24mm, f2.8 sharp?

<p>Steven - If you have broken the mount off of your lens, chances are you have broken something else inside. Its not the mount breaking that people are worried about, its the fact that the lens is not made very well.</p>

<p>Right, the primary concern is not literally the plastic mount breaking; it is the overall construction quality of those plastic mount lenses. The first time I heard (or actually read about) Nikon using adhesive tapes inside those lenses, my reaction was exactly the same as Arthur Yao's.</p>

<p>Incidentally, it may seem to be easy to put a new mount onto the lens, but it has to be on exactly right. If you over-tighten one side too much, you may tilt the lens by just a tiny bit, and when the lens is not exactly perpendicular to the sensor plane, your focusing can be off a bit so that one side of your image will be sharper than the other side. I am not sure everybody has the right tools to do that kind of precision jobs.<br>

That is partly why I prefer a new lens from the factory than one that is repaired.</p>

<p>A number of Nikkor lenses have play in the mounting of the inner and outer parts (i.e. the one which holds the elements and the outer part) so if you turn the camera to a different orientation, the image projected by the lens shifts laterally. Basically there is no guarantee of perpendicularity of the optical axis and the sensor with these lenses.</p>

<p>It's curious / interesting how widely the opinions differ on the 20mm and 24mm Nikkors.</p>

<p>I've no complaints with my AIS version of the 24 mm., f/2.8. I think the problem you might be having is with focus. The D300 has a dinky little finder and is really set up for autofocus. I use mine on an old F2 , F3, or Nikkormat. Compared to the focusing screen on the D300, these things are huge, bright and easy to focus.</p>

<p>Chris, if you're a nut for sharpness, you need to avoid the small apertures like f/22 due to diffraction as Shun stated. Most lenses have a sweet spot around f/8 for optimal optical performance. I've used the 24mm f/2.8 Ais and the 24mm f/2.8 AF-D extensively on multiple MF and digital bodies (currently the D300) and have always been pleased with its performance. In fact, I'm going out with one lens tomorrow and I just took the big and heavy 17-35mm f/2.8 off of the D300 and put on the smaller, less obtrusive 24mm f/2.8 AF-D.</p>

<p>The 24 f2.8 D is a great great lens. It is not nearly as amazing as either the 14-24 f2.8 or the 24-70 f2.8 (which may be the sharpest lens Nikon has ever produced *at most working apertures). Nevertheless - the 24 2.8 D is a wonderful lens for the money.</p>

<p>My bucks are on the 24MM F2.8 AIS and Bjorn. The man knows what he's talking about. The 24 and the 85 F1.8 are a great lightweight combination out in the field.</p>