Great explanation Wayne! Yes, there is certainly some lens has high
sharpness but may not have very high resolution although sometimes
they are related. I would like to have a lens with high resolution
than sharpness but some people may prefer the latter one.
In MTF, the percentage contrast at 20lp/mm and 30lp/mm are mostly
likely indicate the contrast on print. While the higher line number
will indication more on the resolution, unfortunately I have never
seen MTF test at 50-60lp/mm. In Modern photography test, they have the
resolution data, I think it mean the line is just distinguishable.
The 35-70/3.6 is a tipical example of high resolution and low
sharpness lens.
C.H.Ling
Wayne Harridge wrote:
>
> > John Hudson <jahudson@xxxxxxx> wrote:
> >
>
> > Can someone out there please tell me whether "high resolution" and
> > "high
> > contrast" are one and the same and if not how it might be possible to
> > have a "high resolution" and "low contrast" lens or vice versa
> >
>
> Yeah, these things get bandied about willy nilly. To compare 2 lenses with
> respect to resolution and contrast you need to consult the MTF curves for each
> lens.
>
> If you do this you can determine:
>
> 1. For a specified resolution (e.g. 40lp/mm) which lens has the higher
> contrast.
>
> 2. For a specified contrast (e.g. 50%) which lens has the higher resolution.
>
> It makes little sense to say lens A is a high contrast lens while lens B is a
> high
> resolution lens.
>
> Wayne Harridge
>
> http://members.optusnet.com.au/~w_harridge
>
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