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Old Sep 27, 2008, 11:15 AM   #1
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I just bought this lens and need to know a few things before i send in for repair (or if it needs it) i tried a few test shots outside at f1.4 and are these supposed to be blurry like this, on the one picture i pointed the lens on the telephone pole, and on the other i pointed at the house in the middle on the roof tiles, the one with the house was about 100ft away and the other around 50ft click on image thanks.


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Old Sep 27, 2008, 3:20 PM   #2
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Some questions. Are you using all points active? And secondly, why would you shoot a landscape scene at F1.4?

Ok, opening up an aperture to wide open usually ends up a little soft.
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Old Sep 28, 2008, 2:57 AM   #3
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KALEL33 wrote:
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Some questions. Are you using all points active? And secondly, why would you shoot a landscape scene at F1.4?

Ok, opening up an aperture to wide open usually ends up a little soft.
I am not shooting landscapes at f1.4 it is just a test to see if anything in the photo should turn out sharp, if you look at this shot taken in my house at f1.4 still blurry i focused on the fireplace, shouldn't at least that be in focus? yes i am using 450D with Evaluative metering, i would also think that someone in here would know about this and could least REPLY.

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Old Sep 28, 2008, 6:04 AM   #4
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I usethe single centralpoint only for focusing and then recompose to avoid the camera focus somewhere I wouldn't prefer. But don't think that could be cause since the camera seems to have focused nowhere, which make them, as you hinted,unacceptable results, imoI wonder if therecould be a profile setting in the menu that woks better for non canon lens (I don't have a canon dslr, but therecentlyunveiled two models are so tempting)..
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Old Sep 28, 2008, 12:36 PM   #5
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bahadir wrote:
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I usethe single centralpoint only for focusing and then recompose to avoid the camera focus somewhere I wouldn't prefer. But don't think that could be cause since the camera seems to have focused nowhere, which make them, as you hinted,unacceptable results, imoI wonder if therecould be a profile setting in the menu that woks better for non canon lens (I don't have a canon dslr, but therecentlyunveiled two models are so tempting)..
Thanks for your reply my friend,, tommorrow morning i am sending the lens to sigma service just to be checked out then they can fix it if there is a problem, but it is wierd that this test i did it looks like it is fine getting really close, it is only at a distance that i think it has a problem but could be my fault as well,


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Old Sep 28, 2008, 5:21 PM   #6
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They seem better, but not asneat as one can expect from a prime lens on a award winning camera, imo! My old Yashica SLR camera had an 1.4 lens on, but I did not have any near ordistant object issues when I properly focused manually since it didn't have AF (auto focus)!Btw, you might havetried the MF..
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Old Sep 28, 2008, 5:51 PM   #7
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Hard to tell from those low resolution test shots.

We don't have exif data on them either.

What kind of sharpening are you using? If processing RAW, what kind of workflow? Basically it's almost impossible to tell anything at all from the shots you posted. And because you think we ought to be able to tells us that you don't really know how to go about testing your lens.

It is odd to be testing f1.4 landscape-type shots at 50 & 100ft. Why are you doing that? Just to test something that you would never use in practice? Why? It seems a bit pointless testing a lens for a scenario you will never use.

Download a test chart or use a ruler/book/newspaper or something at reasonable distances. Mount on a tripod and use mirror lock up and try various apertures. Try to get decent light on the subject.

What do you expect from this lens? What kind of pictures are you going to take with it?




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Old Sep 28, 2008, 11:10 PM   #8
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I agree with Peripatetic. Use a ruler or a piece of paper with a ruler on it. Use the center focus point and focus on a point on the ruler. The results will show you if the lens is focusing correctly and whether or not you have a front or back focus problem with this lens. Unfortunately, the first test you made was useless so it was difficult to effectively respond. I hope this helps.
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Old Sep 29, 2008, 1:10 AM   #9
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bahadir wrote:
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They seem better, but not asneat as one can expect from a prime lens on a award winning camera, imo! My old Yashica SLR camera had an 1.4 lens on, but I did not have any near ordistant object issues when I properly focused manually since it didn't have AF (auto focus)!Btw, you might havetried the MF..
Manual focus gives me the same result arkadas, also it don't look as neat to me also
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Old Sep 29, 2008, 1:23 AM   #10
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peripatetic wrote:
Quote:
Hard to tell from those low resolution test shots.

We don't have exif data on them either.

What kind of sharpening are you using? If processing RAW, what kind of workflow? Basically it's almost impossible to tell anything at all from the shots you posted. And because you think we ought to be able to tells us that you don't really know how to go about testing your lens.

It is odd to be testing f1.4 landscape-type shots at 50 & 100ft. Why are you doing that? Just to test something that you would never use in practice? Why? It seems a bit pointless testing a lens for a scenario you will never use.

Download a test chart or use a ruler/book/newspaper or something at reasonable distances. Mount on a tripod and use mirror lock up and try various apertures. Try to get decent light on the subject.

What do you expect from this lens? What kind of pictures are you going to take with it?



They are right out of camera no sharpening, the outside shots were just a test shot to see if anything would be in focus at f1.4 i know your not supposed to use f1.4 for landscape, but what i do expect from this lens is it to perform like the reviews, it is nothing like that look at my EF 50 1.8 ll when i focus on my fireplace at f1.8 and then look at the 30mm at f1.8, i guess thats all i expect of a lens to perform like it should i just don't understand why companies don't test their lenses before putting them on the shelf.

and here is a test chart i did don't know if it's right though.


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