[OoKU]

Ricoh imaging (Pentax) filed patent of front wide converter lens (x 0.7) for the lens for 35mm full-frame sensor camera.

【公開番号】特開2018-4884(P2018-4884A) click here
【公開日】平成30年1月11日(2018.1.11)
【発明の名称】副光学系

Specification and lens arrangement of embodiment 1
FNO. 2.2
f 28.84
W 39.5
Y 21.64
fB 37.78

WL and ML are wide converter and master (smc PENTAX-FA 35mmF2AL) lenses, respectively.

Ricoh may decide to expand 35mm-FF sensor lens line-up by a converter lens.

---------- Post added 01-11-18 at 05:46 PM ----------

Wide converter (x 0.7) for the lens for 35mm-FF sensor camera?An image on a sensor?So-net???

[Na Horuk]

Is this for the new GR with the curved FF sensor???
Just kidding, don't want to fuel any rumours. Looks like a nice big chunk of glass, but I don't think lots of Pentaxians would buy such a big converter (bigger than the FA 35mm??) when they can get an actual wider lens that weights about the same amount and has no image quality degradation

[stevebrot]

Trying to fathom the market for this...thinking...thinking...thinking...

(time passes)

...thinking...thinking...thinking...

(more time passes)

...thinking...thinking...thinking...

(^C)

...done

Nothing to see here folk...just move on...


Steve

[stevebrot]

Nothing to see here folk...just move on...

For detailed application in English...

JPO Online Translation

The device is a focal length conversion auxiliary lens. There is no specific relation to the FA 35/2 except that the diagrams for the host lens are essentially that of either the FA 35/2 or DA 35/2.4 and the element-by-element text description is specific to the diagram. The converter would provide equivalent FOV to APS-C for FF lenses.

The the object of this invention is as follows.
Even if you are a case where it applies to a main optical system of a high image circle which is made based on the above awareness of the issues, for example, includes the Leica seal, maintain optical performance of a whole system optical system on a high level.
Acquire a suboptical system which can attain a miniaturization.

The quote follows discussion of quality retention with conversion to a smaller image circle. The claim is made that this is accomplished without significant optical aberrations. The bit about "Leica seal" appears to be an artifact.


Steve

---

Last edited by stevebrot; 01-11-2018 at 07:05 PM.

[UncleVanya]

I would expect it to be useful on a full frame gr. Should one be created.

[pinholecam]

If it means that I take 1+1/2 lens (size/encumbrance wise) and means that I have a FA35/2 and a 24mm (that is good IQ stopped down at f8-f11), then I don't see why not.
In fact, I'd get one.

[pentaxfall]

Many companies use patent as bargain chip when dealing other companies. So better to have one.

[Painter]

If there was a compact camera with a 35mm lens wouldn't this also provide a 24.5mm solution much like the Ricoh R1s with its 32mm and 24mm lens.

35mm and 24mm are two very useful focal lengths.

[thibs]

I smell fixed lens 24x36 from RI...
Tiptop 35 to 24mm conversion surely a coincidence (hum).
If it was for 28mm conversion, they'd get to 21mm IMO not between 19 and 20mm. If only for historical/reference reasons.

[Fogel70]

Sony has a similar converter for FE 28 lens on mirrorless for 21mm FL (and also a fisheye converter) so it might not be limited to a fixed lens camera. I might get the UWA converter for my FE28, as it seems like a decent budget UWA solution.

[ogl]

Ricoh may decide to expand 35mm-FF sensor lens line-up by a converter lens.[COLOR="Silver"]

The patent could mean nothing. 95% of patents are the part of R&D.
And as Na Horuk said - no any sense to produce such converter instead of real wide-angle lens

[deus ursus]

Except when you're out shooting with your 35 mm and need something wider for that one shot, it would be nice to have such an adapter to put on instead of changing lenses.

[Fogel70]

Except when you're out shooting with your 35 mm and need something wider for that one shot, it would be nice to have such an adapter to put on instead of changing lenses.

And it also require that lens to be available for customers to buy. An adapter like the will probably require less time to be out on market than a complete new lens (unless the design on a new lens is already ongoing).

[credos4u]

Are you guys sure, that is a "front" converter? hm?

Because a speedbooster or wide-converter as you call it, would make sense,
if you want to attract 645 digital users to buy into FF-Pentax also and drop their Nikon or Canon gear.
because they could use their whole 645 lens line up on FF immediately and dont have to buy a whole new lens park.
...especially if such a converter would do x0.7 you could:
just drop your nikon glass. and experience
for instance,
645 FA 150mm 2.8 would become app. 100mm F:1.9 for FF
645 FA 90mm 2.8 Macro would become app. 65mm F:1.9 for FF
645 FA 75mm 2.8 would become app. 50mm F:1.9 for FF
645 FA 55mm 2.8 would become app. 35mm F:1.9 for FF
645 FA 400mm 5.6 would become app. 280mm F:4 for FF
645 FA 300mm 4 would become app. 200mm F:2.8 for FF

is that a coincidence? maybe. nice thought nonetheless.

---------- Post added 01-13-18 at 01:02 PM ----------

and its not that everybody who owns a 645 has the whole lineup of glass.
Once into Pentax FF , such a customer/photographer would soon buy original DFA K-mount glass as soon as available.
Because despite some minor drawbacks, the image quality of the K-1 for instance(I'm pretty sure other FF bodies will follow), seems pretty much superior to most of the other FF cameras.

So that could be a move to push pro photographers that already use 645 to look into a FF pentax also.

[mannyquinto]

My guess would be a FF curved sensor camera w/ fixed 35mm lens. Why put out a 28mm when most phone uses that focal length? If that is the case, it would not be a GR because traditionally it is a 28mm. What do you guys think?