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Leica 90mm f/2.2 Thambar-M, MTF
Leica does not supply MTF for the 90mm f/2.2 Thambar-M. See the aperture series to get an idea of lens performance across the aperture range.
That makes some sense in that there is a massive amount of spherical aberration wide open which leads to extremely low contrast along with pronounced focus shift with stopping down—be sure to focus at the working aperture through at least f/4 to avoid the focus shift.
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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.
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