"It doesn't have to be Nikon brand so long as it's a good lens. "
That's a contradiction. The only off-brand I would tolerate is a Zeiss...please, no holy wars here but you simply won't beat Nikkor glass (other than Zeiss) with any off-brand. And the prices have come down in the used market enough that it makes no sense from a money perspective to not get Nikon, either.
My experience matches most here, 24mm is about as wide as I've found useful - any thing more I find I crop in order to get what I originally envisioned.
That said, I'd think about the 28mm f/2 -- wide, fast and sharp. The 2.8 version is sharp also but why not live a little.
The 28mm F2 Nikkor is one of the best 28's ever made in my opinion, heard excellent reports on the 24 as well. I have the 20mm 3.5 that I also use a lot, great lens and very compact....takes 52mm filters as well. Probably though, with the lenses that you have, a 24 would make sense.
My most used lens is the 24/2.8, I use it as my normal focal length. I also like the 20/3.5 because it's small and takes 52mm filters.
The first rule of Nikkor 28/2.0 club is that there is no 28/2.0 club.
Originally Posted by tony lockerbie
The same rule goes for 20/2.8 club.
Colin, all wide angles require getting closer and closer. Until you're literally in the scene (but not on the film). Cropping or the need for it is a symptom of not being close or immersed enough.
35mmf/2 or 34mmf2.8
Originally Posted by EASmithV
If you care about size, I'd recommend Voigtlander 20mm/F3.5 (very small, makes your nikon compact).
I use it, and I like it.
Take a look for instance at Ken Rockwell's review here (sorry I couldn't get any other review quickly).
I could debate all day and still not be settled: my personal favorite wide angle Nikkor (manual focus, of course) is a tossup between the 24mm F2 AIS and the 35mm F1.4 AIS. For really wide, I like the older 20mm F3.5 AIS (52mm filter diameter) - sharp and compact. Although I also own the 18mm F3.5, I find myself carrying the 20 because it (with the HK-6) take up so little room in the old Domke...
All Nikon wides are excellent, but some are more excellent than others. Which, depends on your preferences and style.
In the 17-24 range, probably the best all around lens is the 20/2.8. If you want to go smaller and lighter but stay at 20, then f/3.5 AI-S and f/4 might be better (they don't have CRC though, if you intend to shoot close to MFD). If you want cheaper, go with the 24/2.8.
For me, 24/2 does exactly what I want at this FL, not more and not less. I shoot low light candids with it so its questionable out-of-center sharpness is of no significance to me.
Outside 17-24? For low light it's the 28/2, which also does landscapes really, really well. You've gotta check out its "boke" as it's not everyone's cup of tea. 28/2.8 AI-S has very little, if any, distortion, and is remarkably sharp up close. Its MFD is smaller than that of the 28/2 and the lens itself is smaller. I've had both but later sold the f/2 and kept the f/2.8 AI-S, because of its size, MFD and sharpness close to it, color and OOF rendering.
My "normal" lens is the 35/1.4 AI-S. It's not cheap and many people don't like the way it draws between f/1.4 and f/2, but if you are not one of them then you won't find anything like it without going big and heavy.
I've heard people saying that Tokina 17/3.5 is a great lens and I've seen pictures made with it, but I have never used it so can't comment.
My ideal combinaton is 35mm + short tele + 20 (or 21mm).
That said, if you're not adding anything else wider than your 50mm, I'd go for the quite nice 24mm 2.8 (or even 28mm).
The jump from 50mm to 20mm or less would be too much.
I also have and like the Vivitar/Tokina 17mm (and find it far better than the Tamron 17mm many reccomend), but for the reasons above, I certainly wouldn't get it as my only wide...
My Nikon kit is a 50/2 (non-Nikkor), 28/2.8 AI and 20/4 AI. Both the 28/2.8 and the 20/4 are wonderful lenses and the 20 is very wide indeed. While I wouldn't mind owning the 18 over the 20, I don't think I need to go that wide 99% of the time and it's great that I can share my 52mm diameter filters between my three lenses as they all have the same-sized thread. I'm pretty sure that you'll have trouble finding a bad wideangle Nikkor, so no worries on the quality.