- The camera was not mounted on a tripod (though the shutter speeds are fast enough )
- Automatic, not manual focus (so any front /back focus of the lens is not correct )
- ISO 400 (to have good time ) and not 100
- I used aperture priority and not M
- The plan of focus is probably not far enough to bring down the whole scene to infinity , any " softness " in the crop of the edges may be due to differences of the PDC.
RAW pictures have been processed with Digital Photo Professional 3.9.2, and we applied to all photos identical fixes about vignetting, distortion, chromatic aberration. We also applied a sharpening of 3 to pump up a little of detail and to better observe the differences. The other parameters are identical (contrast 0 , saturation 0 , neutral style , WB , etc.).
In general, corrections are needed especially for the 17-40 that suffer particularly from falls of light at the edges and of greater chromatic aberration, but these are easily correctable defects with no loss of photo quality, I decided to avoid everything that is not concerning the rendering of detail and contrast.
Let’s remember that obviously @ iso 400 vignetting corrections introduce some noise in the areas around the edges, but it is perceptible only at 100% magnification . Also the light conditions in which the shots were made were probably not the best, as you will see from the picture as a whole, given the time, but the clouds allowed a diffuse light and quite decent EV range that was ok for shooting.
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| 16-35 @ 16mm |
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| 17-40 @ 17mm |
On all the shots we see a consistent trend of the exposure to work better with the 16-35 or at least to make an image brighter there compared to 17-40 in shots that are as mentioned were performed in Av; probably in M, with the same values/aperture, we would see similarly exposed images. Something changed nevertheless at level of exposure metering with each lens.
I made the shots with both lenses at maximum width (17mm and 16mm ) and then 20mm and 35 mm. By Photozone tests a big loss of detail in the 17-40 is noticed, @ 17mm and especially at maximum aperture, much less @ 20mm. However, from my tests so you do not notice appreciable differences. So we initially present only the test @ 17/16mm and 35mm, probably the most used focal lengths on the field if you buy such a wide angle. The tested apertures are f4 (and 2.8 for the 16-35 ), f5.6 and 6.3.
100 % crop and 900x600px , click on the image to open in full size.
The central focus is always on the lamppost .
Super- wide-angle focal length ( 16/17mm ) f 4 (and only for the 16-35 f2.8 )
Super- wide-angle focal length ( 16/17mm ) f 4 (and only for the 16-35 f2.8 )
CENTRE
Comments: different exposure apart, there is a little more of details with the 16-35 and certainly more contrast. At 2.8 you do not notice appreciable differences, I would say that 2.8 with the 16-35 have at least the same quality of 17-40’s f4. It 's definitely a good thing for a lens whose difference (including the price) is justified especially for that +1 stop of light.
SIDE
Comments: beyond the different exposure I would say that differences are subtle, just a bit softer at 2.8 but negligible (at the edge the PDC is an issue). Still a positive vote for the 16-35 @ f2.8 aperture.
CORNER
CENTRE
Comments: different exposure apart, I would say that differences are barely perceptible, certainly a better quality of the 16-35 about micro-contrast, but perhaps also due to better luminosity.
SIDE
Comments: here I was surprised that there is a better micro-contrast by the 17-40 what initially made me think about flaws in the 16-35’s test, such as a slight shake-or a non-precise focusing. Note that the right side of the image is located in front of the plane of focus, but at the same aperture and focal length you should not expect perceptible difference between the two lenses. The 17-40 actually worked in 21mm not 20, but it does not make much difference.
CORNER
Comments: different exposure apart, even here you can see some margin in favour of the 17-40. Notwithstanding the concerns outlined above, remember that this is an area slightly in front of the plane of focus.
Super-wide-angle focal length (16/17mm) @ F6.3
CENTRE
Comment: as with f/5.6 there is a slight advantage for the 16-35, certainly amplified by the better exposure.
SIDE
Comments: as in F/5.6 there is a slight advantage of the 17-40 about micro-contrast
CORNER
CENTRE
Comments: definitely a winning for the 16-35 @ f/2.8, which behaves like the 17-40 @ f/4
SIDE
Comments: as expected, certainly better than the 16-35 by losing less detail, and f/2.8 is virtually identical to the 17-40’s f/4, maybe just a tad softer
ANGOLO
Comments: slightly more details with 16-35.
SIDE
Focal moderate wide-angle (35mm) to 6.3 f
CENTRE
Comments: again, on the corner, the 16-35 seems to be slightly softer than the 17-40.
I have limited test up to to F6.3 wanting to stress the lenses in the conditions where they usually make less, especially useful if you use them in low light situations. If used for landscaping with a tripod, narrow apertures should iron out all the differences. However, given the lower detail of the canon ef 16-35 at the edges I run tests with this lens @ f/8 too, here we present the differences with respect to the F/6.3 in the corner. Note that light had changed in the meantime both temperature and intensity (there is also a +2/3 EV @ f8), hence the more blue hue in the shots at f/8.Canon ef 16-35 2.8 L @ 35mm – f8 vs f6.3 – SIDE
Comments: Despite the shutter speed could be so low at the limit of the hand-shake, we note a slight improvement at f8, which probably it is just a higher PDC (the crop is right in front of the focal plane)
Canon ef 16-35 2.8 L @ 35mm – f8 vs f6.3 – CORNER
Comments: Despite the shutter speed near the limits of an hand-shake, there is a little ' improvement at f8, but probably it is just a higher PDC ( the crop is in the lower right front of the focal plane )
Conclusions: Beyond the typical defects of 17-40 such as vignetting, chromatic aberrations, etc (but it still makes it well in other situations, such as backlit ) that are easily correctable as long as you shots in RAW , there was no substantial difference between the two lenses at the level of detail and contrast. The 16-35 is a bit more sharp in the centre, a difference that is lost from up to F6.3 (but have not tried narrower apertures on both lenses). The 16-35 obviously has the advantage of a stop more light and has an image quality @ f/2.8 almost equal to f/4, thus for sure it is a usable aperture .16mm against 17mm may sound silly but just look at the full pictures at the beginning to realize that the field of view is noticeably wider at 16mm. If all these aspects are enough to justify a double cost compared to 17-40 (1200 versus € 600 ) is up to to the pockets of each of us. Personally, I abandoned the idea of doing the upgrade.
©2010 Marco Palladino
