Compared to the AF 50mm f/1.8
- Date of 1st production: April 1995
- Focal length: 50 mm (75mm equivalent in 35 mm on DX sensor)
- Angle of view: 45º (22º50' in DX)
- Maximum aperture: f/1.4
- Minimum aperture: f/16
- Construction: 7 elements/6 groups. Has SIC coating.
- Diaphragm: 7 straight blades
- Minimum focusing distance: 0,45m
- Maximum magnification: 1:6.8
- Weight: 230 g
- Dimensions: 42.5mm x 64.5mm
- Diameter of filter: 52mm
- f/1.4 – f/1.8: Sharp but due to very shallow DOF focusing becomes very critical. Place subject in center since sharpness is limited to the center of frame. Contrast may be low but fixable.
- f/1.8 – f/2.5: Results are much better with sharpness covering a larger part of the frame and a good boost in contrast. This is my preferred range since I like the amount of DOF here and the bokeh.
- f/2.5 – f/4: the best performance is in this range but the DOF is starting to affect the background.
- f/4 – f/11: Very good, but the cheaper AF 50mm f/1.8 lens performs better.
- f/11-f/16: Best avoided due to diffraction
Thankfully the optical construction of the AF 50mm f/1.4 lens was designed such that the CA’s are at their least near wide open. This is another reason why from f/4 onwards the cheaper lens performs better. In some cases blue fringing at high contrast transitions are visible but in most cases this is not a problem. The D300 and D3 combined with Capture NX help to remove most traces automatically.
There is some light fall off around the edges of the frame that is quite noticeable on the FX format up until f/4. On the DX format its noticeable up until about f/2 and gone by f/2.8.
No distortion is noticeable unless you shoot a brick wall. In such a case, some minor barrel distortion is visible but nothing to worry about.
The color rendition of this lens is neutral to cool, with a greenish tinge.
Apart from the speed and the isolation capability, this lens can provide very nice bokeh from wide open to about f/2.2 even though the lens only has seven aperture blades that aren’t even rounded though they do provide a strange curved “smoothness” up until f/2.5. From then onwards, the bokeh can be described as being a little bit harsher though still quite good, but this depends a lot on factors such as subject, lighting and distance. High lights in the OOF areas can show the 7 diaphragm blades instead of a circle especially after f/2.8 when the blades are more sharply pronounced (see below). Once you get to know the lens, you may find yourself trying to avoid spectral highlights in the OOF areas of the frame. Generally speaking the bokeh and the smooth gradual rendering of the OOF fields are very good up until f/2.5.
Flare and ghosting can be a problem with this lens if you are not careful, but generally, this lens does OK. It does flare, so generally you will want to try and avoid pointing the lens towards the sun and other strong light sources. In these situations remove any filters you may have attached since a filter will only add to the problem and make sure your front element is squeaky clean. I also recommend the HR-2 hood or a rubber hood to help in the flare department and would recommend against the use of filters if possible.
There is some coma wide open but from f/2.8 onwards, spots of light are rendered round.