Canon Mirrorless... Could we see lower f-stop lenses?

[AprilForever]

Suppose canon went and made a mirrorless sort of camera, perhaps with a 2xish crop like most of them out there. Could we see lower f-stop lenses more widely available, especially zooms? My old c-mount 22.5-90 f1.5 as an example: could they not with the better tech of today make a similar zoom for the larger 2xish crop sensor? 16-120 f1.8, maybe? 50-200 f2?

As I am thinking about it,  a 135 f2L on a crop camera would be a wild lens!

[neuroanatomist]

A 50-200mm f/2 lens is a 50-200mm f/2 lens, regardless of whether you put a FF sensor, 1.6x APS-C, or 2x m4/3 sensor behind it.  It would still be 200mm focal length and f/2 meaning a 100mm diameter iris diaphragm, and because you're asking for a zoom lens, it would be even larger, heavier, and more expensive than the current Canon EF 200mm f/2L IS prime (which is 8.5" long and weighs over 5.5 lbs).

Also, keep in mind that one reason for fast apertures is more OOF blur, and you give that away with a smaller sensor.  So, a 135mm f/2 on APS-C behaves like a 216mm f/3.2 lens on FF (in terms of DoF for the same framing), and on a m4/3 the 135 f/2 would be like 270mm f/4.  Obviously, it's a lot smaller than the real 300mm f/4, but wild?  Not so sure about that...

[Mt Spokane Photography]

In the past, Canon cameras with fixed pellicle mirrors used the same lenses. 

If Canon comes out with a consumer mirrorless or pellicle camera with a tiny sensor like Nikon, then a whole new series of lenses could come out.  Since they would also be physically smaller, having a larger aperture would not be likely, I would not expect any f/1.2 lenses for a consumer camera.

BTW, Canon has already patented a adapter to mount a EF lens on a small lens mount for a new camera body, so you would likely be able to use existing lenses, even autofocus and IS until there is be a sufficient number of the new lenses available to cover most focal lengths.  There would likely be two or three lenses at the start.

So, you could use a 85mm f/1.2 as a extremelywide aperture telephoto lens. It might bring up some interesting super long telephoto capabilities due to the extreme crop of a tiny sensor.

[NormanBates]

a smaller sensor allows for faster lenses to be designed for it, but, for reasons already described above, I wouldn't want that

but also: by going mirrorless, you can design a new lens mount with a lower focal flange distance, and that also allows for faster lenses to be designed

for example: a few years ago, leica had these two mounts: leica-M for rangefinders (focal flange distance: 27.8 mm) and leica-R for SLRs (focal flange distance: 47 mm); both used standard 135 film (nowadays: full frame); but they had a 50mm f/0.95 for leica-M, whereas the fastest 50mm for leica-R was f/1.4

[funkboy]

I'm really hoping that Canon will really go out on a limb when they release their competition to the mirrorless wave.  Various execs have been quoted on multiple occasions saying things like "small cameras can still have mirrors; we've done small SLRs in the past".

I think they're playing the waiting game as mirrorless sales have impacted their low-margin compact sector a lot more than their high-margin DSLRs, & I think they want to be last to the party & steal the show with the most attractive entry a competitive price point.  Knowing that such a thing will likely have to be manufactured at massive scale and make them very close to DSLR-like margin, I think we can rule out a Canonet redux à la Fuji or Leica (the V1 does have a metal body though).

I think it'll come down to whether the thing is designed by focus groups & marketdroids or photographers.  Hopefully they really listened to their customers & got a lot of input from CPS members in the early design stages.  With materials and manufacturing science what it is today, I don't think that "profitable consumer camera" and "serious professional photographic tool" have to be mutually exclusive.  But the design will dictate whether they are able to fulfill that.

I've been going over this in my head for a while now, and in all likelyhood I think we'll end up with something that looks like the bastard child of the Powershot G and modern EOS cameras, hopefully with a little bit of AE1 or F1 DNA thrown in for good measure (or perhaps EOS IX if not, ugh).  I believe that they'll stick with the APS-C sensor size just like Samsung & Sony did as they have a lot of R&D invested in their own foundries  for it (though I'd be perfectly happy if they used the Super 35 sensor size as in the C300 :-).  The trick will be that they'll design a new DSLR mount specification that will have a registration distance just long enough to fit the smallest APS-C mirror box they can possibly design inside.  This is pretty consistent with the adapter patent we've seen floating around.

This will allow the use of all their nice EF telephoto lenses with a small adapter, and also allow them to design new non-retrofocus wide angles for the format (has anyone noticed that the newest non-L/TS-E/macro prime lenses Canon released came out in about 1994?).  The smallest APS-C-ish sized frame film SLR was the Oly Pen F & it had a 29mm flange focus distance, so M mount RF lenses probably couldn't be adapted, but at least Canon FD glass could.  A mirror box like this would allow for non-retrofocus ~28mm lenses, & modern lenses around this focal length (from 24 to 35mm) available to mere mortals is exactly what is lacking in the current lineup.

Don't ask me about when, but I'd be very surprised if they don't announce something in 2012...

[dilbert]

Suppose canon went and made a mirrorless sort of camera, perhaps with a 2xish crop like most of them out there. Could we see lower f-stop lenses more widely available, especially zooms? My old c-mount 22.5-90 f1.5 as an example: could they not with the better tech of today make a similar zoom for the larger 2xish crop sensor? 16-120 f1.8, maybe? 50-200 f2?

For those lenses to be affordable to that segment of the market, they would not be designed to work on FF or even APS-C cameras.

Similarly, I'm not sure if EF-S lenses would work with just a mount adapter as some of them extend quite a bit further back than do EF lenses - EF-S lenses may require an short extension tube. I could easily imagine there being a separate EF-S adapter to the EF adapter that was simply deeper to stop the back of the lens hitting the sensor.