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Lens
Tests
| EF 28mm f1.8 USM | EF 50mm f1.4 USM | EF 100mm f2.8 Macro USM |
| EF 180mm f3.5L Macro | EF 180mm f3.5L Macro + EF 1.4X II | EF 180mm f3.5L Macro + EF 2X II |
| EF 200mm f2.8L II | EF 200mm f2.8L II + EF 1.4X II | EF 200mm f2.8L II + EF 2X II | EF 200mm f2.8L II + EF 1.4X II+ EF 2X II |
| EF 300mm f4L IS | EF 300mm f4L IS + EF 1.4X II | EF 300mm f4L IS + EF 2X II | EF 300mm f4L IS + EF 1.4X II + EF 2X II |
| EF-S 18-55mm f3.5-5.6 | EF-S 10-22mm f3.5-4.5 USM | EF 17-40 f4L USM | EF 24-105mm f4L IS USM |
| Primes | 17mm Region | 24mm Region | 28mm Region | 35mm Region | 50mm Region | 100mm Region | 300mm Region | 400mm Region | 600mm Region |
| EF 180mm f3.5L Macro + TCs | EF 200mm f2.8L II + TCs | EF 300mm f4L IS USM + TCs | Tests With the Kenko TC | Macro Tests |
| Filter Effect on Sharpness and AF | Flare and Filters | Image Stabilizer Tests | TC Sharpness | Best of the Best | Method | Understanding the Results | Real World 100% Crops | Tripod Tests | L-Plate Test |
| As Shot | CA Corrected |
The EF-S 18-55mm f3.5-5.6 has high levels of chromatic aberration. So these measurements are presented As Shot and exactly the same exposure corrected for CA in Adobe RAW.
The CA correction applied was derived by quick visual examination of the corner and is shown in the below table.
| 18mm | 24mm | 35mm | 55mm | |||||
| R/C | B/Y | R/C | B/Y | R/C | B/Y | R/C | B/Y | |
| f3.5 | 0 | +37 | ||||||
| f4 | 0 | +34 | -9 | +15 | ||||
| f4.5 | -14 | 0 | ||||||
| f5.6 | -5 | +36 | -19 | +11 | -15 | +3 | -4 | +9 |
| f8 | -13 | +10 | -22 | +9 | -18 | 0 | -4 | +4 |
| f11 | -19 | +11 | -26 | +1 | -27 | 0 | -11 | -8 |
| f16 | -18 | +11 | -30 | -3 | -30 | -14 | -15 | -3 |
| f22 | -16 | +14 | -25 | -3 | -26 | -5 | -15 | -5 |
However the correction is not entirely successful due to the lens CA characteristic being seriously non-linear and uneven across the frame.
This can be seen for example by looking at the CA plane plots for 18mm f11.
First the As Shot case.
So after correction the corner CA is improved but significant CA is now introduced in other parts of the plane, in this case mostly on the blue channel.
Comparing the summary plots for f11.
Clearly these corrections could be optimized further, spreading the CA differently across the frame. However it will always be more imperfect than can be achieved with some other lenses that have better behaved CA. A good example is the EF 28mm f1.8 USM where the CA planes are ideally flat and linear allowing the ACR CA correction to work very well.
Last Updated 05/06/2008
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