Canon Patents

Patent: Canon EF-M 15-45mm f/3.5-5.6 IS STM II

Canon continues to submit patent applications for an improved EF-M 15-45mm f/3.5-5.6 IS STM. The current version is inconsistent at best, some people get a great copy, but more often than not,  one gets a poor copy.

This new design seems to use 12 elements instead of the 10 in the current design. The patent also touches on improved AF performance from the EOS M kit lens.

Japan Patent Application 2018169618:

The zoom lens used for an imaging device is a wide field angle, and the whole lens system’s being small and a focus lens group can perform focusing at high speed by a small light weight, and, moreover, it is strongly requested on the occasion of focusing that there are few aberration variations etc. In order to make a focus lens group into a small light weight, it is necessary to lessen the composed lens number of sheets of a focus lens group. However, when the composed lens number of sheets of a focus lens group is lessened, the residual aberration of a focus lens group enlarges. For this reason, an aberration variation enlarges on the occasion of focusing, and it becomes difficult to obtain optical performance with a good rear spring supporter from a long distance to the object distance at large [ to a short distance ]

mirage

EOS RP
Jul 31, 2018
297
111
about time they improve that lens. At the minimum, 15-45 Mk. II should be on par with the discontinued EF-M 18-55 (in overlapping FL range).


Edit: not "Mk II", because f/5.6 vs. f/6.3 on long end.
 
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mb66energy

EOS 6D MK II
Dec 18, 2011
1,207
141
Germany
www.MichaelBockhorst.de
Maybe my second M50 to buy will be ordered with this lens if it enters the light of the real market! Good to see f/5.6 compared to f/6.3 - I hate these lower than 5.6 max. apertures!
The EF-M 32 has some addiction potential so I need a second M50 for other lenses!
 

LSXPhotog

EOS RP
Apr 2, 2015
330
141
www.diossiphotography.com
Hopefully the new lens improves the variation on each copy. My first two copies of the current 15-45 had tremendous decentering! It was like the left side of the frame was at a different depth of field in some photos, but it turned out that it was simply a shifted focal plane. I have a good copy now! But wow, I thought it was just a garbage lens at first. It's convenient for snapshots/video and when selling the camera, not much else.
 

mirage

EOS RP
Jul 31, 2018
297
111
you are right! No Mk. II but rather .... "2nd coming of an EF-M 15-45 lens". :)

Anyways, important would be for this patent turning into a "real product" soon with very noticeable improvement in IQ and copy variation over the current 15-45 kit zoom. :)
 
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pj1974

EOS 7D MK II
Oct 18, 2011
589
47
Adelaide, Australia
Hopefully the new lens improves the variation on each copy. My first two copies of the current 15-45 had tremendous decentering! It was like the left side of the frame was at a different depth of field in some photos, but it turned out that it was simply a shifted focal plane. I have a good copy now! But wow, I thought it was just a garbage lens at first. It's convenient for snapshots/video and when selling the camera, not much else.
I bought a 2nd hand copy of the EF-M 15-45mm STM lens, and thankfully have a good copy. Very sharp in centre, and quite sharp at each of the edges too at all focal lengths. I really love the 15mm wide end, and 45mm tele end is 'ok' for some reach... but oh how I wish it had more reach, like my EF-S 15-85mm ... but hey, which is obviously a much larger lens.

From reading user and pro reviews online, it does appear copy to copy variation does exist for the 15-45mm lens. I have an EF-M 18-55 lens too, which is similarly sharp - with notably better build quality, but not as compact / convenient. In terms of IQ and range, the 18-150mm is the pick of the bunch, though significantly longer (again).

The 15-45mm is a great one lens option is wanting to keep things as small / light / portable as possible, with decent to good IQ, on e.g. my M5 (or my M10 as an option too). The f/6.3 vs f/5.6 doesn't really make that much difference. Particularly given that DPAF can focus at narrow apertures ok (though of course the lower the light, the brighter one wants a lens to be). That's why most often in low light I use my primes (e.g. Canon EF-M 22mm f/2 or Samyang 12mm f/2). That another patent for a 15-45mm is around is perhaps more experimental than production at this stage.

PJ
 

Bob Howland

EOS 7D MK II
Mar 25, 2012
428
25
Wouldn't inconsistency in image quality indicate a manufacturing problem, not an optical design quality? How does a new design with a new optical formula correct a manufacturing problem?
 
Reactions: pj1974 and Aaron D

Sibir Lupus

EOS M2 + EOS M10
Feb 4, 2015
80
25
35
Hopefully, they are preparing this lens as the new kit lens for the M5 and M50 MkII's.
The M50 just came out this year, so I doubt a M50 Mark II is right around the corner. My guess is that this new EF-M 15-45mm lens will be the one included on the M5 Mark II and M6 Mark II, and/or the M200
 
Reactions: pj1974

mb66energy

EOS 6D MK II
Dec 18, 2011
1,207
141
Germany
www.MichaelBockhorst.de
Wouldn't inconsistency in image quality indicate a manufacturing problem, not an optical design quality? How does a new design with a new optical formula correct a manufacturing problem?
Maybe it is a problem to adust the current lens formula - optics and the corresponding mechanical parts - at low cost.
What about another design which is more tolerant to deviations from perfect alignment is cheaper compared to better adjustment of the old design?