Tamron 24mm f/2.5


This review is of a unique lens, though still applicable to the general Tamron 24mm lens.

I say unique because my copy was created by a machinist friend of mine who took a Nikon 24mm f/2.8 AI-s barrel (and iris) and installed the Tamron 24mm f/2.5 optics. The result is a lens that mounts natively to a Nikon body with a working AI aperture ring but has the better Tamron optics. Normal Tamron 24mm lenses are not available in a Nikon F mount and require an adapter, losing the AI aperture ring.

The result for me is the great optics of the Tamron with the ergonomics and usability of the Nikon. A win-win.

With that in mind, you can skip a lot of the specifications discussion as your lens will likely not be at all like mine, however the optical performance remains the same.


The lens is setup with 11 elements in 9 groups.

Maximum Aperture: f/2.5

Minimum Aperture: f/22

The diaphragm is 9-bladed, producing a high-quality bokeh.

The aperture is of course from the Nikon barrel being used, not the native Tamron lens. On my lens the maximum aperture of the ring is f/2.8 but optically it is f/2.5 on the inside.


Again, keep in mind my version of this lens is unique. The Nikon barrel is all metal and the AI aperture capability makes the lens very useful on modern cameras.

Overall the lens is relatively small and light weight making it easy to slip into your camera bag as another option when you're in the field.

The lens is strictly manual focus and manual-set aperture (though automatic aperture to compose the shot wide open and then constrict the iris for the photo).


Wide open the lens is very sharp in most of the center. In the Twenty-Something-mm range it is perhaps the second best lens you can get for sharpness.

Sharpness does tend to fall off in the corners until f/5.6 when most of the image is rendered with excellence.


Nikon makes a decent 24mm f/2.8 available in auto focus and weighs twice as much, but this f/2.5 from Tamrom is much sharper in the center and remains sharper stopped down. Pick up the Tamron option if you want sharper images.

Nikon also made and continues to make a f/2.8 AI-s version of this lens. That is where my barrel is from. The AI-s lens is so good it is still made today with manual focus with manual focus. This Tamron is better.

But, if you want the best sharpness in the 20-something range the Nikon 28mm f/2.8 AI-s is the winner.


Following are some sample photos to demonstrate the power of this type of lens and some general uses which will likely yield good results. If you shoot things like these, then this lens may be a good one to think about adding to your camera bag.

Check out more photos I have shot with this lens in my Flickr Album.