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I recently bought a Sony NEX 5N with the standard 18-55mm lens kit and noticed today that it has a high lens distortion (see below). Enabling the option to suppress lens distortion in the setup did not do anything.

It appears in the whole range of the lens; is this normal? And if yes how to avoid this problem? Or is it my fault because the camera is not 100 percent leveled?

18mm 18mm

35mm 35mm

18mm 18mm

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    \$\begingroup\$ This isn't an answer because I don't have any experience with the specific lens in question, but most kit lenses (and indeed most consumer-level lenses) tend to have significant distortion and some or all focal lengths. Controlling distortion usually requires more glass, which makes the lens more expensive. Lightroom (and many other post-processing software packages) can often correct these in post. \$\endgroup\$ Jul 21, 2013 at 16:15
  • \$\begingroup\$ Are you shooting in RAW or JPEG, and what software are you using to post process these images? Mirrorless cameras like this have a great deal of distortion especially at the wide angle side, so you need to rely on software to remove it. If you shoot RAW and use software that doesn't support the camera in particular then yes it will have a ton of distortion. If you shoot JPEG it should be doing it in camera. More info would be helpful here. \$\endgroup\$
    – dpollitt
    Jul 21, 2013 at 16:38
  • \$\begingroup\$ I am actually shooting in RAW+JPEG, however did not use the RAW files. I tried the option to only shoot in JPEG, however had the same result. So would that mean I have to rely on external software for having a good result? Or could it be potentially be a defect in the firmware? \$\endgroup\$
    – Force
    Jul 21, 2013 at 17:00
  • \$\begingroup\$ Even though both distortion and perspective are addressed in the answers, I'm curious to know: which are you referring to? \$\endgroup\$ May 9, 2015 at 15:08

2 Answers 2

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According to a review of the E 18-55/3.5-5.6, the observed pincushion distortion at 18mm seems to be what should be expected of that lens. It's quite noticeable but not much different from other manufacturers' equivalent kit lenses, such as Canon's EF-S 18-55/3.5-5.6 IS.

More expensive lenses will have less distortion. The distortion is always greatest at the ends of the zoom range; if you find yourself taking lots of wideangle shots, you might want to invest in a dedicated ultrawideangle zoom. Alternatively, prime (non-zoom) lenses typically have much less distortion due to not having to make so many compromises. The most inexpensive option, of course, is to fix the issue in software.

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The first and third photos exhibit barrel distortion which is normally to be expected at 18mm when using an 18-55mm zoom lens. Software correction can help, but for best results you need software that includes a custom profile of that particular lens on that particular camera. There are also some perspective issues in shots #1 and 3, which are related to the camera position relative to the top and bottom of the cabinet.

The second photo demonstrates little, if any distortion. The reason the top of the cabinet appears wider than the bottom is one of perspective, and is due to your shooting position being closer to the top of the cabinet than to the bottom. This is further emphasized because the camera was tilted to the right enough that the right edge of the cabinet looks straight compared to the edge of the frame and the left edge of the cabinet appears tilted.

An extreme example of this effect would be a picture taken while standing between the rails of a train track. Even though the rails are a constant distance apart, they look closer and closer together the further away they are from the camera. If the image is composed so that one rail is "straight", the other rail looks very tilted.

Train tracks

enter image description here

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