Patent: Canon 70-200mm f/2.8 DO

[Fleetie]

Do we have a patent for the 70-200/f2.8 IS USM II to compare it with?

Because otherwise, this patent is for a lens that is longer (223mm) than the 70-200/f.8 IS II USM (199mm) although nothing is said of diameter/weight.

So "DO" = "smaller" does not seem to apply here.

Sorry, but wrong, dilbert!

Because the 223 mm is the optical formula from front element to image plane. You have to subtract the flange distance (40 + x mm).

Physical length of the lens (if EF mount) would be 223 mm - 40 mm = 183 mm (or even less)
So this makes the lens about 2 cm shorter.

That a new interpretation of what's included in the patent (nobody has said this before) and goes against the how everyone else reads it. Care to explain?

Yes, they have said it before. I read someone saying you have to subtract the 44mm flange distance only last week on here.

 

[Maximilian]

Do we have a patent for the 70-200/f2.8 IS USM II to compare it with?

Because otherwise, this patent is for a lens that is longer (223mm) than the 70-200/f.8 IS II USM (199mm) although nothing is said of diameter/weight.

So "DO" = "smaller" does not seem to apply here.

Sorry, but wrong, dilbert!

Because the 223 mm is the optical formula from front element to image plane. You have to subtract the flange distance (40 + x mm).

Physical length of the lens (if EF mount) would be 223 mm - 40 mm = 183 mm (or even less)
So this makes the lens about 2 cm shorter.

That a new interpretation of what's included in the patent (nobody has said this before) and goes against the how everyone else reads it. Care to explain?

Sorry again, wrong again!

You did a common failure, that I did before, too.
Just browse through the latest patent threads here.
Edit: or search for "flange" in the forum search. You'll find dozens of examples here.
So please don't use phrases as highlighted above. Thank you.


I won't post any links, for work you should have done yourself.

 

[moreorless]

If its a high end video lens it could well be I spose that the DO saves more space than that as it would otherwise have been a lot larger but looking at the 70-300mm DO it does seem that the size saving with these kinds of zooms is a bit more limiting.

What I think Canon do need to respond to is Nikons 300mm F/4 PF, that's opening up a potentially new market for wildlife shooting on something like the D500 for people who wouldn't otherwise bother with that range due to the size/weight involved.

 

[Loswr]

Do we have a patent for the 70-200/f2.8 IS USM II to compare it with?

Because otherwise, this patent is for a lens that is longer (223mm) than the 70-200/f.8 IS II USM (199mm) although nothing is said of diameter/weight.

So "DO" = "smaller" does not seem to apply here.

Sorry, but wrong, dilbert!

Because the 223 mm is the optical formula from front element to image plane. You have to subtract the flange distance (40 + x mm).

Physical length of the lens (if EF mount) would be 223 mm - 40 mm = 183 mm (or even less)
So this makes the lens about 2 cm shorter.

That a new interpretation of what's included in the patent (nobody has said this before) and goes against the how everyone else reads it. Care to explain?

It's only a new interpretation of poor reading comprehension that goes against your typical misunderstanding of facts.

http://www.canonrumors.com/forum/index.php?topic=30018.msg601035#msg601035
http://www.canonrumors.com/forum/index.php?topic=29603.msg590954#msg590954
http://www.canonrumors.com/forum/index.php?topic=30090.msg603167#msg603167
http://www.canonrumors.com/forum/index.php?topic=28676.msg566117#msg566117
http://www.canonrumors.com/forum/index.php?topic=26834.msg530239#msg530239

...and many, many other examples.

Seriously, before you question someone else's statement of fact and claim you and 'everyone else' disagree, try actually doing a little research and fact-checking first. At the very least, avoid claiming that your understanding or knowledge (= lack thereof) is shared by anyone else, let alone 'everyone else'. It might help you avoid looking foolish, if you manage to do it consistently. You might even learn something.

 

[3kramd5]

I also see no optical reasons to change anything for a video lens.

The biggest difference between most still zooms and video zooms are that video zooms are parfocal, and still lenses are not.

+1

 

[Maximilian]

I also see no optical reasons to change anything for a video lens.

The biggest difference between most still zooms and video zooms are that video zooms are parfocal, and still lenses are not.

Thank you for reminding me of that.
"parfocal" is something I forget about quite often.

 

[Maximilian]

...

...
Physical length of the lens (if EF mount) would be 223 mm - 40 44 mm = 183 179 mm (or even less) (edit: corrected my own math here)
So this makes the lens about 2 cm shorter.

Well I've never read any posts on here (prior to this) mentioning this.

Nevermind! As I said, I had to learn that, too.
And despite the fun of rumors there is always something to learn here

 

[K-amps]

They need to do an 70-200mm F/2.0 IS with DO. I'd be happy to pay twice what they are asking for the F/2.8ii IS version if it is as sharp. Canon should not care if it eats into the sales of the 200 F2 if they can more than make up on volume sales of the zoom.

And the 70-200 f/2 IS DO would be less expensive than the 5k prime because... ?

Nikon offers a 500 f/5.6 zoom for about $1750. That's a front element equivalent of 250mm F/2.8 or roughly a 90mm aperture and associated Element size. A 200mm F/2 would be a 100mm aperture etc. I am being quite generous, in willing to pay Canon $4000 for en extra 10mm in size increase. You can come up with any scaling you desire for this... I stated what I am willing to pay for it given the possibility of competitors offering such products that are quite comparable from a manufacturing cost perspective.

If this challenges your perception of what value you deserve, then understand that Nikon offers what is an equivalent of 200mm F/2.2 for $1750.

They need to do an 70-200mm F/2.0 IS with DO. I'd be happy to pay twice what they are asking for the F/2.8ii IS version if it is as sharp. Canon should not care if it eats into the sales of the 200 F2 if they can more than make up on volume sales of the zoom.

You spelled "eight times" wrong.

;D

They need to do an 70-200mm F/2.0 IS with DO. I'd be happy to pay twice what they are asking for the F/2.8ii IS version if it is as sharp. Canon should not care if it eats into the sales of the 200 F2 if they can more than make up on volume sales of the zoom.

Even if the lens is twice as heavy?

Yes. If its DO, there will be some weight savings, even if not, then its still ok, the Prime 200mm F/2.0 is what it is and most loved despite its weight. If someone wants a lighter version, Canon will be happy to sell them an F/4 or F/2.8 variant.

 

[Random Orbits]

They need to do an 70-200mm F/2.0 IS with DO. I'd be happy to pay twice what they are asking for the F/2.8ii IS version if it is as sharp. Canon should not care if it eats into the sales of the 200 F2 if they can more than make up on volume sales of the zoom.

And the 70-200 f/2 IS DO would be less expensive than the 5k prime because... ?

Nikon offers a 500 f/5.6 zoom for about $1750. That's a front element equivalent of 250mm F/2.8 or roughly a 90mm aperture and associated Element size. A 200mm F/2 would be a 100mm aperture etc. I am being quite generous, in willing to pay Canon $4000 for en extra 10mm in size increase. You can come up with any scaling you desire for this... I stated what I am willing to pay for it given the possibility of competitors offering such products that are quite comparable from a manufacturing cost perspective.

If this challenges your perception of what value you deserve, then understand that Nikon offers what is an equivalent of 200mm F/2.2 for $1750.

The front element size does not provide perfect correlation for what a lens costs, so scaling that way is not perfect. Specific technologies and materials (fluorite and DO) cost more even if the max aperture size remains constant. Marketing sets the price to maximize profit, not to provide users the most value/lowest price, so the question really is this: how often does a zoom that has a max aperture as large as a prime cost less than the prime? 70-200 II costs more than the 200 2.8 II, 24-70 f/2.8 II (no IS) costs more than 24 IS, 28 IS. 100-400 II costs more than 400 f/5.6. A lens that costs 4000 is L-lens territory, and do you really think that a zoom that goes to 200 f/2 with IS will be less expensive than the prime, which is 5k+?

By your same logic, Nikon's price for its 200 f/2 should also be closer to 2k, but it is also 5k+ like the Canon. Canon's 200-400 costs significantly more than Nikon's 200-400 + 1.4x which by your logic should be similar in price. Don't get me wrong, I'd love to see a 70-200 f/2 for 4k and I'd buy one too. I just don't think that it'd be 2x the 70-200, which according to CPW streets for 1700 or even 4K. It'd be higher than the f/2 prime.

 

[j-nord]

Is there any evidence that Canon is serious about a DO zoom? The 70-300 DO was awful and their only attempt so far. I bet they are just doing research into the plausibility of a DO zoom rather than having plans to actually produce one anytime soon.

 

[Maximilian]

Is there any evidence that Canon is serious about a DO zoom?
...

Who knows?

Right now I suppose that they're just about to stake their DO claim.
The 400 DO II is labeled as brilliant lens, and definitely much better than it's predecessor, see here
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=338&Camera=453&Sample=0&FLI=0&API=0&LensComp=962&CameraComp=0&FLIComp=0&APIComp=0
and here
http://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f-4.0-DO-IS-II-USM-Lens.aspx

So this shows that they've improved their tech.
And why shouldn't that trickle down to more mainstream lenses as well?
It's a question of time (and price). And until then patents protect their knowledge.

 

[Maximilian]

Indeed, live and learn

If I go back and look at the patent, the patent mentions the length as being "L0" (L-zero) and in the diagrams this always includes the length back to the IP (Image Plane.)

Also, the length (L0) refers to the length from the front of the first element to the image plane. So there's probably 5mm or so extra on most lenses for the filter thread bit however for a lens such as the 300/f4, the actual lens might even match the patent length due to the heavily recessed front element.

100% correct. This is something I didn't put into my calculation because these 2 - 5 mm for filter thread and front element cell didn't bother me.

 

[Luds34]

I also see no optical reasons to change anything for a video lens.

The biggest difference between most still zooms and video zooms are that video zooms are parfocal, and still lenses are not. The non-IS 70-200/2.8L version is parfocal.

Although I've heard reports of people who have a varifocal copy, I suspect either these copies are not in spec or there are multiple editions of the lens. I still own the one I bought in 1998, it's parfocal, and that is part of the reason it's been in my arsenal such a long time.

Is that true? That the 70-200 f/2.8 IS II is not parfocal? I guess I just sort of took for granted that a number of the higher end lenses were parfocal. I do own the f/2.8 non-IS. I also believe my other zooms are parfocal.

I mostly shoot primes but I should keep this in mind for when I shoot zooms. I'd hate to be focusing, then at the last second tweaking the zoom a bit for better composition, not realizing I'm adding a slight softness to the shot.

 

[Loswr]

I also see no optical reasons to change anything for a video lens.

The biggest difference between most still zooms and video zooms are that video zooms are parfocal, and still lenses are not. The non-IS 70-200/2.8L version is parfocal.

Although I've heard reports of people who have a varifocal copy, I suspect either these copies are not in spec or there are multiple editions of the lens. I still own the one I bought in 1998, it's parfocal, and that is part of the reason it's been in my arsenal such a long time.

Is that true? That the 70-200 f/2.8 IS II is not parfocal? I guess I just sort of took for granted that a number of the higher end lenses were parfocal. I do own the f/2.8 non-IS. I also believe my other zooms are parfocal.

I mostly shoot primes but I should keep this in mind for when I shoot zooms. I'd hate to be focusing, then at the last second tweaking the zoom a bit for better composition, not realizing I'm adding a slight softness to the shot.

Uncle Roger suggests that no photo zooms are actually parfocal, at least when considered as a group (i.e., you might get lucky and your copy of a zoom happens to be parfocal...today...with your current sensor resolution...etc.).

https://www.lensrentals.com/blog/2016/03/mythbusting-parfocal-photo-zooms/

There's a reason cine zooms cost ~10x more than photo zooms, and parfocality is one of them.

 

[peoplemerge]

Is that true? That the 70-200 f/2.8 IS II is not parfocal? I guess I just sort of took for granted that a number of the higher end lenses were parfocal. I do own the f/2.8 non-IS. I also believe my other zooms are parfocal.

I mostly shoot primes but I should keep this in mind for when I shoot zooms. I'd hate to be focusing, then at the last second tweaking the zoom a bit for better composition, not realizing I'm adding a slight softness to the shot.

I admit I haven't tested other Canon 70-200/2.8L lenses other than mine, but it's consistent with reports I've heard. I tested it by shooting wide open on my then-Canon 5Dii at 70, 100, 135, and 200 marks wide open at closest focus and 10m distance. Subject was my living room. I focused at the 200mm position and pixel-peeped the results in center and corner. Sure seemed parfocal at 20mpx! Zoom while recording video always looked splendid at 1080P (2 megapixel FTW).

The reason I think concerns still photo history. At the dawn of the computerized lens design age http://blog.camera-wiki.org/2012/03/13/vivitar-historical-research-part-1/ when manual focus was the only game in town, the incumbent major brands Canon, Leica, Pentax, Nikon,,, made carefully-engineered zooms that were all parfocal. (Caveat: I was too young to hold a camera back then, and I'm not an optical engineer this info fits my research.) In that era, pros would zoom all the way in, focus the split image, then zoom out to compose. Challengers Vivitar, Sigma, Tamron, etc discovered by relaxing the requirements allowing varifocal and variable-aperture lenses, they could produce lighter and sharper lenses than the incumbents.

Fast forward to autofocus days, it no longer was a requirement for a lens to be parfocal since people relied demanded fast and accurate autofocus first, so little by little, they stopped making compromises required to achieve the "true zoom" (parfocal).

Most zooms from the past are slow, dim, heavy, and flawed. Pro zooms for their day produce ok images -- I'd say comparable to consumer zooms of today in IQ, but with a very different color rendition, less crisp.