EXCERPT page containing first few paragraphs. 2024-04-18 15:36:10
UA_SEARCH_BOT_null @ 3.139.107.241
For full access, subscribe here. Or click title to login.

2 Biogon (M9P, Cabin Exterior)

When the Leica M9 first appeared in 2009, I concluded then that the 35mm f/2 Summicron was not a good choice for any kind of flat field test: landscapes, buildings, or anything in which subject detail is at a uniform distance.

The cause is field curvature, as seen in the MTF chart for the 35mm f/2 Summicron-M ASPH, which shows a pronounced wave (dip) in the middle zones which remains significant even at f/5.6. The MTF chart for the 35mm f/1.4 Summilux-M ASPH FLE shows a similar pattern, but its overall contrast is higher throughout at f/2.8 in particular, and it can be afforded some leeway for being a full stop faster lens. By comparison, the MTF chart for the Zeiss 35mm f/2 Biogon shows a nearly flat field almost to the edges of the frame: exemplary.

Article continues for subscribers...

Diglloyd Guide to Leica is by yearly subscription. Subscribe now for about 25 cents a day ($90/year).
BEST DEAL: get full access to ALL 8 PUBLICATIONS for about 75 cents a day!

Diglloyd Guide to LEICA contains in-depth coverage of Leica M system cameras and lenses, with additional coverage of Leica M Monochrom, Leica Q.

Special emphasis is placed on Leica M lenses and certain Zeiss ZM lenses.

Make better images by learning how to get the best results right away.
Save money by choosing the right lens for your needs the first time, particularly the Summilux/Summicron/Elmarit choice and/or Zeiss ZM.
Make better images, a sort of “cheat sheet” saving yourself months or years of ad-hoc learning. Processing parameters are discussed and shown.
Jaw-dropping image quality found nowhere else utilizing Retina-grade images up to full camera resolution, plus large crops [past 2 years or so].
Real world examples with insights found nowhere else. Make sharper images just by understanding lens behavior you won’t read about elsewhere.
Aperture series from wide open through stopped down, showing the full range of lens performance and bokeh.
Optical quality analysis of field curvature, focus shift, sharpness, flare, distortion, and performance in the field.

Want a preview? Click on any page below to see an excerpt as well as extensive blog coverage, for example on Leica.

35/1.4 Summilux-M ASPH
35/2 Summicron-M ASPH
Zeiss ZM 35/2 Biogon
(not to scale)