Summary: Sigma 12-24mm f/4.5-5.6 EX DG HSM shows pretty decent performance throughout the zoom range from f/8 and on. At wider apertures the lens exhibits some weakness around borders (primarily in the 12-17mm range), so you should be prepared to stop down to achieve the best results.
Conclusion: A huge field of view, coupled with a sensible zoom range that is still useful on cropped sensor cameras as well as the full frame that it is designed for make this lens extremely practical. A great item of award winning kit, especially if you use more than one format of sensor.
Pros: Enormous field of view, Amazing control of distortions, Solid build quality with good protection of front element
Cons: Difficult to use front mounted filters (Though not impossible), Bulbous front element needs careful handling.
Excerpt: There's no getting away from the fact that this is a bulky, wide (in the physical sense) lens and weighs in at 600g. As you'd expect from the weight, build quality is robust, and it's a very solid, well-finished lens. It's finished in matt black and sports a HSM motor for reduced AF noise.
Sigma AF 12-24mm f/4.5-5.6 HSM DG II - Review / Test Report
6 May 2009
Conclusion: The Sigma AF 12-24mm f/4.5-5.6 HSM DG II is an exciting piece of equipment. The field-of-view at its 12mm setting is simply stunning and regardless of any performance debate this is simply a substantial differentiator / selling point compared to all other ultra-wide DSLR lenses.
Sigma AF 12-24mm f/4.5-5.6 EX DG HSM - Review / Lab Test Report
28 March 2009
Conclusion: The Sigma AF 12-24mm f/4.5-5.6 EX DG HSM is the most extreme full format ultra-wide zoom lens around and it is still a "mainstream" ultra-wide lens when used on APS-C DSLRs. If you're looking for a future-proof "duo-format" lens in this class - well, here it is.
Sigma AF 12-24mm f/4.5-5.6 HSM DG II - APS-C Format Review / Lab Test Report
2 March 2009
Conclusion: The Sigma AF 12-24mm f/4.5-5.6 HSM DG II is the only "one size fits all" (formats) ultra-wide zoom lens on the market. It can give you decent results and truly extreme views on full format DSLRs and it is very good along across the more "conventional" zoom range on APS-C DSLRs.
Sigma AF 12-24mm f/4.5-5.6 EX DG - Review / Lab Test Report
28 February 2008
Conclusion: The Sigma AF 12-24mm f/4.5-5.6 EX DG is the most extreme full format ultra-wide zoom lens around and it is still a "mainstream" ultra-wide lens when used on APS-C DSLRs. If you're looking for a future-proof "duo-format" lens in this class - well, this may be it.
Excerpt: In deze Sigma 12-24 mm II DG test voelen we een lens aan de tand die ontworpen is voor gebruik op een camera met een FX / volformaat sensor. Deze Sigma 12-24 mm verscheen in 2011 als opvolger van de beroemde Sigma AF 12-24mm f/4.5-5.6 EX HSM DG.
Pros: Aantrekkelijk brandpuntafstanden bereik: Ultra groothoek zonder zwarte hoeken, Hoge beeldkwaliteit: hoge centrum scherpte, zowel chromatische aberratie als overstraling zijn zeer goed geminimaliseerd (voor een groothoek op volformaat), Zeer solide gebouwd, Aantrekkelijke prijs / kwaliteitsverhouding
Cons: Zichtbare lichtafval, Lagere scherpte aan de randen, Geen ingebouwde beeldstabilisatie