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| Box and contents |
The Sony NEX-7 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 Carl Zeiss T* Sonnar E 24mm F/1.8 ZA lens was introduced in 2011, and has the distinction of being the first e-mount Carl Zeiss lens, and the first fast prime for the Sony NEX system. This relatively small lens, (about the size of the NEX 18-55mm kit lens) is build solidly, has a smooth manual focus action and a silent auto-focus motor which is great for keeping focusing noise out of movies. Due note this lens does not have OSS or built-in optical steady shot. Being a wide-angle lens, the benefits of image stabilization are not as pronounced as they are on a longer lens because the stabilization system doesn’t sense all that much movement with such a large area of coverage. Sony claims the lens has eight elements in seven groups, including two surface aspherical elements and one ‘ED’ element. This lens is marked made in Japan.
Fit and finish are very good. The lens appears to be clad in high quality plastic and metal, and has a metal mount, but it is very light-weight. It uses 49mm filters, just like the NEX 18-55mm and 16mm F/2.8 NEX lenses. The texture and black color perfectly match the NEX-7 body.
Focusing. This lens auto-focuses quickly, accurately, and without a peep. It’s much smoother and quieter than the SAM or slot-screw drive devices Sony uses on it’s Alpha system. The front filter ring doesn’t turn when focusing, so your polarizers and grads will work great. The focusing ring is easy to turn, and is damped about right.
The aperture blades form a nice circle at F/1.8, but at smaller apertures, the opening is oblong.
In the box is the lens, front and rear caps, softcase, plastic petal hood, and owner’s manual.
Requisite product shots.
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| Side shot |
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| Back side |
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| Sony X-ray view and MTF chart |
General information and specifications.
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Lens
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Box contents
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Front cap, rear cap, soft case, hood (ALC-SH114), and user’s manual.
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Cost
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Build quality
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Very good.
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Additional information
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Made for Sony NEX cameras, won’t work on A-mount cameras.
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Specifications below
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Optical configuration
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8 elements in 7 groups
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Angle of view
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61˚ Equivalent to about 36mm in full frame terms.
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Aperture
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7 blades, curved
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Full frame and APS-C
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Sony NEX only.
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Depth of field and focus scales?
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Nothing.
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Minimum focus, image plane to subject
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About 5.9″ (150mm)
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Minimum focus, end of lens barrel to subject
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About 2.6″ (66mm)
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Hard stop at infinity focus?
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No.
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Length changes when focusing?
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No.
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Focus ring turns in AF?
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No
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Filter size
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49mm.
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Filter ring rotates?
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No
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Distance encoder?
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Yes
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Max magnification
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1:4 or 0.25x
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Min. F/stop
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F/22
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Sony teleconverter compatible?
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No
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Length changes when zooming?
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N/A
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Dimensions WxL (my measurements)
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2.5″ x 2.6″ 63mm x 66mm.
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Maximum extended length (my measurements)
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2.6″ (66mm)
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Weight bare (my scale)
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7.8oz (220g) bare
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Optical qualities summary.
Lens flare/ghosting. Good control of ghosting. I see a streak of light at F/2.8, becoming strong at F/8 with the sun in the image, see examples below.
Light fall-off. Strong at F/1.8, but when ‘shading’ compensation is turned on, it’s very low. See samples below.
Color fringing (CA). Strong along the sides of the image, that’s below average for a lens of this quality, however, with CA compensation turned on, it’s not noticeable. It’s also removable in RAW. You see some axial color fringing too, but it clears up mostly by F/2.5.
Bokeh. Mostly harsh, although you won’t be getting much background blur with this lens. See examples below.
Color. Seems about the same as other Sony lenses.
Close up filter. Used +4, doesn’t offer better quality.
Coma. A small amount at F/1.8, basically gone at F/2.5, see samples below.
Regular filters cause no additional light fall-off.
Filter size. 49mm. Sony lenses that use 49mm filters; NEX 16mm F/2.8, NEX 18-55 F/3.5-5.6, 30mm F/2.8 macro, 50mm F/1.8 SAM and 28mm F/2.8.
Distortion. Minor pincushion, although mostly correctable with simple distortion sliders. In-camera distortion compensation takes care of this.
Distortion example directly below.
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| Minor pincushion distortion, standard image, no correction |
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| No distortion compensation |
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| With distortion compensation |
Distortion is not really a problem with this lens, but if you look closely you’ll see minor pincushion distortion with a slightly complex curve, although it’s straightens out well in post processing. If you turn on distortion compensation in your NEX camera, it corrects this automatically. The top image is the standard distortion subject; I used the bottom two for the camera distortion compensation comparison.
Bokeh samples.
Bokeh looks harsh at all apertures, but it’s hard to get any background blur unless focusing on something close. These crops show bokeh at a distance of about 35′ (10m) when focused at 6-8′ (2.5m).
Sample of close-focus bokeh
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| Crop from center of image |
Bokeh looks smoother if you focus on a close subject as I’ve done here. This is a crop from the center of the image at F/1.8.
Light fall-off samples with no ‘shading’ compensation.
There is heavy light fall-off at F/1.8, but it diminishes greatly at F/2.8. If you have ‘shading’ compensation enabled in your camera, you won’t see this.
Light fall-off samples with ‘shading’ enabled
This is what you’ll see it you have ‘shading’ set to ‘auto’ in your camera.
Flare and Ghosting
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Red blob, F/2
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Streak, F/2.8
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Streak, F/4
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Streak, F/5.6
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Ghosting control is pretty good at aperture settings smaller than F/2. About the only thing I see is a magenta blob. When the sun (or very bright light) is in the image, there seems to be an unusual light streak from the aperture opening from F/2.8 and smaller, becoming more noticeable as you stop down. I see some flare in the bottom center-right in the F/5.6-8 shots.
Let’s check out the close-focus capabilities of this lens.
The sample shot was taken with the Sony NEX-7 24MP camera, so don’t compare it with all others that were taken with 12-16mp sensor cameras. The subject is a standard US stamp, 0.87″x 1.0″ or 22mm x 25mm. Also, note the macro shot was taken as close to the subject as focusing allowed; in this case a very short 2.6″ (66mm), measured from the front of the lens barrel to the subject.
This lens has a reproduction size of 1:4, which is one quarter life size. I see a very impressive stamp shot, showing tremendous detail, and a total lack of any color fringing, that’s great! The shot below was taken at F/5.6, but F/4 was almost as good. As a side note; the “1996” on the bottom left of the stamp measures a mere 1mm wide.
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| As close as you can get, F/5.6. |
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F/5.6, RAW, no adjustments
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F/5.6 Jpeg with compensation
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This crop is from the last 340 pixels on the middle right side. I see strong magenta color fringing (and a little cyan) along the house and wall, but if you use CA compensation in your camera, it’s nearly eliminated.
Coma shows up as weird looking, smeared blobs at points of light in the corners of the image, especially in super wide angle lenses. Coma in not a problem with this lens, although there is a small amount at F/1.8, clearing up at F/2.5. 100% crops from the far corner.
Conclusion.
The Sony CZ NEX 24mm F/1.8 lens produces outstanding results throughout the entire frame, which is not typical for a wide angle lens; in fact, it shows the best results of any wide angle lens I’ve tested yet, and that includes full frame lenses like the CZ 24/2 and 35/1.4 G! Most wide angle lenses are mushy in the corners unless stopped down hard, but the NEX CZ 24/1.8 is actually quite sharp at F/1.8 in the corners! This lens is optically at its best between F/2.8-4, stopping down additionally is not necessary for sharper shots. A tid-bit that will make some people mad: I’m glad I don’t have the Sony 35/1.4 G lens anymore, if I would’ve compared the Sony 35mm F/1.4 G using the A900, and the NEX CZ 24mm F/1.8 using the NEX-7 at apertures of F/1.8-4, the 35mm F/1.4 G would literally look like it was focused improperly, there would be that much difference at those apertures! Both cover the same area and have the same megapixels, so it’s a fair comparison.
There are a couple of small negatives; I see what appears to be an odd aperture induced light streak when very bright lights are inside the image, like the sun, and that may affect your sunset type shots, but if you’re not in to that, keeping the sun out of the image basically eliminates this issue. The other slight negative would be the high cost, it does perform extremely well overall, but so does the Sony 35/1.8 SAM, and that costs about 1/5 the price of the CZ 24mm F/1.8. A true wide-angle (36mm equiv) fast lens is harder to make, and I’m sure it costs more to make, (plus the metal mount and a silent AF motor), but $1099 seems steep for a very small and light-weight lens! So is it worth it? If 36mm (FF equiv) is your focal length, of course it is.
This lens will appeal to those that enjoy photographing street scenes in low-light without a tripod, and want something small and light-weight. The NEX-7 and CZ 24/1.8 lens will fit in a jacket/coat pocket, but not your pants pocket unless you’re really big!
Believe it or not; I’d prefer this combo (NEX-7 and 24/1.8) to the A900 with either the CZ 24/2 or 35/1.4 even if they both cost the same, why? The NEX-7 and CZ 24/1.8 performs better than the A900 with either of the two lenses mentioned. Plus, I don’t like the bulk and weight of the full frame equipment, I enjoy traveling light, even if it’s just across town.
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