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09-16-2014, 08:57 AM   #256
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QuoteOriginally posted by Mistral75 Quote
Indeed but unfortunately the patented lens is shorter .

Sorry, I am actually looking at a different patent to you -_-, here the link to the one I'm looking at (Pentax patent for a 70-200mm f/2.8 lens | Photo Rumors)


QuoteQuote:
Pentax filed a patent 2012-189817 in Japan for a 70-200mm f/2.8 lens:

  • Patent filing date: October 3, 2010
  • Zoom ratio: 2.82
  • Aperture: 2.9 - 3.0
  • Focal length: 70.21 - 198.32mm
  • Image height: 21.64mm
  • Lens length: 296.16mm
  • 17 images lens group configuration 14
  • 4 ED elements
  • 2 low-dispersion elements
  • Internal zoom and f focusing


09-16-2014, 08:58 AM   #257
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Those two big @ss lenses gotta be FF lenses in my opinion. They are not the compact lenses that PRIC have been releasing for the APS-C line for some time now.
09-16-2014, 09:00 AM   #258
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Notice the image height... 21.64.. that's not enough for a FF, you'd need almost 24mm. If that's the lens they just released, it's not for a Full Frame. It is big enough for APS-c with shake reduction, with room to spare.
09-16-2014, 09:02 AM   #259
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QuoteOriginally posted by normhead Quote
Notice the image height... 21.64.. that's not enough for a FF, you'd need almost 24mm. If that's the lens they just released, i's not for a Full Frame.
Isn't that 21.64mm measurement actually the radius of the circle of enlightenment (as in, the radius of light projected by the lens. If so, it is more than large enough for full frame coverage. Correct me if I am wrong though, information is power.

09-16-2014, 09:02 AM   #260
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QuoteOriginally posted by D1N0 Quote
Just be clear Mistral. What are you saying? This is not a 70-200? Or it is not full frame or there will never be a full frame?
(deep breath...)

I am saying

the patent some here are referring to and/or have provided a (direct or indirect) link to

and which includes embodiments that describe 22 to 30cm-long 70-200mm or 70-210mm f/2,8 lenses for 24x36 sensors

also includes embodiments that describe 15-45mm f/2.8 lenses for 1/1.7" sensors

and happens to be the patent of Pentax Q's 06 Telephoto Zoom 15-45 mm f/2.8.

I am saying

one won't ever hear about this patent in the context of an actually produced 70-200mm f/2.8 24x36 lens. The corresponding embodiments are mere red herrings put into the patent for camouflage purposes.

(exhale... inhale again... pulse back to normal...)

When time comes and Ricoh launch their 70-200ish lens a.k.a. * Tele Zoom a.k.a. Large Diameter Zoom, this lens will correspond to a totally different patent, yet to be published/spotted.

Last edited by Mistral75; 09-16-2014 at 09:12 AM.
09-16-2014, 09:03 AM   #261
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QuoteOriginally posted by Mistral75 Quote
When time comes and Ricoh launch their 70-200ish lens a.k.a. * Tele Zoom a.k.a. Large Diameter Zoom, this lens will correspond to a totally different patent, yet to be published/spotted.
I completely agree with this assessment. If they did release the patented lens it would simply be too massive to be competitive in my opinion.

---------- Post added 09-17-14 at 01:36 AM ----------

Also, when I compared the telezoom to lenses of know quantities (in this case, the 18-135mm), the lens was simply too small to be of the same design.
09-16-2014, 09:07 AM   #262
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QuoteOriginally posted by Joshua A Quote
Sorry, I am actually looking at a different patent to you -_-, here the link to the one I'm looking at (Pentax patent for a 70-200mm f/2.8 lens | Photo Rumors)
It's the same patent, follow the link within the message from Photo Rumors:

Pentax 70-200mm F2.8 ?????????????So-net???

and read

実施例3 [embodiment #3]

ズーム比 2.83
FNO. 2.9
焦点距離 f=15.45 - 26.01 - 43.65mm
半画角 W=17.4 - 10.1 - 6.0
像高 Y=4.65
fB 0.53mm
全長 L=73.00mm
レンズ構成 14群17枚
スーパーEDガラス 1枚
EDガラス 2枚
低分散ガラス 3枚
正負正正の4群ズーム

Of course in the same patent there is also embodiment #5

実施例5

ズーム比 2.82
FNO. 2.9 - 3.0 - 2.9
焦点距離 f=70.21 - 118.15 - 198.32mm
半画角 W=17.8 - 10.4 - 6.1
像高 Y=21.64mm
fB 2.49mm
全長 L=296.16
レンズ構成 14群17枚
EDガラス 4枚
低分散ガラス 2枚
正正負正正の5群ズーム
09-16-2014, 09:09 AM   #263
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QuoteOriginally posted by Mistral75 Quote
Of course in the same patent there is also embodiment #5
This is the patent (or part of the patent I guess) that I was referring to. Sorry if I've frustrated you in anyway, I don't mean to start a flame war over nothing serious.

09-16-2014, 09:11 AM - 1 Like   #264
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QuoteOriginally posted by normhead Quote
Notice the image height... 21.64.. that's not enough for a FF, you'd need almost 24mm. If that's the lens they just released, it's not for a Full Frame. It is big enough for APS-c with shake reduction, with room to spare.
QuoteOriginally posted by Joshua A Quote
Isn't that 21.64mm measurement actually the radius of the circle of enlightenment (as in, the radius of light projected by the lens. If so, it is more than large enough for full frame coverage. Correct me if I am wrong though, information is power.
Yes it is. Image height = radius. Diameter = Image height x 2 = 43.28

Sqrt (24^2 + 36^2) = 43.27

Last edited by Mistral75; 09-16-2014 at 09:18 AM.
09-16-2014, 09:14 AM   #265
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QuoteOriginally posted by Mistral75 Quote
Yes it is; Image height = radius. Diameter = Image height x 2 = 43.28 Sqrt (24^2 + 36^2) = 43.27

I thought so, but it is nice to have someone with more knowledge on that matter confirm that I had the right idea in the first place.
09-16-2014, 09:16 AM   #266
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QuoteOriginally posted by Joshua A Quote
This is the patent (or part of the patent I guess) that I was referring to. Sorry if I've frustrated you in anyway, I don't mean to start a flame war over nothing serious.
Don't be sorry! It's just that manufacturers do not simply patent an optical formula, they indicate a purpose (how to improve such and such characteristics of existing lenses) and the way to obtain such improvements and they illustrate their statements with examples of optical formulas, also called embodiments.

Among this embodiments is carefully hidden the actual optical formula of a future lens; most of the other embodiments, if not all, are just red herrings.
09-16-2014, 09:17 AM   #267
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QuoteOriginally posted by Snappertim Quote
... now the first of the other lens is a rebadged Tokina 70 200 f4 the size is exactly right, its large enough to be full frame but not large enough to be f2.8, ... now the second lens probaly a version of tokina's 80-400 about the same size...
Just look at the lens caps in relation to the front bit - no way is the bigger one the same size as a Tokina 80-400, I had/have one (it's broken) and it is a comparably small lens. I mentioned above that the front diameter of the smaller of the two lenses seems likely to be at 77mm - too big for f4 and what would be the use of a f4 when you have 60-250/4 already?
09-16-2014, 09:20 AM   #268
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QuoteOriginally posted by Mistral75 Quote
Don't be sorry! It's just that manufacturers do not simply patent an optical formula, they indicate a purpose (how to improve such and such characteristics of existing lenses) and the way to obtain such improvements and they illustrate their statements with examples of optical formulas, also called embodiments. Among this embodiments is carefully hidden the actual optical formula of a future lens; most of the other embodiments, if not all, are just red herrings.
All I'm going to say is that you can never be too careful on a forum, though this one seems to be one of the best around in the regard of members not holding grudges.


Also, it's smart on a corporate level for Ricoh to do all this patenting of stuff they'll never release, but it'd be nice to have a more informative road map or some more indicators of what is to come, lens wise that is.
09-16-2014, 09:26 AM   #269
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QuoteOriginally posted by boriscleto Quote
the fa 28-200, da 18-250 & da 18-270.
fa 28-105/4-5.6 [if]
09-16-2014, 09:54 AM   #270
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QuoteOriginally posted by angus Quote
Just look at the lens caps in relation to the front bit - no way is the bigger one the same size as a Tokina 80-400, I had/have one (it's broken) and it is a comparably small lens. I mentioned above that the front diameter of the smaller of the two lenses seems likely to be at 77mm - too big for f4 and what would be the use of a f4 when you have 60-250/4 already?
Yes OK its hard to see what size a object is when you can only see it against other objects the size of which you also do not know, but even if its not the same lens its DNA looks similar, on the larger lens the zoom lock switch is a clear clue as to its origins, the smaller is a rebadged Tokina 70-200 f4 for sure, and the reason for the larger lens is Full Frame the 60-250 is only APSC, and the future is full frame, Sony has just stated it intends to have 20 full frame lens on the market in a few years, maybe the have come to the conclusion if you want to be number one you have to do what the guy at number one is doing Nikon!!
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