The XF 23mm f/1.4 is an amazingly sharp lens. Straight from f/1.4, there is very good sharpness at the center and it remains at that level across almost the entire frame, with only a little further softening as you near the extreme image edges and corners. This is an incredible performance wide open. Stopped down just a bit, the 23mm becomes extremely sharp. At smaller apertures there is minimal difference between the center and the extreme corner, with very sharp results from corner to corner.
Having acceptable sharpness at any aperture frees the photographer to choose an aperture based solely on the desired depth of field, which is always welcome.
One of the best things about shooting with a fast moderate wide-angle is the ability to isolate your subject while also allowing for some context to the surroundings. As such, the quality of the out of focus areas is a main area of concentration for such a lens. If you’ve been shooting with many of the Fujinon XF lenses, you will notice that they all have a very nice, somewhat creamy bokeh signature, and that trend continues with the 23mm. While there can be some situations where some very faint rings can appear around specular highlights, typically those highlights are evenly illuminated and smooth. The XF 23mm f/1.4 turns in an excellent performance here.
Color, Contrast and Chromatic Aberration
The XF 23mm f/1.4 features a very similar color rendering to the other Fuji XF lenses. Fuji is relatively unique in that they seem to design their lenses to have very similar rendering characteristics, and this allows the photographer to change lenses and keep a similar look for all the lenses in their system. This lends consistency to a shoot and is one of the things I really appreciate when shooting the X-System. As such, the color response with the 23mm is excellent. It’s accurate and rich without being too saturated.
Contrast is great and gives the images some pop and clarity without going overboard by causing an image to appear harsh. The 23mm f/1.4 is somewhat unique in that the contrast is maintained even at maximum aperture. At f/1.4, the lens retains a high level of image contrast and clarity, giving your photos some punch at the widest apertures.
The one weak point with the 23mm f/1.4 is in longitudinal chromatic aberration, which shows up as green and red fringes behind and in front of the focus point on high contrast subjects. The longitudinal CA is somewhat pronounced at closer focus distances and in very high contrast situations. It’s not terrible, and I have seen far worse on many fast lenses, but it can crop up and become rather visible under the right circumstances. Some lateral CA is present, but generally minor, and can be easily corrected in post.
Distortion, Flare and Vignetting
The XF 23mm f/1.4 is very well corrected for distortion, and as such, it’s a great lens for moderate-wide shooting of architecture and other subjects with straight lines. You’ll notice in the image to the left that the lines are extremely straight. While this shot was corrected for perspective distortion in Lightroom (which is due to shooting up at the building, and is not a lens flaw), there was no correction for lens distortion with this image.
I was very pleased to see that the XF 23mm f/1.4 is also quite resistant to flare. As I mentioned on the previous page, the hood is large and provides good coverage, but I don’t think it needed to be that large simply because the 23mm does very well against bright light. Even with a point light source in the image frame, there is minimal effect on the final image. Even veiling flare is not a major issue with the 23mm.
The XF 23mm f/1.4 also has well controlled vignetting for such a fast lens. At f/1.4, there is minimal corner darkening that is only visible if you look for it really hard. Stopped down a bit it goes away completely.