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xaprb
Joined: 28 Jan 2021 Posts: 168
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Posted: Thu Aug 11, 2022 4:38 pm Post subject: Kipon IBECAT Mirror Lens |
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xaprb wrote:
I happened to stumble upon this on the Kipon website:
“We are currently working on our next project, the wide-angle IBEGON lens. With Sony releasing the new full-frame mirrorless A7/A7R camera, we have designed a high-speed telephoto APO mirror lens called the IBECAT, named for its sharp image capture, its lightweight construction and fast glass. Additional lenses are in development for full frame mirrorless cameras, including a tilt-shift lens and a compact fixed focal length lens.”
Source: Dec 2013 pre-announcement of Kipon’s ultra-large-aperture 40mm f/0.85 lens, https://kipon.com/announcement-for-first-40mm-f0-85-high-speed-handevision-lens/
I haven’t found any other mentions of it, so perhaps it went no further than a design or conceptual stage. Around that time Kipon (and their Handevision partnership with the German optics firm IB/E) was also seemingly having a bit of difficulty executing on their plans, so perhaps they decided this was too ambitious and pared back their plans to focus on the vaguely Leica-alike lenses they did end up releasing.
To my knowledge, assuming the IBECAT was actually an original design, this would have been one of the most recent truly new product development announcements for consumer-oriented mirror lenses.
The other ones I’m aware of are from Kenko/Tokina. From what I know, roughly around 2012 Tokina released a 300mm mirror lens for Micro Four Thirds (and there’s what appears to be a similar lens for Sony E without any electronics, both unbranded and branded Albinar) and then more recently, they’ve released 400mm f8 and 500mm f8 mirror lenses. I’m not sure these are new designs, but they might be.
The other mirror lens announcement I’m aware of in the last decade is the IRIX Space lens, but it’s also not clear to me that this ever went past a CAD drawing; nor that it’s an original design. (And it didn’t seem targeted at consumer usage.)
I think, but I’m not sure, that all of the mirror lenses coming out of Korea and China in the past 15 years or so have been older designs that have simply been passed around from maker to maker as conditions have shifted, Korean optics have gained status and cost, and Chinese optic factories have gained the ability to manufacture to very high standards (e.g. some of the premium costly Panasonic Leica Micro Four Thirds lenses are made in China now, whereas they were made in Japan when initially introduced). By that, I mean that I think mirror lenses from e.g. Samyang, Rokinon, Vivitar etc that were made in Korea around the beginning of that time frame are now essentially “the same” but now made in different factories in China.
Disclaimer: this is not intended to imply anything about quality, not meant as any kind of complaint or lamentation or political commentary. I don’t see any evidence that Chinese optics are inferior in 2022, as attested by the superb performance of my made-in-China Panasonic Leica 100-400mm Micro Four Thirds lens, or any of the dozens of third-party lenses I’ve bought from makers like 7Artisans, Meike, TTArtisan, et al. I’m simply observing that the manufacture of these mirror lenses have migrated geographically, but appear to be essentially the same optics, during that time period. And thus I don’t think they’re “new mirror lenses” per se.
I may not be correct on some of the above. I’m curious what others can add! |
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RokkorDoctor
Joined: 27 Nov 2021 Posts: 1250 Location: Kent, UK
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Posted: Thu Aug 11, 2022 7:52 pm Post subject: |
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RokkorDoctor wrote:
What would be interesting were if anyone made a mirror lens with the secondary mirror offset outside of the main front lens. You would then still have reasonable compactness but it would also allow for a regular adjustable aperture with regular bokeh rather than the doughnut bokeh. I suspect this would require the main mirror to be an asymmetric aspherical design though for preserving IQ.
Adjustable apertures can be put into regular catadioptric mirror lenses anyway if really necessary, but apart from a vague recollection that there was one such mirror lens with adjustable aperture I think no one else bothered on account of the tricky engineering required. And the doughnut bokeh would become even more pronounced. _________________ Mark
SONY A7S, A7RII + dust-sealed modded Novoflex/Fotodiox/Rayqual MD-NEX adapters
Minolta SR-1, SRT-101/303, XD7/XD11, XGM, X700
Bronica SQAi
Ricoh GX100
Minolta majority of all Rokkor SR/AR/MC/MD models made
Sigma 14mm/3.5 for SR mount
Tamron SP 60B 300mm/2.8 (Adaptall)
Samyang T-S 24mm/3.5 (Nikon mount, DIY converted to SR mount)
Schneider-Kreuznach PC-Super-Angulon 28mm/2.8 (SR mount)
Bronica PS 35/40/50/65/80/110/135/150/180/200/250mm |
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calvin83
Joined: 12 Apr 2009 Posts: 7547 Location: Hong Kong
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Posted: Thu Aug 11, 2022 10:12 pm Post subject: |
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calvin83 wrote:
I would like to have an AF 250-300mm mirror lens with modern aspherical design. _________________ https://lensfever.com/
https://www.instagram.com/_lens_fever/
The best lens is the one you have with you. |
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xaprb
Joined: 28 Jan 2021 Posts: 168
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Posted: Fri Aug 12, 2022 10:09 am Post subject: |
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xaprb wrote:
See http://forum.mflenses.com/clear-view-hama-300mm-f5-mirror-lens-t83201.html for one mirror lens with adjustable aperture. |
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RokkorDoctor
Joined: 27 Nov 2021 Posts: 1250 Location: Kent, UK
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Posted: Fri Aug 12, 2022 12:41 pm Post subject: |
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RokkorDoctor wrote:
OK, so my memory wasn't playing tricks on me, there was at least one. Thanks for the link!
As I suspected and suggested already, the images in that topic confirm that closing down the aperture makes the doughnut bokeh worse. _________________ Mark
SONY A7S, A7RII + dust-sealed modded Novoflex/Fotodiox/Rayqual MD-NEX adapters
Minolta SR-1, SRT-101/303, XD7/XD11, XGM, X700
Bronica SQAi
Ricoh GX100
Minolta majority of all Rokkor SR/AR/MC/MD models made
Sigma 14mm/3.5 for SR mount
Tamron SP 60B 300mm/2.8 (Adaptall)
Samyang T-S 24mm/3.5 (Nikon mount, DIY converted to SR mount)
Schneider-Kreuznach PC-Super-Angulon 28mm/2.8 (SR mount)
Bronica PS 35/40/50/65/80/110/135/150/180/200/250mm |
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PBFACTS
Joined: 24 Dec 2008 Posts: 564
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Posted: Tue Aug 30, 2022 11:11 am Post subject: |
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PBFACTS wrote:
RokkorDoctor wrote: |
OK, so my memory wasn't playing tricks on me, there was at least one. Thanks for the link!
As I suspected and suggested already, the images in that topic confirm that closing down the aperture makes the doughnut bokeh worse. |
1-It is NOT adjustable aperture as we usually think to / It does not change dof or bokeh
It just reduce the front lens size as would do a pierce cap (ie: sigma 500/4 which could be reduced to f:8 with a cap) therefore increasiing the iq =making the donuts worse/more precise)
2- A Mirror lens with TRUE adjustable aperture DID exist in ~1985 (i do not remember me the tm) but was bigger than most refractor lenses and x time bigger than the vivitar/perkin 600mm solid cat
The trick is that the second mirroris IS NOT in the same axis than the first mirror (a little bit as the viewfinder of the polaroid sx-70) _________________ OM USER .. I KEEP/USE:
Om2 sp + T32 (grip/filter/zoom) + T8
+ Zuiko 16mm 3.5 / 55mm 1.2 / 65-200 4/ x1.4
+ Sigma 8mm 4.0 / 14mm 3.5 / 18-35 3.5-4.5
+ Tamron 35/105 2.8
+Tokina 150/500 5.6
+ Kiron 105/2.8 macro 1:1
+ Vivitar S1 90/180 falst field macro
+ 2x Doubler HR7
>>I SELL: OM10 + OM4ti
+ i sell: OM Md1 + Md 2 + Grip PowerPack + charger
+ i sell: OM Zuiko 24mm 2.8 / 28mm 3.5 / 50mm 1.8 / 50mm 1.4 / 50mm 3.5 macro / 35-70 3.6 / 35-105 3.5-4.5 / 75-150 4 / 500mm / 2xA
+ i sell: OM Kiron 28/105 3.2-4.5 / 1.5 converter
+ i sell: OM Makinon reflex 5.6/300 + Spector reflex (makinon) 500mm
+ i sell: OM Macro panagor extender 1:1
+ i sell: OM Sigma 16mm 2.8 fisheye (last version) / 21-35 3.5-4.2 ot/ 28-70 2.8 /1000mm mirror
+ i sell: Tamron 28-70 3.5-4.5 / 28-80 sp 3.5-4.2 / 28-135 sp 4-4.5 / /28-200 3.5 / 35-135 3..5-4.5 / 90mm sp macro 1:1 2.8
+ i sell: OM Soligor 2x doubler / x3 converte
+ i sell: Soligor FisheEye x0.15
+ i sell: OM Tokina 28/135 4-4.6 / 70/210 3.5 (= vivitar S1 v2)
+ i sell: OM Vivitar 28-70 3.5-4.8 / 28-90 s1 2.8-3.5 / 35-70 2.8-3.8 / 55/2.8 Macro 1:1 (komine) / 70-150 3.8 ot (kiron) / 75-150 ot 3.8 (tokina + 2x matched)
+ i sell : OM cosina 100-500 5.6/8 |
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