Solms has spoken:

[aizan]

you wouldn't feel the same way if the r-d1 had a lower crop factor. plus you're counting on people going through the hassle of external viewfinders for things as mundane as a 28mm fov, and even a 35mm fov if you're wearing glasses on a .85x body.

.72x ain't king for no reason.

 

[fgianni]

We don't even know yet which choice Leica has made, Francesco.

You are right of course, point taken.
But there is some fun in speculating 😀

 

[jaapv]

The only problem surely is going to be focussing the thing which we all expected anyway. I agree with Ben Z, the scope of the message getting lost in the translation is very great. It's not a lens for me anyway. 90mm is just fine.

I doubt the Dutch importer would have much difficulty translating German. However, I cannot see how that could be either, but then the optical science behind building diffraction limited lenses is esoteric to say the least.

 

[Ben Z]

I don't think we need to be scientists to understand that all existing Leica lenses were designed to focus on the same plane, the same distance from the body flange. So they will all focus on the same plane, the same distance from the body flange in the M8. Just as any lens that could focus on a Nikon F or Canon EOS body focuses on the plane of their digital sensors.

And even if for the sake of argument we suspend common knowledge and sense and allow that the 135 APO doesn't focus on the M8 plane, it would be a simple matter to have the rangefinder cam adjusted so that it does. That would mean it wouldn't focus correctly on a film body, but nonetheless it would be usable on the M8.

 

[jaapv]

As I said, I can't believe this either,I won't be selling mine, and I will be posting whatever (I think great!) results I get, whenever I have the M8 in my hands.....

 

[LCT]

...nonetheless it would be usable on the M8.

Yes but not at f/3.4 with a .72x mag VF is the effective base length of the rangefinder is (most probably) shorter than 70mm.
Best,
LCT

 

[jaapv]

And the 1.25 Okular? Let's hope that fits!

 

[LCT]

With the same RF and a 1.25 magnifier the effective base length would be 69.25 (mechanical base length) * 0.72 * 1.25 = 62.33 mm.
Best,
LCT

 

[jaapv]

Well, at least it is 25 % better.....

 

[Alec]

Since the old Elmarit-M 135mm f/2.8 (11829) with goggles is quoted as compatible with the M8 D [iesel 😉] the view/range-finder system has probably not changed much. My bet is on a x.85 version at first.

I would love to handle the new Apo beast, though, because I cannot imagine better wide-open performance than my 'cheap' Tele-Elmarit...

 

[Ben Z]

Yes but not at f/3.4 with a .72x mag VF is the effective base length of the rangefinder is (most probably) shorter than 70mm.
Best,
LCT

The physical baselength of the M8 rangefinder is the same as the film M bodies, this we know for a fact since the googled lenses will fit. So the adjustment for the cropped fov must be controlled by the finder magnification. If the outermost frameline is the one activated by a 28mm lens, then the finder magnification would be increased so those framlines would frame the correct, cropped view. However if the finder is to have a built-in frameline at the outermost border for the 21mm lens (28mm fov) then they could use the same .72 magnification and simply put in a corrected mask set. Either way there is no reason the cropped sensor necessitates demagnifying to the point that a 135mm lens can't be reliably focused. Leica's only reason for doing so might be to increase the eyepoint of the finder, such as the .58 does.

 

[Mark Norton]

Keep in mind that the bayonet lug of the 21mm currently activates the 28 and 90 framelines and if we are losing the 135mm frame, the 35 will be on its own. I'm wondering whether the zebra coded lens mount for the 21 also changes the lug position so that the frame lines would be 21/35, 28/90 and 50/75.

And then there's the runt of the litter, the 24mm. Where does that fit in?

There's so much about the viewfinder and rangefinder we do not know...

 

[LCT]

Due to the crop factor which reduces the size of the circle of confusion, a.72x magnification won't be large enough to focus accurately a 90mm lens at f/2 or a 75mm one at f/1.4 if the mechanical base length of the rangefinder remains the same as classic M cameras IMHO.
Best,
LCT

 

[aizan]

expect sales of the 75/2.5 color heliar to skyrocket.

 

[Ben Z]

A 1.33 crop factor amounts to approx. 75% of the 24x36mm frame, yes? I've made crops of as much as 50% from a slide taken with my 90/2 or 135/4 and (ignoring the enlargement of grain) never found one that showed up a mis-focus compared to the full-frame shot enlarged to the same end size.

 

[Bob Ross]

Keep in mind that the bayonet lug of the 21mm currently activates the 28 and 90 framelines and if we are losing the 135mm frame, the 35 will be on its own. I'm wondering whether the zebra coded lens mount for the 21 also changes the lug position so that the frame lines would be 21/35, 28/90 and 50/75.

And then there's the runt of the litter, the 24mm. Where does that fit in?

There's so much about the viewfinder and rangefinder we do not know...

I did read a rumor somewhere that the coding was done by replaceing the mount, so changing the frame lug would be possible and for the 21mm & 24mm it wouldn't affect the film bodies. I did fool around with the .72x frame line pictures from the Leica site, adding the new FOV lines. When I did this, I just left the 28mm frame as the 21mm frame, so there would be three frames. The 24mm could go with the 35mm to keep it company 🙂

 

[humanized_form]

expect sales of the 75/2.5 color heliar to skyrocket.

yep. i also anticipate the 28mm Ultron will become very popular, as it will be the fastest 36mm lens available for the M8.

 

[LCT]

A 1.33 crop factor amounts to approx. 75% of the 24x36mm frame, yes? I've made crops of as much as 50% from a slide taken with my 90/2 or 135/4 and (ignoring the enlargement of grain) never found one that showed up a mis-focus compared to the full-frame shot enlarged to the same end size.

Just a question of math IMHO.
The minimum EBL (effective base lenght) of a rangefinder is given by the formula b' = (e * f^2) / (k * z) where b' is the EBL, e the visual acuity (0.0003 at approx. 1 arcmin), f the focal length, k the aperture and z the circle of confusion (CoC).
For 35mm cameras, the generally admitted CoC value is 0.030mm so taking into account the 1.33x crop factor of the Digital M, the size of its CoC would become 0.03 : 1.33 = 0.023mm.
This way, the minimum EBL for a 90mm lens at f/2 is 53.87mm when the actual EBL of a .72x finder is only 49.86mm.
Would be even worse if calculation is based on a CoC value of 0.025mm (0.019mm with 1.33x crop factor) sometimes associated to Leica lenses.
Best,
LCT

 

[LCT]

This said, we don't know yet which mechanical base length will be chosen for the rangefinder of the Digital M.
Suffice it to choose a larger one a la Zeiss Ikon to resolve most problems i guess.
Best,
LCT

 

[Ben Z]

This said, we don't know yet which mechanical base length will be chosen for the rangefinder of the Digital M.

Yes we do. It's the same as the rest of the M film bodies. We know that because they've already stated that the googled lenses (like 135/2.8 and Macro-Elmar attachment) will work. So the windows have to be the same distance apart. What we don't know is the magnification factor of the viewfinder, which multiplies against the physical (mechanical) baselength to get the effective baselength.