[Leica] Photodo again

[Erwin Puts <imxputs@knoware.nl>]

David wrote in part:
>OK. Is there ANY information of relevance within the test report section
>of Photodo.com? If you discard everything that is "weighted" -- as the
>weightings are hopelessly malformed -- then are the raw MTF graphs
>themselves of value?
>And how come they've posted the Apo 100R twice, once with great
>(graphed) performance at 2.8 and once with cruddy performance at 2.8?

This is a sensitive topic as many persons on this list seem to value the
Photodo results.
I am not against weighting itself (Chasseurs also uses a weighted formula),
but the specific weighting of Photodo (center is most important, 20lp/mm
are most important, apertures of 4 and 8 are important) are not relevant
for practical Leica testing as you would value in Leice lenses its
performance wide open and at 2,8 and at 10 lp/mm and 40 lp/mm equally
balanced and in the field as important as on axis. Furthermore closeup
performance, flare reduction and a host of other parameters not in the
photodo eqation.

Why the APO100 twice? Ask them!I discussed their MTF testing at length with
the person responsible for the MTF tsting and he told me that they are in
such a hurry to get all lenses tested that mistakes might be  unavoidable.

So the choice is really yours: The Ealing equipment they use is no longer
in vogue with Leica and Zeiss as they use computer generated MTF results
which are better than the Ealing data and Photodo is in a hurry and they
miss much important info.
Or you use as example my results which are very slow in coming as I use a
lens for at least a month in all kinds of situations and with three
different testing method). I also take into consideration all other aspects
mentioned above. But is is not my ambition to test every lens on the market
as soon as possible.


Erwin