I never challenge professional test result by "suspecting" they have
error in focusing or equipment failure although it could happen. That
is only for someone who have no any vaild point to argue say.
C.H.Ling
Larry wrote:
>
> Not useless. All testing available right now to look at has its flaws,
> whether it be
> human innacuracy in focusing on a map, or whatever Norman Goldberg/Herman
> Keppler
> did.
>
> Larry
>
> "C.H.Ling" wrote:
>
> > The list is useless because it only containing the photodo's
> > "weighted" number not because it ignored the "technique and
> > photographer", no lens test will include these items.
> >
> > Photodo's result was discussed here for a few times, MTF curve is
> > useful if you know how to interpret them. But photodo's test has lots
> > of deficiency, just try to name a few here:
> >
> > 1. Photodo only test the lens at infinity.
> > 2. Seems they only focus once for checking the whole frame, high field
> > curvature lens will have very low edges performance in the test but on
> > the field it could be fine in most cases as most our objects are 3D
> > not flat.
> > 3. IMO, the poor weighting method only show how the lens perform with
> > small prints.
> > 4. MTF doesn't cover the lens color accuracy and saturation
> > characteristic.
> > 5. Only one sample is tested.
> >
> > To judge a lens performance is difficult, I'm sure there are lots of
> > other points I have left. MTF is not everything not to mention
> > Photodo.
> >
> > C.H.Ling
> >
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