Malcolm, Sorry to join late...
If you *absolutely* have to have WR lens, then I think that 16-85 is preferable. The difference between 18 and 16 mm on wide end is significant. It will give you more interesting compositional opportunities. The difference between 85 and 135 mm on the long end is less significant, because both are part of 55-300 range.
However, if WR is not mandatory, then I should suggest that neither of these lenses is interesting. At least to me they are not. I prefer faster lenses, for these reasons: possibility to get sharper images at wider apertures, more play with DOF, more options for low light photography without having to raise the ISO too much. To that end I suggest Sigma 17-70 lenses. If you can, Sigma 17-70/2.8-4.0 Contemporary is said to be very good. If you cannot (shameless plug here), I can easily enable you with very cheap Sigma 17-70/2.8-4.5 as I am going to upgrade to Sigma 17-70/2.8-4.0 Contemporary anyway.
There is another option - you could buy Tamron 28-75/2.8 or Sigma 24-60/2.8 (another shameless plug, as I want to sell mine to finance that upgrade, I mentioned above). They would give you widest aperture and get you ready for incoming full frame camera, should you ever want to upgrade. Both are inexpensive these days and having had the former and having the latter, I should say - they are quite excellent.
Sorry for the plugs... HTH Boris On 10/28/2015 23:29, Malcolm Smith wrote:
I have the opportunity to add either an 18-135mm WR lens, or a 16-85mm WR lens to my collection at a discount. In the past I would have jumped to add another lens, but as I already have the 18-55mm WR & 55-300mm WR lenses, I am struggling to see what advantage I would gain by acquiring either of these. I don't want equipment to sit in boxes, I want things that will get regular use. Is there any point in considering either of these, just in case I'm missing something that makes one worthwhile? Thanks, Malcolm
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