Do you want wide angle or ultrawide angle? There is a lot of difference between 12mm and 15mm.
Sigma 8-16
When shooting dx, it is best to go with the dx wide angle offerings. 15 on DX is not particularly wide. There are many dx wide angles to choose from. Since you will have to sell it if and when you go full frame, I suggest buying used. The Nikon 12-24 seems to hold its value better than others. I had a Tokina 12-24 dxII. Bought new for $499. Sold it for around $200 when I got my full frame camera. Got the Sigma 14-24 2.8 to go with my D610.
There are actually some that will work to some extent on full frame. In other words most DX lenses will vignette on a full frame sensor, some lenses more than others and some zoom lenses more so at some focal lengths than others. I can't give specifics but maybe a little research could point out lens models that could work on full frame as well.
I am aware of this. I was able to shoot my Tokina at 18 and above without vignetting. But that left me without the very wide focal lengths one wants with a lens like that. I decided that sort of compromise is not what I wanted as I stepped into full frame shooting. Good that I got my D610 used and at a good price as I have bought several nice new lenses for it!
My favorite DX lenses on my D600 is the Sigma 30/1.4 Art, Nikon 40/2.8 macro, and Nikon 85/3.5 VR macro. None of my DX zooms work very well.
Definitely. All about personal preference. 18mm on full frame was just as wide as the 12-24 was at 12mm on dx. I had my issues with the Tokina--massive ca's. And, I did want to use fx lenses on my fx camera. Not crazy that only have the focal lengths of the lens were available to me. Plus, I had my vision of some of the lenses I would get for my D610 before I got the. Like a nice 14-24 2.8 (or 15-30)! Often enough, with my 12-24 dx lens, I felt limited by the 12mm limit. I don't feel that way about 14mm on fx.
I bought my Sigma 10-20 a long time ago. At the time I could have bought the Tamron and gotten 12mm, the Tokina and gotten 11mm, or the Sigma and gotten 10mm. I didn't think I needed 10mm for any serious use but thought it might be fun to play with. That's pretty much how it has turned out, but I do go all the way to 10mm a good percentage of the time. I was concerned about cost and weight when I bought my FF UWA so I bought the Nikon 18-35.
Do you miss the extra wide fls? I was concerned about cost and weight myself. But, I am an opportunistic shopper. I hold off on buying when I want a model outside my budget. Then, if and when it drops, I move quickly. The Sigma 14-24 went on one of those B&H flash sales for $899. Jolted me out of my Tammy/Sigma debate and I got it. I have a sling strap and that manages the weight quite nicely. I have been eyeing a 150-600 type lens for years. Liked the Tammy G2. Didn't want to spend $1300. Saw it used for $750 after wanting it for years. Got it. Once the cost goes down, my worries about size and weight do, too!
Pretty much the same for me - I found the wide end at 15mm efl of my Tamron 10-24 unexpectedly useful for capturing large buildings like cathedrals and town halls in cities where you can't get far enough away from the subject . You need a lot of free border to do perspective adjustment in post - a lot more than I guessed on my first outings. Just not the same as a proper tilt shift lens - maybe someday ....
I like my 18-35 (on full frame) and think it will be useful for landscapes but I think eventually I will end up buying something wider.
Dont know it myself but Thom Hogan's list of recommended dx lenses ( link in a previous post from me in your thread ) classifies it as not unconditionally recommended and said:
