G vs ZM lens size

A

AlanS

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Can anyone explain why the new ZM lens are so much bigger and slower than the G lens? (21 & 28 focal lengths).
Regards,
Alan.
 
The ZM28 is a bit longer than the G, but the 21/4 is only one of the 21's in the ZM line. The G21 is one of my favorite lenses, partly because of the compactness.

I wonder this too- the ZM25 looks to be similar in size to the ZM21/2.8, and the 25 is one long lens. Seems counter-intuitive to me that a wide angle lens would be so long, but then I'm surely no optical engineer. The ZM21/2.8 uses a much smaller filter (46 vs. 55 for the G21) so that may come into play?
 
Retrofocus

Retrofocus

sepiareverb said:
T

I wonder this too- the ZM25 looks to be similar in size to the ZM21/2.8, and the 25 is one long lens. Seems counter-intuitive to me that a wide angle lens would be so long, but then I'm surely no optical engineer.

I would imagine this is because the lens is a retrofocus design. Perhaps Zeiss had solid state imaging in mind when designing these WA lenses. Certainly the front elements seem to give those design cues awahy in my mind.
Click to expand...
 
I would guess the size difference is due to retrofocal design
to share design and features between M mount and Nikon mount lenses.

Roland.
 
The G lenses don't need a complicated helicoil set up because they are AF?
 
The G lenses are designed for a FILM range finder camera. So the rear element can get as much as nessecary inside the camera. The zm lenses had to b designed with a digital range finder in the future in mind so there had to be a curtain distance between sensor and rear element. That is why I prefer the G line over the Zm line !
So a lot of the elemennts of G-lens is actually inside the camera instead of outside the camera!
 
jaap said:
The G lenses are designed for a FILM range finder camera. So the rear element can get as much as nessecary inside the camera. The zm lenses had to b designed with a digital range finder in the future in mind so there had to be a curtain distance between sensor and rear element. That is why I prefer the G line over the Zm line !
So a lot of the elemennts of G-lens is actually inside the camera instead of outside the camera!
Click to expand...

I doubt that Zeiss will build a digital camera in the near future.

But the ZM lenses came out for Nikon SLRs first, and there is a mirror behind the lens ....

Roland.
 
ferider said:
I doubt that Zeiss will build a digital camera in the near future.

But the ZM lenses came out for Nikon SLRs first, and there is a mirror behind the lens ....

Roland.
Click to expand...
The zeiss nikon are a different story the wide angels are retrofocus design
 
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