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.

Choosing a lens

Just yesterday, I was browsing for and reviewing the Nikkor 17-55mm f/2.8 lens.  It costs at least $800 used.  A few months ago, I was browsing for and reviewing the Nikkor 70-200mm f/.8 lens.  Again, this beast also costs at least $1300 used.  It begs the question:  do I really need any of these two lenses?  I like that they are really fast, but there is no VR.

ExposurePlot:  graphs of 234 photos.

Besides that question, my other question is, how often do I shoot in a certain range to justify such an expensive purchase?

I ran a quick search on Google and landed on one piece of free software called ExposurePlot.  I just had a quick look and I like it already.  I ran it against 234 photos I took at a niece's birthday party.  All the shots were made indoors with flash mostly.  I forgot now what ISO values or aperture settings I used.  This software answers this question in minutes.

I can see I left my camera on ISO 1600 the whole night, as shown by the big red bar.  Since I used Aperture Priority virtually all the time, with flash on, the shutter speed is maxed out at 1/60 seconds as shown by the big green bar.  I can see that a few times, I turned flash off, and they show up as those tiny green bars.

Now, for focal length--and this must be taken into context of an indoor party shoot--I spend most of the time shooting between 18-55mm (DX).  The graph converted my focal lengths into 35mm equivalents and I am not sure how to turn off that conversion yet.  I do shoot in the 70-200mm (DX) range but not as nearly often.  Overall, I can see that I do use the full 18-200mm range in a given night.

If I were to purchase a 17-55mm lens and a 70-200mm lens, I will likely use the 17-55mm much more often than the 70-200mm, but will I likely want to switch lenses during a party, or will I simply adapt (i.e., getting closer)?  I have brought just a 50mm lens to parties before and I was forced to adapt.  Hmmm...

I have to run now.  I will play with this software more a bit later.