Nikon's recently announced 50mm F1.4 is an interesting lens because its retail price is $496, $130 less than the slower 50mm F1.8 S model. Generally, that relationship is flipped: faster lenses cost more money.

Indeed, that was the case in Nikon's DSLR lineup. The AF-S F1.4G was the premium option at $439, while the F1.8 was $219. Adjusted for inflation from their respective 2008 and 2011 launch dates, the previous generation was priced at $643 for the F1.4 and $307 for the F1.8.

In theory, the new F1.4 lens trades quite a bit of sharpness for 'character,' letting it achieve its lower price point. But this raises an interesting question: given the last 16 years of improvements to manufacturing and engineering, will the new budget option outperform the older premium model?

We aimed to test this, attaching the 50mm F1.4 G to a Z8 using Nikon's official F to Z adapter. We took the same shots with both lenses to see how the new entry-level stands up to the older pro-level lens. We haven't applied distortion correction to the images from either, though we have used the built-in profiles and CA correction.

Sharpness and vignetting

Nikkor Z 50mm F1.4	F1.4	F1.8	F2.8	F5.6	F8.0
Nikkor G 50mm F1.4	F1.4	F1.8	F2.8	F5.6	F8.0

The Z-mount lens is quite a bit sharper in the center and corners when wide open, a trend that continues until around F2.8, where the G lens sharpens up substantially in the center. Even at F5.6, though, the older lens is still a touch softer in the corners, though the two lenses are relatively comparable at F8.

Both lenses have a fair amount of vignetting, though the G model's clears up a tad faster.

Bokeh

Nikkor Z 50mm F1.4	Nikkor G 50mm F1.4

To our eyes, the Z lens has more pleasing bokeh, thanks to less mechanical vignetting. That means it'll render out-of-focus points of light as circles, rather than ovals across much more of the frame. The G model can produce circular bokeh in the center, but they turn to cats eye pretty quickly as you move toward the edges of the frame.

Our one concern is that the newer lens' bokeh does seem to have slightly brighter edges, which could result in some busy-looking backgrounds if you're shooting in front of things like receding foliage.

Infinity Focus

Nikkor Z 50mm F1.4	Nikkor G 50mm F1.4

At infinity focus, both lenses have a very similar field of view. That's not necessarily a given, as evidenced by...

Close Focus

...the fact that there's a pronounced difference in focal lengths when shooting a close-up object near the lens' minimum focusing distance. The Z model has a substantially wider field of view with the G exhibit much more 'breathing.'

Nikkor Z 50mm F1.4	Nikkor G 50mm F1.4

It's also worth noting that the newer Z model can focus closer than the older lens. The rollover below shows the lenses at their minimum focusing distance.

Nikkor Z 50mm F1.4	Nikkor G 50mm F1.4

While this is far from a full lens review, it's hard not to look at the comparisons here and conclude that Nikon's budget lens has caught up to and surpassed its old high-end option. The Z model is sharper and has faster, more accurate, and closer focusing capabilities.

This isn't to say that the Z 50mm F1.4 is a perfect lens. It's heavier and larger than the 50mm F1.4 G, and its sharpness, vignetting, and chromatic aberration performance could be better by modern standards. The great thing about Nikon's modern lens lineup, though, is that if want a sharper lens, you can have it: the 50mm F1.8 S performs ridiculously well in that regard. The baseline has been raised up to where professional lenses used to be, and today's pro models would've almost seemed like magic just a decade and a half ago.