why can Canon make a 24/1.4 lens for the EOS... whereas Leica can't/hasn't

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Hello, I was just thinking about how nice it would be to have a 28 or 24 lux... Canon makes a 24/1.4 and Nikon makes a 28/1.4... why hasn't/can't Leica do this with the M? I thought it was easier to make wide angle lenses for rangefinders then for SLRs... M users are obviously speed hungry and I am sure there would be many takers... the 28 cron is nice, but i would sure be more interested if it were a lux, or even better woul be a 24 lux. Am i dreaning, is it just not possible, or what?

-- Matthew Geddert (geddert@yahoo.com), April 02, 2002

Answers

As technology now stands, the lens' front element would most likely block the viewfinder to much. Which is not a problem that SLR lens designers must contend with.

-- Marc Williams (mwilliams111313MI@comcast.net), April 02, 2002.

Hey, that was exactly the same question I had too. I just never had the guts to ask it however here.

My theory is that we know that the diameter of the front element of the lens is equal to the focal length/largest f-stop of the lens. For the Noctilux has to be equal to 50 mm on the front element which is 5 cm. That's why the lens has to be dang heavy to gather all that light! :)

So basically for an extremely wide angle lens of 21mm f1.4 the diameter of the front element has to be 21/1.4 mm which is not too hard to make in practice. However, I have to divulge what is Leica is up to.

I really do believe that Leica is planning those fast wide angle lenses but they REALLY want to make sure that those lens are optically worthy of the lens. I remember seeing a Canon 50mm f1.0 shot wide open and it looks so crappy compared to the Leica Noct shot that I am so grateful to rid myself of the Canon system to be honest. After all, I just believe that Leica is a patient company and they aren't going to throw something out in the test field without making sure that problems do occur.

After all, the major dilemmas of fast wide-angle lens are major problems with vignetting because of the heavy curvature of the front element and thus more light bending occurs at the edges with heavier diffraction. It's no surprise that the Summicron will be optically superior at the edges than the Summilux in most shots.

Personally I would rather handhold a lower shutter speed with the Leica M3. That's the point of Leica is to not to just shoot at max. aperture but also at slower speeds than a SLR which can't handle 1/4- 1/15 sec. (and I have held those perfectly)...

So once Leica figures out the vignetting problem with fast wide-angle lenses, I believe strongly that we will see a 35mm f1.0 or 21mm f1.4 lens someday. Just pray and be patient I guess.

-- Alfie Wang (leica_phile@hotmail.com), April 02, 2002.


Yeah, right.

Ain't no pigs flying over my house and the weather report I received from Satan himself says it's still REALLY hot down there.

-- Keith Davis (leica4ever@yahoo.com), April 02, 2002.


Marc, the size of the front element being too big is something i hadn't considered, i bet that is what it is... for all practical purposes a Leica M can't really deal with a lens that has a filter size larger then 60mm... the Nikon uses 72mm filters, and the Canon 77mm filters... but, this has a lot to do with incorporating AF into the lenses, as well as the retro-focus design needed to allow for a swinging mirro... and just look at the difference between a noctilux (60mm) and Canon's 50/f1 (72mm)... couldn't this same difference in size be made by moving from retro-focus SLR designs to RF designed lenses?

-- Matthew Geddert (geddert@yahoo.com), April 02, 2002.

1) A 24 'lux for the Leica M still has to be a mild retrofocus design (and hence large) to leave space behind the lens for the meter to work. So it would be AT LEAST as big the 24 Elmarit - plus some size increase for the extra 2 stops of speed. The 24 2.8 is 55mm, so a 24 1.4 would be not much smaller than the Nikon/Canon designs (but probably a little shorter).

2) A 28 f/2 Summicron is equal to a 28 f/1 Noct SLR lens in terms of effective speed, since it can be hand-held 2 shutter speeds slower than an SLR (no mirror shake - and I do it all the time, so don't yammer about it). CaNikon HAVE to build really fast lenses just to compensate for the SLR's weakness in this area.

3) Keep hoping! - 2 years ago folks were saying "Why can't Leica build a 28 f/2 lens! Nikon and Canon have them!"

-- Andy Piper (apidens@denver.infi.net), April 02, 2002.



My theory is that we know that the diameter of the front element of the lens is equal to the focal length/largest f-stop of the lens. . .

So basically for an extremely wide angle lens of 21mm f1.4 the diameter of the front element has to be 21/1.4 mm which is not too hard to make in practice.

It's not that simple. For wide angle lenses, the angle of view and angle of coverage require a MUCH larger piece of glass than your theory suggests. I have a 35mm/f3.5 lens for my 645--the front element is nearly 70mm wide, not 10mm.

-- Mike Dixon (mike@mikedixonphotography.com), April 02, 2002.


Exactly so. Focal Length/f# gives the diameter of the iris as seen through the front element; not necessarily the front element diameter, which may well be larger.

-- Bob Fleischman (RFXMAIL@prodigy.net), April 02, 2002.

2) A 28 f/2 Summicron is equal to a 28 f/1 Noct SLR lens in terms of effective speed, since it can be hand-held 2 shutter speeds slower than an SLR (no mirror shake - and I do it all the time, so don't yammer about it). CaNikon HAVE to build really fast lenses just to compensate for the SLR's weakness in this area.

Sorry to yammer about it but actual practice, with the way most people use 35mm cameras (handheld), this is hogwash. Yes, there may be a THEORETICAL advantage of less vibration in the rangefinder which SHOULD lead to sharper pictures at any given shutter speeds, which can be extrapolated to allowing longer handheld exposures vs SLR. The problem is that with longer handholding, you are then introducing another source of unsharpness - your own shaking. This myth of "two more stops of handholding" is perpetuated by people who assume that that the presence or absence of a flipping mirror is the only variable, and in the real world it's only one of many (including but not limited to photographer movement, subject movement, etc). I'll take the faster lens anyday, regardless of platform.

-- Anon Terry (anonht@yahoo.com), April 03, 2002.


To those Doubtful Thomases,yup its true,Leicas can be used at really slow speeds.I get at least one sharp photo out of 6 at 15th and 8th! I get unsharp photos reguklarly on Slr at much higher speeds... Try a few longer exposures.You will see difference. As for the lenses mentioned,could one imagine the cost?!!i cannot afford used lenses never mind some super aperture ulta wide angle. I know I'm in the minority here,with folks with lots of equipment,Hassies,Linhofs,Sinars and battery munching Nikons and Canons.Actually I use a EOS for pro work.The 2000! I wish Leica would think of a more affordeable range.I do not need APO though my 135mm is in reality so.Its stunningly sharp and not a real advantage in portraiture!

-- jason gold (leeu72@hotmail.com), April 03, 2002.

Having moved to the M6 from a 20-pound Nikon N90s with SB-26 flash and motor drive (with 12 AA batteries to run everything), I can say that I am much better at obtaining sharper photos at slow shutter speeds.

Regarding the debate about obtaining sharp images with hand-held, slow shutter speeds, doesn't this aguement go against what the B&W "fine art practitioners" are after? I still can't understand paying $2,000 for a super-duper Leica lens with APO or ASPH properties and then purposely trying to get blurred, out-of focus, poorly exposed photos in odd compositions, and calling it fine art. I'm not criticizing anyone's style of art or how they sepnd their money, but I find it amusing that some people think that Leica rangefinders are only meant to be used in this manner. I've got a 40 year old Voigtlander Vitoret with an un-coated lens that'll do the trick in this case. Or maybe a pinhole camera made out of an old Quaker Oats box.

War correspondents grabbing a photo while on the run - maybe a blurred photo is understandable. But if I invest in expensive Leica gear, then you can bet my investment in film and processing will be matched with every effort on my part to get the sharpest, best exposed photos possible. And with my SF20 flash and the M6TTL, I've got some nice family photos that may better than I could have gotten without the TTL capabilities. It's nice to use if you've got it.

And all this time I've been editing out poorly focused, composed and/or exposed E-6 slides that were actually fine art!

-- Steve Brantley (sbrantley@mail.commerce.state.nc.us), April 03, 2002.



First of all, anybody who has been reading Erwin Puts (gasp) will know that it's harder to design lenses for the M than the R because the opening of the M mount is smaller than the R. Retrofocus is no longer the problem it was in the past. Space is more important.

One more thing...there's a difference between maximum aperture and maximum USABLE aperture. What good is f/1.4 if it isn't usable?

-- Bud (budcook@attglobal.net), April 03, 2002.


thanks to everybody for your responses. I guess talking about this will have little if anything to do with Leica creating such lenses (if it is in fact possible), but i was just frustrated about the lack of a fast wide angle lens. My ideal lens set up would be a 24lux, and i would prefer it to a 35lux, which will likely end up being my next lens because a 24elmarit is just too slow for me.

I have to respectfully disagree with the people that say they can always get tack sharp photos at 1/4 or 1/8 of a second, even 1/15... unless you don't have a pulse, images just won't be sharp at these speeds unless you get lucky (which certianly does happen every now and then)... would you shoot only at 1/15 for a client? I thought not.

-- Matthew Geddert (geddert@yahoo.com), April 03, 2002.


The EOS lens mount opening is the largest in 35mm photography. Ever seen the exit pupil of the 85mm f/1.2L? It takes up every square millimeter of that opening--so much so that the the rear element group has to be notched to fit the electrical contacts.

-- Peter Hughes (ravenart@pacbell.net), April 04, 2002.

I for one would be happy with a 24mm Summicron, which would likely be a better balance of size/weight/speed/performance.

Strangely, Leica has not really made this focal length much of a priority, even for the R system. (I believe the 24mm Elmarit R is based on a Minolta optical design.) Since I never got into 28mm, the lack of a truly fast 24mm in the Leica stable is a drag.

Random side comment: I can't speak for the Canon 50 f/1.0, but both the 35mm f/1.4L and 85 f/1.2L are superb optically. Canon's 24 f/1.4 is soft wide open but improves a lot at f/1.8.

-- Gary Voth (garyvot@vothphoto.com), April 05, 2002.


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