Sigma 10-20mm 4-5.6 Test Images

[Turkasaurus]

Howdy. I just purchased the Sigma 10mm lens for some real estate photog and took a few test shots. I've read that many people have gotten bad copies of this lens that aren't sharp but have returned it for a new copy that was sharp. I problem is, I'm not sure if my copy is as sharp as other "sharp" copies. I took many test shots through all the apertures at different speeds and wanted to get some other opinions on the performance. Below are what I think are the sharpest of my test shots. Please let me know what you think.

1 1/50 F8 ISO 200 10mm

2 1/100 F8 ISO 800 10mm

3 1/50 F9 ISO 400 10mm

4 1/100 F8 ISO 100 16mm

 

[HughGuessWho]

Its hard to tell how sharp they are on here and compression can effect the sharpness, though I think the parts of you examples that are in focus are pretty sharp. I have had the 10-20mm 4-5.6 for several years, use it all the time and am very satisfied with it. Even though I am currently on a Canon L buying kick, I have no real desire to replace my 10-20mm 4-5.6.

 

[kylehess10]

You should post 100% crop examples. It's hard to tell the sharpness of these photos when they're low-res

 

[Turkasaurus]

Would it help to include the direct link to photobucket? Id like to see if they're sharp across the entire image.

 

[sovietdoc]

These don't look very sharp to me =/

 

[rexbobcat]

Is the edge sharpness as terrible as it's said to be with this lens...

 

[fjrabon]

Is the edge sharpness as terrible as it's said to be with this lens...

Well, there's a lot of perspective distortion around the edges at 10mm, as there are with all super wides, which a lot of people confuse with being 'soft'. A lot of it comes from people comparing this lens at 10mm to another lens at 14mm. At 20mm this lens is as sharp around the edges as any wide angle zoom I've found. At 10mm, there are really only a couple of lenses that even go to 10mm, and I don't find any of them to be appreciably softer around the edges or have more perspective distortion than this one does.

People just aren't used to shooting with 10mm lenses most of the time when they get this lens, and they don't understand how to use/minimize perspective distortion.

That isn't to say a few aren't legitimately soft around the edges, but I've used 2 of them now, mine and a friends, and both were as sharp as any wide angle zoom I've ever used around the edges.

 

[TCampbell]

This isn't a good way to test a lens for sharpness.

Get a sheet of newspaper, unfold it (so ti's as large as possible) and tape it to the wall. Put the camera on a tripod and frame in the newspaper. Make sure the camera is level (you don't want it angled up, down, left, or right as this would cause one part of the paper to be closer than the others -- and thus not a "flat" subject such that everything should be in focus.

Shoot some sample photos.

Zoom in on the images you shot and check to see if the newsprint is actually readable. Check to see if the newsprint has color fringing (e.g. letters have a reddish fringe on one edge and a blueish fringe on the opposite edge.)

Note that the focused distance from lens to the center of the paper won't be quite the same as the focused distance from lens to the corner of a newspaper (the focused distance isn't technically a "flat" field -- it has a slight curve to it.) It's generally ok if the corners are just a tiny bit soft on the focus when the center is tack sharp (you'd have to pay a lot more money for a lens that controls that well.)

Also note that most lenses will produce a more crisply focused image at least one or two stops down from whatever "wide open" is for that lens. Also certain focal lengths are usually sharper than others in a zoom (and there's no general rule ... such as the "short" end is usually better than the "long" end -- it completely depends on the lens model.)

As you plan to shoot real-estate, you probably intend to shoot at higher f-stops to increase the depth of field anyway.

As for the difference between a "sharp" copy -- this can actually have quite a bit to do with your camera. See: LensRentals.com - "This lens is soft" and other myths