Full review of the Sony NEX 10-18mm F/4 OSS     Box and contents     The Sony NEX-C3 was used for this review.    For a better understanding of terms and methods used in this review, go here.   The usual center, mid-section and corner crops are located at the very bottom of the page.     Introduction.   The Sony NEX 10-18mm F/4 (Made in China, Fabriqué en Chine) is a very compact and light-weight constant aperture ultra-wide angle zoom lens specifically designed for Sony's APS-C mirrorless camera system.  Many ultra-wide zoom lenses have a built-in permanent hood, no stabilization, and no way to use filters; thankfully, this lens does incorporate those features.  Sony packed this lens with OSS or Optical SteadyShot, 62mm filter threads, a very quiet focusing motor for video nuts, and threw in a petal type hood for good measure.  Also included are three aspheric elements and one 'ED' element in the design.    Fit and finish are quite good.  The lens is clad in high quality plastic, including the filter threads, (so be careful), but has a metal mount for added durability.  Focus and zoom rings have a very tight ribbed design, and are not rubberized, so they won't turn chalky over time like the full frame and 'DT' lenses.   The zoom action is smooth and damped properly in my opinion, (one finger zooming is possible) and holds its position well, so there is no zoom creep during normal use; which is good as there is no zoom lock.  There is a single plastic extension barrel that protrudes a maximum of 10mm at the 10mm zoom length, and is fully seated at 18mm.  Focal length index marks come at 10mm, 12mm, 14mm, 16mm, and 18mm.  The EXIF date matches those lengths.     In the box: the lens in bubble wrap, front and rear caps, a petal type plastic hood, and owner's manual.     Focusing.  This lens auto-focuses almost silently.  Focusing seems quite accurate at all focal lengths, and reasonably quick in good light, however, your mileage may vary depending on camera model.           Requisite product shots. Front, fully extended Back Sony MTF graph and X-ray view       General information and specifications.   Lens Sony NEX 10-18mm F/4 OSS   Model number SEL1018 Box contents Front and rear caps, hood, and a user's manual.  Cost $848 retail as of 2/2013. Build quality Good to very good. Additional information First ultra-wide zoom for the NEX system. Specifications   Optical configuration 10 elements in 8 groups Angle of view 109°-76°  Aperture 7 blades, curved Formats NEX E-mount only.  With a crop factor of 1.5x the coverage equals 15-27mm in 135 film format. Depth of field and focus scales? Nothing. Min. focus distance, image plane to subject @ max reproduction ratio About 8.7"  (221mm) Min. focus distance, end of lens barrel to subject @ max. reproduction ratio About 5.2"  (132mm) Hard stop at infinity focus? No Length changes when focusing? No Focus ring turns in AF? No Filter size 62mm. Filter ring rotates? No Distance encoder? Yes   Max magnification 0.1x, or 0.15x (1:6.6) with crop factor. Min. F/stop F/22 Factory teleconverter compatible? N/A Length changes when zooming? Yes Dimensions WxL  (my measurements) 2.75" x 2.5"   70mm x 63mm.  Extends another 10mm at the 10mm zoom setting. Maximum  extended length (my measurements) 2.9"  (73mm)                               Weight bare (my scale) 7.9oz  (225g)      Optical qualities summary.   Lens flare/ghosting.  Some small to medium green colored blobs appear when super bright light sources are close to, or inside the frame, samples below. Color fringing (CA).  Very good control at the long end, average control at the short end. You'll see some magenta and cyan at high contrast edges along the sides of the image.        Bokeh.  Can be a little 'busy' at all focal lengths depending on focusing distance, but getting any background blur is tough at these super short focal lengths.   Color.   Neutral.    Close up filter.  N/A.      Coma.  None that matters.   Regular filters:  No issues at any focal length.   Filter size:.  62mm.  Other NEX lenses using this size are: Sony 18-200mm LE, and Tamron 18-200mm.   Distortion.  Low at all focal lengths, but 'wavy' and hard to correct from 10-14mm.  Check out the cropped samples below.   10mm, uncorrected RAW, moderate wavy distortion 12mm, uncorrected from RAW file, mild wavy distortion 14mm, uncorrected RAW, mild pincushion distortion. 16mm, uncorrected from RAW file, mild pincushion distortion. 18mm, uncorrected RAW, moderate pincushion distortion.   Distortion is strong and wavy in uncorrected images like RAW at 10mm, but zooming out slightly corrects much of that.  From 14-18mm there is some pincushion, but is mostly correctable with standard distortion sliders.  I have no idea how well the jpegs get corrected in-camera; due to operator negligence, there aren't any corrected crops to show.     Light fall-off.              10mm F/4              10mm F/5.6            18mm F/4              18mm F/5.6   Light fall-off is mild to moderate at all focal lengths when the aperture is wide open.  Stopping down is not really needed.   No problems with standard width filters at F/4.      Flare and ghosting.              18mm F/5.6 green with orange dot              14mm F/5.6 green blob by sun   The Sony NEX 10-18mm F/4 OSS lens controls ghosting well, although there is a green blob to be seen when super bright lights are in the scene.  Contrast holds up well even with the sun blazing in the lens, especially at the ultra wide end.     Bokeh samples.              10mm F/4              10mm F/5.6            18mm F/4              18mm F/5.6   Bokeh looks pretty smooth at the ultra wide end when you focus on something about a foot away, (.3m), it's rather harsh at longer distances, and similar to the 18mm crops.  Background blur is hard to get with these short focal lengths.  Bokeh is the character of out of focus highlights, and not simply how far out of focus the background is.       Let's check out the close focus capabilities of this lens. Check out the 100% cropped portion of the full image.  The sample shot was taken with the Sony NEX-C3 16mp camera, so don't compare it to others that were taken with 12 or 24mp cameras.  The subject is a standard US stamp, 0.87"x 1.0" or 22mm x 25mm.  Also, note the shot was taken as close to the subject as focusing allowed; in this case a very short 5.2" (132mm), measured from the front of the lens barrel to the subject.     This lens has a small reproduction size of 0.1x, (0.15x or 1:6.6) in 135 film format, and it produced a sharp, but small close focus shot at F/8.  As a side note; the "1996" on the bottom left of the stamp measures a mere 1mm wide.   As close as you can get. F/8. No larger image     Conclusion.   The Sony NEX 10-18mm F/4 OSS is an extremely wide zoom lens with the same coverage as a full frame 15-27mm lens, and is the first ultra-wide zoom for Sony APS-C lovers since the introduction of the less than stellar Konica Minolta (and later Sony---but made by Tamron) 11-18mm F/4.5-5.6.  Fortunately, the new NEX 10-18mm lens is worlds better all the way around than the almost decade-old Tamron.  Earth to Sony; time for a new 'DT' ultra-wide zoom!   One of the pluses of the Sony NEX 10-18mm F/4 is the constant semi-fast aperture throughout the focal range, meaning you can set it at F/4 at all zoom lengths.  Other lenses like the variable aperture Tamron mentioned above reduces the aperture as you zoom out, and also reduces the light gathering power of the lens.  Although F/4 is not really considered fast, it will allow you to shoot at a lower ISO in low-light hand held conditions, and don't forget the OSS, which helps minimize the effects of hand shake, allowing you to shoot at an even slower shutter speed.   Resolution wise, the lens is slightly soft at F/4, but totally usable in low light.  Fortunately, the sides at F/4 are not mushy, and contain a lot of detail.  Stopping down to F/5.6 results in a very nice sharpness boost across most of the frame, although towards the long end you might need F/8 for the very best extreme sides and corners.   There are no real negatives to speak of unless you want to nit-pick at things like the wavy distortion at 10-11mm, and the slightly soft performance at F/4, but again, those aren't deal breakers for NEX lovers.   Bottom line: I would consider this lens excellent at F/5.6-8.  Even thought I reviewed it on a 16mp camera, I'm quite certain it will support much more than that, making it a good long term purchase.      Highly recommended for Landscape (all focal lengths), Architecture (14-18mm), and Real Estate photography (14-18mm) at F/5.6-8.

Sample crops from the centers, mid-sections and corners.   10mm.               Center           Mid-section              Corner F/4 F/5.6 F/8   14mm.               Center           Mid-section              Corner F/4 F/5.6 F/8   18mm.               Center           Mid-section              Corner F/4 F/5.6 F/8   At 10mm, the centers are very sharp at F/4, with the mid-sections and corners sharpening up a stop down.  As you zoom towards the longer end, there is a nice resolution jump across the whole frame at F/5.6, with the corners at 18mm maxed at F/8.  As you stop down to F/8, diffraction is slightly noticeable in the centers, and the whole image becomes soft at F/11 and smaller.     All focusing distances were at or near infinity using manual focus and focus bracketing.  Exposure differences are due to light fall-off.   That's it for the review, if you'd like to help out the site, please visit B&H Photo if you're thinking of purchasing the Sony NEX 10-18mm F/4 OSS, thanks!