"Better"
"Better"
cbphoto said:
better = contrasty and sharp across more apertures, from center to edge. say i need to shoot wide open (ignoring the max aperture difference for the moment). which will provide more snap?
That is certainly helpful, although that is what makes a lens "better" for you. Not necessarily "better" as an absolute yardstick.
It's pretty obvious that the CV 1.5 is likely to be a "better" lens by your definition. For a start, it will be closed down one stop at F2, compared to wide open with the DR. For another, it incorporates aspherical elements and is 40 years younger technology, which means it has the benefit of the latest optical knowledge and design expertise.
However, I own the DR 50, and I once owned the CV 50/1.5. I sold the CV and kept the DR 50. Why? Because it wasn't "better" for me.
While the CV 50/1.5 might be better in terms of resolution and contrast, in terms of flare control, bokeh, contrast, color rendition, etc. I think the Summicron was the better lens, esp. for portraits.
The CV was also much bigger (52 mm instead of 39 mm filters), heavier and blocked more of the viewfinder. Build quality was much lower, it felt cheap, and the lens hood was inconvenient, had to be screwed on over the filter, and it could not be reversed for storage.
To me, the essence of M photography is to be compact and unobtrusive, to use as light and as small a lens as possible for the job at hand. I felt the CV 50/1.5 did not meet these criteria as well as the DR 50.
For these reasons, I sold the CV 50/1.5.
YMMV.
If possible, one should buy lenses on the basis of matching the characteristics of the lens to intended use (incl. how large you intend to print, what type of film you want to use) rather than through Photodo ratings or MTF graphs, or even others' opinions of which lens is better vis a vis another lens.
Choice of lens should be dictated by (a) what you want to shoot (models? landscapes? test charts?); (b) what you value in your pictures (high contrast, low contrast, nice bokeh, etc); (c) how well each lens meets your needs.
A lens is not "better" than another lens just because it has higher resolution, greater contrast, etc. Frankly, the new lenses from Leica outperform the older lenses in almost all quantitative aspects. I know because I have a 90/2.0 AA which I have compared to my 90/2.8 TE. However, the former is big and heavy and the latter is light and compact, so they serve two different purposes.
The former is used for landscapes, portraits of gorgeous models, etc. while the latter is used for travel, street photography, etc. when weight and the need to be discreet are more important than biting sharp resolution.
Thus I would say the 90 TE is better for travel and street photography while the 90 AA is better for model shoots and landscapes, esp. on slide film.
Wai Leong
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