Designed in the early 60's, my
copy of the Nikkor-N 24mm f/2.8 was made some time between 1975-1977.
This is not a lens with a legendary reputation, but my copy was $45.
The "K" version of this lens (what I have) does have seven aperture
blades, which is nice for sun stars. The earlier version was identical
opticaly but only had six aperture blades.
Visibility on this day is well
over twenty
miles. Shot on a tripod, shutter speeds fast enough to eliminate any
kind of shake. Manually focused on the barn just off center, at maximum
aperture and focus left there, no adjustments made for
focus shift or field curvature. White balance set to daylight.
Overall field of view, the Lens Turbo II is of course cropped a little
bit, but it also shows less vignetting.
In the center the Lens Turbo II gives this old lens a solid boost in
sharpness.
In the extreme corner things switch, it's much better on the A7 than
with the Lens Turbo II on the A6000.
Rather than slog through
f/4 and f/5.6 I'll jump to f/8 where this lens
is probably going to be used. The lens comes to life on the Sony A7.
Corners are not incredible on the either combination yet are still
superior on the A7.
24mm is a classic landscape focal length, so let's take a look at f/11.
In the extreme corner the Nikkor-N 24mm f/2.8 get ok at f/11, but just ok, nothing to write home about.
As these focal reducers have a poor reputation for working with wide
lenses, here the Lens Turbo II highlights the imperfections of Nikon's old 24mm f/2.8 lens.