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View Full Version : Sigma 10-20 soft?

andyjayh
10-02-2008, 17:32
Asking for a bit of advice here really. Just bought a Sigma 10-20 and I think it is showing signs of being soft on the bottom left side. So I have taken a picture of a flat wall and all I have done is resize and convert to .jpg

Any views on whether this is soft or what you would expect?

http://www.midsussexflyers.co.uk/images/Test/IMG_0507.jpg

File is approx 2m and larger then the forum rules allow to post which is why I link to the img instead.

Many thanks
Joe T
10-02-2008, 17:35
Does seem a bit soft on the left doesnt it? :shrug:
Steep
10-02-2008, 18:32
It's not uncommon for them to be soft round the edges but you need to be careful how you test them, for example in that shot are you sure the camera was absolutely square on to the wall? Try a shot at a mid f/stop like f8 or f9 as well as the f18 you've done.
andyjayh
10-02-2008, 18:51
The camera was tripod mounted and the and I used a timed shot to ensure no shake. It was visually square to the wall but I agree any small misalignment will cause a poor result. However I feel as if other images are showing the same results.

Here is another of the wall but at f4;

http://www.midsussexflyers.co.uk/images/Test/IMG_0509.jpg

And here is another sample image.

http://www.midsussexflyers.co.uk/images/Test/IMG_0384.jpg
foodpoison
10-02-2008, 18:55
Looks a little soft, but is it really noticable?
If you're unhappy, send it back. But if its something that you're worried about for the sake of being worried about, don't.
Canon Bob
10-02-2008, 18:56
It's not uncommon for them to be soft round the edges but you need to be careful how you test them, for example in that shot are you sure the camera was absolutely square on to the wall? Try a shot at a mid f/stop like f8 or f9 as well as the f18 you've done.

Steep...EXIF shows it was at f/8.

One problem with the bricks texture is that the sun will be shading the right side of the surface relief (on the left side of the shot)

Zooming in tight does show a slight left sided weakness at the setting used....not an uncommon occurrance with ths lens.

Bob
SDK^
10-02-2008, 20:38
Other samples i've seen around the internet show the same edge softness - It's normal for this lens.
Cesium
10-02-2008, 21:54
In the Photography on the net - Canon forum a contributor is asking exactly the same question. The opinion is to get a Canon lens (if you are using a Canon that is ;) )
andyjayh
13-02-2008, 19:27
Sent the lens back to Amazon yesterday :(

I think I will spend a little extra and go to Park Cameras and actually try the next lens prior to purchase. If I can't find a good one then I'll have to consider the Canon option, hopefully that won't have to happen.

Need the extra money as saving for a 24-105L :D