[Leica] Colour slide films and Leica lenses

[Erwin Puts <imxputs@knoware.nl>]

My remarks about K'chromes suitability as the  testfilm of choice for the
image recording capabilities of modern Leica lenses have been interpreted
as to imply that only with these films the characteristics of Leica lenses
can be exploited to the fullest, thus limiting the use of Leica lenses to
this particular film.
As I said (and will repeat here) I use almost every slide film on the
market (Fuji, Kodak, Agfa) as part of my test reports about slide films for
a Dutch photographic magazine. Invariably I use the Summicron-M
50,Elmarit-M 90 and Tele-Elmar-M 4/135 (now replaced by the AP 34/135) as
the lenses  for testing these emulsions in many different situations. As
standard procedure I expose the Macbeth Colour Checker and use a computer
program to measure the exact Cielab values of the colour patches. Colour
deviation and saturation are measured and compared with interesting
rigeour. Densitometer analysis is also part of the test procedure. I never
trust my eyes to draw conclusions. Of course I leave out part of the
subjective evalution and I also acknowledge, but cannot accomodate the
psychological dimension of colour perception.
All these comparison shots (which include resolution patterns) have
convinced me of the suitability of K'chrome for my testing purposes of
Leica lenses. Many other slide films produce interesting or impressive
results and Leica lenses show their abilities with all these films. But
some are more equal than others.

On colour transmission: shooting with several Leica lenses the same colour
paches and mesuring the values never gave me measurement data to question
the neutrality of transmission of Leica lenses. I am not sure if this
information would be of much value as so many and often uncontrollable
variables are at work here. But it is a point well taken and I will create
a test cycle to some additional research and measurements here.

Erwin