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Lens Tests

Purpose

Review the quality of various E-mount (Sony) lenses, using the Nex-6, at various aperture settings.

Testing should ideally be directly comparing against similar lenses, using the same framing, and on a tripod and timer to reduce the chance of vibration.  The main variable between my test shots was needing to adjust focus in cases where the focus seemed to latch onto a close fencepost.  While I attempted to use DMF in some cases, I had to throw out some results as they may have been misfocused.  I re-ran the tests again on a separate day to get a second set of data points.  (Getting a solid test is harder than it might first seem.)

Settings

The below 100% cropped samples were all captured using the camera's Fine JPEG mode, and re-saved in my photo editor with some reduced quality, as happens with JPEG.  Settings were 0 sharpness, Vivid, with -1 saturation.  (This is my standard setting, which allows for a slight punch of color, without being overbearing.)  ISO was fixed to 100, and the shutter allowed to change to accommodate the changing lighting (clouds).  Crops were taken slightly left of the center of the frame.  The first day's photos used +.3EV to get a bit more detail out of the images.  On the second set of comparisons, I tried +0EV and a slightly different location.

Test Links

20mm tests

30mm tests

50mm tests

18-105mm lens tests

Test chart #1

Test Chart #2

(To be continued....)

Conclusions

SEL20F28

It appears to me that the performance is superior to the 18-55, although the difference is subtle enough that I would not blame anyone from just continuing to use the 18-55.  It seems worthwhile to me to use it over the 16-50, or any time you want a compact lens option.  It is generally believed that this lens has higher image quality than the 16mm lens.

SEL16F28

The below conclusion is modified from my earlier test of the 16mm lens, although based on my recent tests, I would also add that you might want to stop down the aperture a bit for good results.

The 16mm lens is not without it's quirks, but overall, sharpness is great.  CA and PF are a concern, and it would be recommended to use software correction when it becomes objectionable.  The lens is perfectly usable at wider apertures as long as soft corners can be tolerated; on my copy, the severe softness in the corners disappears by f7.1.

At such a low price-point, the 16mm turns the Nex into a truly compact camera, capable of excellent wide-angle photos, provided that you can live with some quirks.

The 16-50 and 18-55 Kit Lenses

I think the bottom-line with these lenses is that they will do better at f5.6 and greater, in general, as with many consumer, budget-oriented lenses.  Results are going to be good enough for most casual use.  While the 16-50 can be preferred simply for the convenience of a small lens,  it competes well with the 18-55. In some cases one or the other appears better, but much of the time they are similar; it could well be that differences in my tests come down to minor focus differences.  Not really shown in these examples is that the bokeh of the 18-55 is generally better than that of the 16-50, although for some this will be an esoteric detail.

Last updated: June 9, 2014.