As you see in the picture below the Sigma 2.8/10 mm is rather compact. It is smaller than the circular Sigma 4.5 mm and than the classic kit equivalent – the Sigma 17-70 mm. It is something worth notice, especially that the tested lens has an in-build mini petal-type lens hood. This fact is connected with an interesting detail. Such a hood makes impossible to put on a cap directly. Sigma decided to use here an invention known from the 12-24 mm model – a metal adapter for the cap. What’s important it has a mount for the filter thread, 67 mm in diameter. There’s a problem, though. The adapter, in order to contain the lens’s hood inside, must be quite high and it makes the field of vision significantly narrower while photographing. Using standard filters we can practically forget the 180 degrees field of vision. It is possible, though, to use additionally special smaller filters on the rear end of the lens and they won’t limit the field of vision for sure.
The picture below shows a comparison of two shots, one taken with the bare lens and the other with the adapter and a filter.
The Sigma 2.8/10 mm is from the top Sigma lenses shelf, marked EX. The build quality is difficult to flaw. We have here a metal bayonet, a comfortable manual focus ring and a clear distance scale window.
The inner construction consists of 12 elements in 7 groups. What’s strange, the manufacturer doesn’t boast of any low dispersion or aspherical elements. There is a 7 diaphragm blade aperture, which can be stopped down to f/22.
Apart from the adapter, the lens hood and the cap mentioned above, the buyer gets also a soft case.