it fell at an angle. Where would the force go? The light weight and compact size is chosen over durability in the RF version of the 70-200mm f/2.8. EF 70-200mm f/2.8L IS III USM (Canon Store: $2099.00) vs RF 70-200mm F2.8 L IS USM Canon Store: $2799.00), a 40% price increase, really?
I don't do the brand loyalty thing, each lens has to stand on its merit. Like the EF range, some RF lenses will be awesome, some average, some mediocre, and some, well... You get the picture. What is guaranteed is that you'll be paying much more for any modest improvements, let alone major ones.
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Hi Neuro, I don't get your first point, you might need to explain further. I'm talking pixels on bird at same distance, not everyone has an R5 lol, of all the RF camera bodies the next highest MP models are the EOS R and RP respectively if I'm not mistaken.
Precisely, a 500mm f/7 APS-C lens would be no smaller than a 500mm f/7 FF lens, but most likely smaller than an 800mm F/11 extended for use.
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You replied to the point by @AEWest that, “The rf 800 f11 could not be made in ef mount because the focusing wouldn't work in DSLR at f11,” with a statement that, “Many could focus at f/8 though, including the APSCs such as the 80D and 90D, and with their crop factor considered, these are really operating at f/12.8 at the full-frame equivalent f/8 aperture.”
I inferred that to mean you were suggesting an f/11 lens could AF on an APS-C DSLR. Probably I misunderstood your intent.
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Suggest you study the trade off between weight, rigidity, force and impact. A lighter lens with a less rigid shell will suffer a lot less force to the critical fragile inner parts than the glass within a heavier, stiffer metal counterpart. Take a look at your car and just consider how - extremely - much better that car manages to reduce total impact with its "soft" composite shell than the steel coffins people were driving yesterday. As for extended pieces - another illogical argument. I could also ask which lens do you think will suffer the largest force: the pulled back RF or the long EF-model when hit at an angle? I trust you know the answer."Your logic fails you."
In engineering, all things are compromises, and you can't get rid of a solid armored one piece sealed metal shell that weights a heap, replace it with a lightweight telescoping plastic zooming mechanism, and expect the same durability. That's absurd, the fact that you have a sliding, extended piece is a glaring sign that you have a potential point of breakage. How much lateral force duou you imagine that could stand if you swung around and hit it, or it fell at an angle. Where would the force go?
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The car analogy is not a good one. The reason the modern car is safer is because there is a rigid passenger cage with a crumple zone in front that deforms to absorb the impact and lower the deceleration forces. If you put a crumple section in front of the old steel “coffin” it would function as well (and safety bags etc importantly help). A disposable lens hood in the front of a metal lens would act as a crumple zone for a head first fall. The internal components within a lens would be protected by impact protection structures like rubber between them and the rigid frame, like we know the RF 100-500mm has for its IS unit that does not park like in the EF lenses.
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Hmmm, not really sure that's the case. It's basic engineering/physics, were talking a two-piece unsupported structure vs a solid structure.
Exert a force perpendicular to the lens body, over its centre. In the solid structure the stresses will be exerted over the lower surface, taken up by the material, which will not deform in the case of a metal lens body unless it leads to destructive failure, much like a load bearing beam spanning two points.
With a structure that consists of a weaker material formed as a tube within a tube, the stresses will all be placed on the area of the joint. The bottom edge of the inner tube will cut into the inner surface of the outer tube, and act like a lever. Of course we're talking about an extended lens, which you've steered away from discussing
This is not a point that can validly be argued from an engineering perspective. Without getting into force vector diagrams, ask yourself why bridges are constructed of solid beams and not loose tubes sliding inside each other. Or just extend the RF 70-200mm lens and sit on it!
Is it so hard to imagine that a company would trade strength and durability for weight and size in a product? It's done all the time with all manner of things.
The simple rule with engineering is that when you add to something, you take away from something else - because there is no such thing as a free lunch! The imaginary perfect material or structure that is the best at everything and fits every need is nonexistent by definition.
Probably best to be aware of the potential weaknesses of a new design and treat the gear with respect to ensure it doesn't get damaged, rather than assume it's better in every way because it's newer, that would be a logical fallacy.
Practical advice, don't treat an extended telescoping lens made of engineering plastics as it it were a solid, single-piece alloy traditional big white, that would be a sure way to wreck a really good expensive lens.
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The real correction isnt for distorted optics, it was for low light levels, looking through an optical VF has its own issues.
F8 was noticeably darker, let alone the F11 or F16 as you can now do with the 800F11+TC. I got to take a picture of a bird at 125th at 800mm, 6400 ISO - through an optical VF I suspect I wouldnt have been able to see the branch, let alone the bird.
F8 was noticeably darker, let alone the F11 or F16 as you can now do with the 800F11+TC. I got to take a picture of a bird at 125th at 800mm, 6400 ISO - through an optical VF I suspect I wouldnt have been able to see the branch, let alone the bird.
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Um, how do I say this gently...
The optical distortion of the RF 16mm f/2.8 and RF 14-35 f/4 is absolutely shocking, you're talking about two totally different issues here. Vignetting is also bad, around 2-3 stops I believe, on all RF lenses, much worse than EF mount. Its a flaw of the RF mount design because 'physics and engineering', you can't get something for nothing...
The discussion was whether shooting at f/11 was a mirrorless camera design miracle or no big deal, something that could be done on a DSLR.
There's nothing like straight evidence, here's a video by bird photographer Duade Paton, who does this very test using a Canon 5D IV DSLR and a 500 f/4 turned into a 700 f/11. It can be done! He does it to prove that the RF f/11 lenses are usable at those settings. He also has other videos where he tests the actual lenses.
Unless you're shooting at dawn or dusk or other low light conditions, shooting at f/11 is no big deal in terms of available light. Most macro photographers shoot at that aperture (and manually focus because all AF has its limits when DOF is measured in millimetres) and I believe many landscape photographers do too. Incidentally a lot of macro is shot on APSC, so their f/11 is actually equivalent to f/17.6 on FF.
For perspective, yes, it's exciting to have all those extra focus points on a mirrorless camera, and to be able to use a lot of them with the AF, but once again, there's no such thing as a free lunch when it comes to engineering. Anyone who has done any amount of photography using a mirrorless camera has had the experience where once the camera locks onto something in the background, and the foreground subjects are blurred out of focus, the camera refuses to lock back onto them, because it can't see them, and can't lock focus on what it can't see on the sensor, as that's how focussing works on these camera bodies.
Most of us either put our hand in front of the lens, point the camera to a large nearby object, or towards the ground and half-press the shutter butter to re-acquire focus. DSLRs have a separate autofocus system so they don't have this problem, but sometimes this system goes out of alignment with the lens/sensor and microadjustments are needed to get maximum sharpness from the lens. Like I said, different approaches to an engineering problem yield different benefit, but also different shortcomings, that's the way the physical world works, for better of for worse!
Here's a video of the problem here, by the same photographer.
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I guess we're in agreement then, great!
Not really, but you misunderstood my point, it was about how easy it is to actually _look through_ an optical VF when the aperture is actually set to F11 or F16 at a small target with a long distance lens in lower light.
It makes the VF quite dim and lower in contrast, which can be corrected by mirrorless, and in my view is rather valuable.
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Especially on a lens like the MP-E 65mm, where it behaves like f/16 when used wide open at 5x magnification. This is why the original eos M was such a good fit for that lens, for me.
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Well, I already knew that, and I like that benefit of my mirrorless camera too, so it's all cool!
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