If you are registered, you get access to the members only section, can participate in the buy & sell second hand forum and last but not least you can reserve your preferred username before someone else takes it.
How wide do you need to go? And what's your budget? The lenses range from 45mm down to 15mm. There is also a Zeiss 35mm Perspective Control lens (I opted for the Schneider 28mm). And there are some zooms that cover the wide-angle range, too.
The fast lenses were made in Germany and have rather high price tags, even now.
I have the following lenses:
Vario-Sonnar 35-70mm f3.4 (my favourite)
Vario-Sonnar 28-70mm f3.5 (rarely gets used)
Distagon 25mm f2.8
Distagon 18mm f4
Schneider PC-Super Angulon 28mm f2.8
Here is a list of the lenses that were available - as far as I can see, Zeiss no longer keep any data on the old ranges.
I think I'm leaning towards the 25mm or 28mm focal range. Is there a significant difference in the two in terms of IQ? Also how does Schneider glass compare? I actually love Schneider results from my Rollei.
What do you mean by IQ? As far as I'm concerned, it means Intelligence Quotient and refers to a person's level of understanding.
I can't do a like-for-like comparison of the Schneider 28mm lens, as the only Zeiss lens I have of that focal length is the 28-70mm zoom and it would be unfair to compare a zoom against a prime.
The Schneider lens is rare and expensive secondhand as it is a Perspective Control lens. The Zeiss 35mm version is probably rarer still, as the Schneider has adaptors that allow it to fit a range of different camera bodies so more would have been sold. The Zeiss was only available in Contax/Yashica mounts (would there have been a Rollei version?), so you'd had have to be a very keen, and well-heeled, Contax owner to afford one.
I do find that the shift facility of the Super Angulon needs a great deal of bracketing to get a properly exposed image. I really need to carry out some test films to determine by how much the exposure meter settings need to be adjusted to get the correct exposure - they're generally too dark.