The Nikon 28-80mm f3.3-5.6 G lens is by many considered to be a very sharp lens, especially for its low price. I've reviewed the Zykkor 28mm f2.8 earlier and think it would be interesting to compare it with the Nikon which is a little more commonly known for it's performance then the Zykkor.
The lenses are very different. The Zykkor is a metalbody lens with manual focus. The Nikon is all plastic (except for the glasses of course) with no manual aperture at all. It needs to be controlled from the camera. The Zykkor can be used as a point and shoot if you shoot at a distance with focus to infinity. The Nikon's autofocus is extremely quick! So you can use it in a lot more different situations.
The Nikon is also a Zoom lens, giving you a much broader range of applications than the Zykkor. So, is there any use for the Zykkor at all? Well... let's find out. ;-)
Iv'e done a side by side comparisment on the two lenses at 28mm. Overall it seems that the camera (Nikon D700) exposes the Zykkor a bit more then the Nikon. All the Nikon samples are slightly darker than the Zykkor samples.
At f2.8 (Zykkor) and f3.3 (Nikon) the fall off is the worst. They quickly recover at f4 and on.
As we can see here, the falloff on the Nikon is horrible at f3.3! It's almost you may think this is a DX lens.
The Zykkor at f2.8 has a clearly visible falloff in the corners, but nowhere as heavy as the Nikon. Both lenses get better at higher f numbers.
Both lenses are pretty sharp! Many consider the Nikon to be very sharp but there is not much to be found about the Zykkor. (This is why I am writing this, if you haven't guessed.) ;-)
The Nikon appears to be a bit on the soft side at a first glance.
Overall, this looks a bit sharper than the Nikon to me.
The Zykkor is pretty sharp at wide open aperture. The Nikon doesn't go to f2.8, so I used the closest which is at f3.3. The Nikon is awefull at that aperture. Not only is it considerable softer than the Zykkor, but it also throws in a nasty purple shade. The Zykkor wins this one hands down.
The Zykkor gets even sharper here. The Nikon looses it's purple haze and gets sharper, but again the Zykkor has the edge here.
Now the two lenses appear to be almost identical, but the Zykkor still has a slight edge here.
The same as with f5.6. It seems that both lenses are getting slightly better at this aperture, but still the Zykkor has the edge.
Here there is no difference that I am able to spot. They seem identical at this aperture.
Now the Zykkor seriously starts to soften up, and for the first time the Nikon has a sharper image.
All i all the Zykkor leaves a better impression at 28mm than the Nikon. The disadvantages are of course that the Zykkor is fixed lens (if you plan to "walkabout"), so the Nikon is much more flexible at that. The Zykkor is also much heavier than the Nikon and it has no autofocus.
I'd use the Zykkor if I have a certain clue of what I am going to look for in a photograph. The Nikon is a much better companion if you are on a trip and the pictures you take are much more spontaneous and out of the blue. The fact that the Nikon is inexpensive and very light adds to this.
The fact that the Zykkor works so well at low-light also makes it a better choice where light is low and the action is high. ;-)
I hope you enjoyed this little comparisment and found something usefull in it.