1 yes. 2 85 x 1.5 . 3 i dont know.

I forgot to answer your second question, about why this lens does not have VR.

The reason is that this is a lens designed primarilly for portraiture with an FX camera. The rule of thumb for an FX camera is that the shutter speed should be 1/focal length or 1/85th. It is usually easy to maintain at least 1/85th shutter for portraiture, so they didn't include VR.

However, on a DX camera the rule of thumb is that the shutter speed should be 1/effective focal length or 1/127.5. This is a little harder to achieve, but is still fine for studio work, so it is still an excellent lens for a DX camera, even without VR.

If you are looking for a lens to do low ambient available light candids, the 85mm f/1.4 may not be the best choice. A better lens on your D300s might be the 50mm f/1.4. That will have an effective focal length of 75.5mm (on a DX camera), so you will be able to handhold without VR to a shutter speed of 1/75.

Another great DX lens for available light is the 17-55mm f/2.8 DX lens. The zoom range is perfect on a DX camera for parties, receptions, family pics, etc, and it is tack sharp at f/2.8.

This is an FX lens, meaning it will project an image circle large enough to cover an FX sensor (same size as a 35mm film camera).

Your D300s has a DX size sensor, which is smaller than an FX sensor, so the projection circle of this lens easily covers the DX sensor.

The DX sensor is said to have a 1.5X Crop Factor because with its projection circle, it 'crops' out 0.7X of the area the lens projects. And if you multiply the area of the DX sensor by 1.5, it will equal the area of the FX sensor.

The other requirement of this lens is that the camera must have a focusing screw driver. The D300s has a focusing screw driver (as do all of the higher end Nikon DSLRs).

So, yes, it will work on your D300s, and it is a wonderful portrait lens if you have a big enough studio. I say this because the 1.5X crop factor makes this lens act like a 127.5mm telephoto lens. This means that you will have to stand back quite a bit farther to get your subject to fit into the frame, so you need a bigger studio.

Also the depth of field of this lens will be slightly greater on a DX camera than on an FX camera. This means you will have to open it up slightly wider to achieve similar background blur on your D300s compared to an FX camera.

Yes. The 85mm f/1.4D, as all "D" lenses, will meter and autofocus with any Nikon digital camera with an in-body motor. The Nikon D80 is one such body that has an in-body motor.

Note that higher end bodies have more powerful motors so it will not focus as fast as say a D3S. In practice, though I haven't noticed the difference to be significant between the speed of this lens on my Nikon D70, D200 and D3.