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02-16-2010, 07:57 AM   #16
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I liked the format of the tests but have a few points where there are things that should really be addressed.

First of all, we are dealing with lenses at different focal lengths, and this makes part of the comparison difficult, i.e. what is the best approach, camera from same point or same magnification of primary subject. I don't know.

second, in the CA comparisons some of the images were not focused at the same depth, virtually nullifying the results. This is probably human error however, there should always be multiple shots taken in a test, and pick the best focus from each shot to insure the best possible is presented for all lenses.

In the side by side comparsions, all the lenses were shown wide open and compared side by side that way.

I feel that there should be shots taken at each aperture available, but where a lens is not fast enough, that shot is left blank.

clearly it is not correct to compare for example the 50-135 at F2.8 against an 85mm F1.4,

there should also be a set of tests at the longest minimum focus of all lenses. (Let's say 1.5 meters as an example) and also at perhaps a realistic shooting distance of 20 meters for a subject)

overall the idea is good, but just needs some refinement.

02-17-2010, 03:02 AM   #17
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Ton français est très bon
Your french is good (better than my english...)

No conclusion on the 50-135 in the second test cause the zoom was include in "bonus" for the test chart, CA's...and as you see, in the second part, we have a lot of picture à f/1.4 o f/2...and the zoom is...at f/2.8 But in my opinion, this 50-135 could be a good portrait performer. But is really to big for that and (the model says) it's agressive with the big harsh hood etc...
02-17-2010, 07:58 AM   #18
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QuoteOriginally posted by Lowell Goudge Quote
I liked the format of the tests but have a few points where there are things that should really be addressed.

First of all, we are dealing with lenses at different focal lengths, and this makes part of the comparison difficult, i.e. what is the best approach, camera from same point or same magnification of primary subject. I don't know.

second, in the CA comparisons some of the images were not focused at the same depth, virtually nullifying the results. This is probably human error however, there should always be multiple shots taken in a test, and pick the best focus from each shot to insure the best possible is presented for all lenses.

In the side by side comparsions, all the lenses were shown wide open and compared side by side that way.

I feel that there should be shots taken at each aperture available, but where a lens is not fast enough, that shot is left blank.

clearly it is not correct to compare for example the 50-135 at F2.8 against an 85mm F1.4,

there should also be a set of tests at the longest minimum focus of all lenses. (Let's say 1.5 meters as an example) and also at perhaps a realistic shooting distance of 20 meters for a subject)

overall the idea is good, but just needs some refinement.

ok for all that.

But you know, we are not professional, and the test was very difficult and long (we are on since early december...)





""clearly it is not correct to compare for example the 50-135 at F2.8 against an 85mm F1.4, ""

We just make this for one thing: to show how we can obtain different result with a fixed 85 in comparaison of a zoom... Learn french (it's precised in the test)
02-17-2010, 08:48 AM   #19
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QuoteOriginally posted by fourmiX Quote
ok for all that.

But you know, we are not professional, and the test was very difficult and long (we are on since early december...)





""clearly it is not correct to compare for example the 50-135 at F2.8 against an 85mm F1.4, ""

We just make this for one thing: to show how we can obtain different result with a fixed 85 in comparaison of a zoom... Learn french (it's precised in the test)
I can appreciate the difficulty.

I tried to organize a "test" of comparative 70-200 zooms, by listing a provisional set of rules, so that individuals could post shots for comparisons. I gave up when people started arguing about the rules.

02-17-2010, 09:36 AM   #20
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Yes, it is difficult, but in the future we would test other lenses ;-)
and i notify your advices for this :-)
02-17-2010, 09:59 AM   #21
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Interesting test. At f1.4 there I saw very little difference between the Zeiss and the Samyang in the center, and at f2 the Samyang actually seemed just a wee bit sharper. The biggest thing I got out of the test though is that I want the FA 77 Ltd more now than ever before.
02-17-2010, 10:00 AM   #22
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Fa 77 is really a stunning lens, i approve
02-17-2010, 12:54 PM   #23
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QuoteOriginally posted by Parallax Quote
Interesting test. At f1.4 there I saw very little difference between the Zeiss and the Samyang in the center, and at f2 the Samyang actually seemed just a wee bit sharper. The biggest thing I got out of the test though is that I want the FA 77 Ltd more now than ever before.
I cannot see that. For me, the Zeiss at f/1.4 and at f/2 is clearly sharper, with better contrast and less colour. The FA 1.8 is clearly sharper wide open, but wide open is already more than 1/2 f-stop down from the other lenses. So at f/1.4 the Leica and the old A* both are much better than the Samyang. Ofcourse the Leica has a much warmer tone, which also will lead to a perceived higher contrast than the colder images of the other lenses. The Samyang performs only in the center at the same level as the old FA*, though the images of that lens are slightly darker, which already lowers perceived contrast. But the FA* is a very good performer over the wholöe image area at f/1.4, whereas the Samyang breaks down very fast.

So, all i all, I think, the Samyang is very clearly the pooerest perfomer of the set. But ofcourse, the moment you take the price tag into account, the value for money is hard to believe.

Ben

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