HD vs. SMC Pentax FA Limited Lenses
Chromatic Aberration
Chromatic aberration is mainly influenced by the lens design itself, but coatings can also have an impact. Because of this, we take a look specifically at CA.
For this test we used a well-lit, sharp transition from dark to bright, in order to make manifest any chromatic aberration present in the image.
We typically look at three parts of the image: the focus point in the center, the top and the bottom (beyond and before the focus point). Since we know from previous experience that there is no CA manifesting in the center, in the present test we only look at the top and bottom parts of the image.
You can click on the files to see 100% crops, and navigate by using the left-right arrows. We present results separately for each lens and each section of the frame.
31mm F1.8
Top
SMC 31mm | HD 31mm | |
| F1.8 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
Bottom
SMC 31mm | HD 31mm | |
| F1.8 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
There is no difference whatsoever between the results with the SMC and HD lenses.
43mm F1.9
Top
SMC 43mm | HD 43mm | |
| F1.9 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
Bottom
SMC 43mm | HD 43mm | |
| F1.9 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
As with the 31mm, the 43mm shows no difference at all between the two versions.
77mm F1.8
Top
SMC 77mm | HD 77mm | |
| F1.8 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
Bottom
SMC 77mm | HD 77mm | |
| F1.8 |  |  |
| F2 |  |  |
| F2.8 |  |  |
| F4 |  |  |
| F5.6 |  |  |
| F8 |  |  |
| F11 |  |  |
| F16 |  |  |
| F22 |  |  |
The 77mm follows the same trend and shows no difference between the SMC and HD versions.
Verdict
The changes brought by the HD FA Limited have no impact on chromatic aberration. This is not overly surprising because CA is mostly influenced by the lens design itself. Still, coatings could have had an impact because they influence light transmission. It is not the case here.
