Archived posting to the Leica Users Group, 1997/08/29
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To answer to some questions, here are the informations I have about
Chasseur d'Image lens tests.
First, Chasseur d'Images is the leader French magazine (at least the
most sold). They are "amateur" oriented and talk a lot about equipment
and practice.
I've read them for 15 years as well as others magazine, including
american and british ones.
Here is a description of their tests (copied from
http://ue3.ee.nus.sg/photozone/cdi.htm) :
The performance are tested by three methods:
test charts (with a reference well-known lens)
double resolution projector (for contrast, vignetting and distorsion)
MTF-tests up to 200 (!!!!!!) lp/mm
The tests are adopted to the specific lens type.
How to interpret their results:
a weak definition will produce bad image even on 9x13cm
a average defintion will produce a suffcient 9x13 image of a subject but without good details
a good defintion will be sufficient for 13x18 (maybe for 18x24 for classical subjects)
a very good definition will be enough for poster or projected slide
a excellent definition: no comment
The overall performance is rated in stars for performance, Quality/price ratio, Love Factor:
* - weak
** - average
*** - good
**** - very good
***** - excellent
Here is what I think of their tests, copied
from a previous message in rec.photo...
- - You should not take care too much of the Quality/Price ratio. It is
usually low for Zeiss and Leitz lenses. This means mainly that
mainstream japanese lenses are very good and less expensive, not that
it is stupid to buy german. Even CI agree with this.
- - It is not a good idea to give the rating without the comments,
so if you disagree with a result or don't understand it, maybe it is
just a misunderstanding
- - I've checked their tests on Canon (L and non-L), Nikon and Leitz
lenses and read every issue of this magazine for the last ten years. I
don't agree with them on everything and they evolve but they have a
very strong technical background, they are very rigourous, they always
explain their methods and they asnwer to every question in 48H. So I
trust them.
- - In a previous message, someone told me that some of their results on
Zeiss lenses was possibly wrong. I don't know what to think about it.
It is possible but I would be happy to see the result of other tests
on the same lenses.
- - Their opinion on Leica has changed slowly. 15 years ago, they used
to consider that it was too expensive. Now, they appreciate the
mechanical quality of the lenses, and say that the optical quality is
probably the best. So their point of view is: if you can afford it and
want it, go for it. You won't be disappointed and you'll have the
best lenses possible. But other brand make excellent lenses too. For
instance, it seems that nobody in their staff is using Leica equipment.
They don't publish their tests in any electronic form, but several
Internauts have built databases. Just try to search for "lens+test" on
altavista and you'll find them. Or have a look at:
http://i31www.ira.uka.de/~klaus_s/lenses.htm
For instance, here are the results of the tests of the 35mm/2
summicron, the 35mm/2 ASPH and the 24mm/2.8 ASPH:
35mm/2
Excellent = =
Very good = +=
Good = += +=
Average += += += +=
Weak += += += +=
f/2 f/2.8 f/4 f/5.6
+ : quality in the edges
= : quality in the center
Vignetting:
f/2: noticeable 0.7 f-stop
f/2.8: not important: 0.4 f-stop
f/4: negligeable
Distorsion: negligeable
Performances: ****
Q/P: **
Love Factor: ***
Comment:
Very good optically, but we expected better wide open.
35mm/2 ASPH
Excellent = = =
Very good += += += +=
Good += += += += +=
Average += += += += +=
Weak += += += += +=
f/2 f/2.8 f/4 f/5.6 f/8
+ : quality in the edges
= : quality in the center
Vignetting:
f/2: noticeable 0.6 f-stop
f/2.8: not important: 0.3 f-stop
f/4: negligeable
Distorsion: negligeable
Performances: *****
Q/P: ***
Love Factor: ****
Comment:
The best 35mm with the 35/1.4 ASPH. Lot of good points: maniable,
robust...
24mm/2.8 ASPH
Excellent = =
Very good = += += +=
Good += += += +=
Average += += += +=
Weak += += += +=
f/2.8 f/4 f/5.6 f/8
+ : quality in the edges
= : quality in the center
Vignetting:
f/2: noticeable 0.6 f-stop
f/2.8: not important: 0.3 f-stop
f/4: negligeable
Distorsion: 0.5%, noticeable
Performances: ****
Q/P: *
Love Factor: ***
Comment:
Excellent lens mechanically and optically. But too expensive.
- --
Pascal Meheut
pascal@murex.fr