New Sigma lenses - but why?

[TristanP]

Sigma has announced (http://www.sigmaphoto.com/news/news.asp) two new lenses - 70/2.8 EX DC macro and 50-150/2.8 EX DC tele zoom. Aside from being lighter and smaller (a little), do they really gain anything by selling these? What's wrong with the 105 macro and the 70-200 telezoom they already make? Make this make sense to me.

[Jeffro]

Is it because they are for D-SLR's with APS-C size sensors? Kind of like the EF-S Canon lenses. I could be wrong. :dunno

[HeldDown]

I would LOVE that 50-150 f/2.8. 80-200 has been SLIGHTLY too long too many times!

[TristanP]

Is it because they are for D-SLR's with APS-C size sensors? Kind of like the EF-S Canon lenses. I could be wrong. :dunno
The Sigma DC line is for crop sensors, so I suppose. I would rather use glass for full frame bodies and get the benefit of just using the best part on a crop camera.

[limbik]

Good question... The 70-200 Macro at least made some sense, but I'm still waiting for a 100-300 f4 with OS.