Choosing a lens, part 3

Sigma 50-150mm f/2.8 DC OS

I think I have also made up my mind that I will not buy the Nikkor 70-200mm f/2.8.  It is an excellent lens, just not for me, not for a DX camera body.  The 70-200mm on the DX body would be like a 105-300mm on a FX body.  If I were using it in a wedding shoot, I would be missing a fairly important range.

I already have a Tamron 17-50mm f/2.8 VC.  It is a great lens.  The vibration compensation mechanism is not as good as Nikon's but then again, the Nikkor 17-55mm DX does not have any VR.  I ran some handheld tests today and like I said before, VR is a big deal.

What about the upper focal range?  I'm thinking the Sigma 50-150mm f/2.8 DC OS would fill this gap really well.  I have seen only great reviews of this lens and by the way, this is the "DC" version. This lens is sharp throughout the range, even wide open.  I would use it in combination with the Tamron 17-50mm for wedding shoots.  Together, they are similar to the 24-70mm and 70-200mm combination on FX bodies.

Now, where am I going to find this lens?  I'm very hesitant to pay the retail price of about $1200.  The purpose of this lens for me would really be for the occasional weddings and conferences.  I see using it for mostly indoor shoots, and even then, I would use my all purpose 18-200mm for parties.  I would not use the Sigma 50-150mm or the Tamron 17-50mm for hiking, camping, traveling, and nature photography either.  For that, I use my Nikkor 18-200mm and Sigma 10-20mm lenses.  In these types of photography, there is less of a need for the f/2.8 aperture.

So, I'm looking for a second hand version from someone upgrading to an FX body.  I don't see it anywhere yet.