Quote Originally Posted by E. von Hoegh View Post
The Apo-Lanthar is most closely related to the Heliar, it is not a Plasmat or anywhere near one. Also, neither the Lanthar/Heliar nor the Plasmats are wide-angle lenses.

The old wide angle lenses such as the Angulon (a "reverse" Dagor type) usually just covered their format, and needed to be stopped down for good sharpness over the entire frame. Newer lenses such as the Super Angulon allow for movements, and will work at a wider aperture.
E., we're partially in small format land. There Apo-Lanthar is a trade name, as is Heliar, and both names (neither 5/3 lenses) include wide angles.

About the old types, agree about the need to stop ancient types down to get full coverage, but modern types also gain coverage on stopping down.

Disagree strongly about the old types' limited coverage. Consider, if you will, f/18 Protars, Ross' f/16 versions, f/14 Perigraphes and f/8 and f/9 Wide Angle Dagors. I have a tiny 45/9 CZJ Goerz Dagor that covers 2x3. It isn't cataloged, I have no idea what its intended format is.

Disagree too that some of the modern types have lots of coverage. My little 38/4.5 Biogon covers a hair more than its intended format; has to cover 80 mm, puts good image in an 84 mm circle (huge difference there, eh?) and the illumination vanishes at 86 mm.

IMO -- not everyone agrees -- the significant differences are that modern w/a types in general are faster than the ancients, therefore easier to focus; that the ones that take advantage of Roosinov's tilting pupil trick have more even illumination than the ancients; and that the modern ones don't have to be stopped as far down as the ancients for good results. On this last point, for example, Rodenstock says that Apo Grandagons are best used between f/8 and f/11.