Yet another Nikon lens question.

First off little background info. I have been shooting Nikon D7200 since it came out, mainly macro (90%) at Lembeh or similar destinations. Some wide also, like trip to Socorro. For the wide, I have used Tokina 10-17 with the small 4.33” dome.

Now its time to get a new setup (gear lust, it hits hard). I am strongly leaning towards D850 (I am looking for Z options also, but not likely). D850 should be enough for me for the next 3-5 years, I guess. But this is not the actual question.

It seems like I will be doing more “wide-angle” places (still doing macro as I somehow love the muck) in the future, like Triton Bay (Whale Sharks and reefscapes), Alor (Reefscapes, jettys), Raja Ampat and possibly Cocos Islands and more Socorro.

As I am still bit newbie with the whole wide-angle thing, I am asking for some help with lens choices.

I would most likely be looking only one lens and I have most likely narrowed it down to the 16-35 or the 8-15. I know these require large dome and big extension which is not the most convenient choice when travelling.

I recently met someone on a trip who had the Nikonos RS 13mm, and he was full of praise for the lens. I have done some internet digging and it seems like this is good lens also. Actually, his words were “It’s the only WA lens you need for Nikon”.

I think its either the 8-15 or RS 13, because i think fisheye is the better choice for me instead of the 16-35.

Given the price for all the choices (including domes/extensions/conversions) are fairly close to each other, I really don’t know what would be the actual best choice.

Have you thought about the Sigma 15mm,  Sokrates?

I used that a great deal on the Nikon D800 and it became my go-to WA lens. It doesn’t need the 230 dome like the 16-35 and is great for reef shots and shots with divers. Maybe not so good for larger fish that keep their distance. 

The Sigma 15mm will give you an excellent FE at much less cost and bulk - and, usually, with no EXR.

Few pics attached to give you an idea.

I’ve found the 8-15  to be very good, oddly, on the DX-sensored D500. I also use it on my topside FFs, but on FF it’s not really a zoom but more of an option between a 15mm FE and a relatively limited circular image FE. On a DX camera there is small amount of zoom. 

No experience of the Nikonos - sadly!

I shot a D850 (Nauticam housing) for a few years, until August when I started using a Z9.   I used a D810 underwater before the D850.

Wide angle options are limited, for sure.   I see it as a choice between fisheye (8-15), rectilinear (16-35), and specialty optics (see various expensive Nauticam options).    As I do not like fisheye, the choice of 16-35 was pretty clear to me back in 2015 when I first bought a housing for my D810.   

At least with the zooms, you have competing tradeoffs.   The 16-35 requires a huge dome that is difficult to ... well, everything, really.   AND it needs a Sea and Sea Internal Corrections Lens on it to make the corners acceptable.   The 8-15 is easier to travel with - but it's a fisheye.

I can't see a wide prime.  I think I'd be sick of the same viewing angle after a few dives.  Probably crop even more than ever.

As for extension, I use a 90mm extension with my 230mm dome.  I find it just holds 6 arm clamps, plus the one for the focus light, so it becomes less an issue when packing.   The 230mm dome port?   Nothing but issues there.  Can't put anything inside it.   Have to really pad around it.   And it's huge.

I shoot both the 8-15 (which for me means 15 since I'm not keen to the circular fisheye look) and the 16-35 both behind a 230mm domeport. Rectilinear lenses gives a different look compared to the extreme distortion caused by the fisheye and I think they are very useful for sharks and pelagics in general. However, in my opinion a fisheye is lens that every WA shooter should own. Reef scenes with the rectilinear doesn't give me the "right feel".

Another route, as Craig mentioned, could be the inexpensive Nikon AF 28-70mm f/3.5-4.5 behind a Nauticam WACP. The new WACP-C sounds interesting and could be a solution that offers both optical quality, similar costs and a reduced size and weight compared to a 230mm domeport, plus flexibility with a great zoom capability. I don't know how the final product performs but I'm also considering to take the plunge.

Frankly, I think you should stick with the D7200 and Tokina.  If you must upgrade, a D500 would be a better camera and you could keep using the 10-17. That lens gives you useful flexibility on crop-sensor that the 8-15 does not, on full frame. You could use the 8-15 on an APS-C camera like yours but the increase in quality is marginal and not worth the money, in my view. I switched from a D800 to an APS-C mirrorless; its more complicated (I have to remove the port and lens to remove the camera usually). It's slightly less heavy and I was keen to try water contact optics, the WWL-C, which is less than $1000. It's great, and 130 degrees sounds wide, but my Sigma 8-16 is wider and gets more use. You can't use the Tokina 10-17 with mirrorless as the AF doesn't work, so I bought an 8-15 zoom fisheye which does the same job, largely, as the Tokina on a crop sensor. Really, save your money. If you want better quality, go somewhere with clearer water. Check out Greg Lacoeur's work with the Tokina and D500...

I will defer to the other folks on the D850 as I use the D500 underwater.  Nonetheless, I thought long and hard before selecting the D500 over the D850,  and in large part it was the dome port size issue.  Things might be different now with the WACP lenses.  So a couple of things to factor in...  I use the 8-15 and since getting it, the 10-17 largely goes unused.  Admittedly, the resulting picture quality is only marginally better and the lens is bigger and much more expensive.  The 8-15 is more flexible with a cropped sensor camera than a full frame.  As noted above, for full frame it is essentially a 15mm lens.  I can use it with the D500 in a 100mm dome, on full frame I suspect you would not want to go below a 140.

But then there is the other option as mentioned above;  the WACP.  They are expensive things, but since you are buying new anyway, I am not sure the cost of a WACP-C  and 28-70 would be that much more than an 8-15 and 140 or larger dome or a 16-35, corrector lens and 230mm dome.

I have no experience with shooting wideangle underwater with the D850, so I am not recommending anything, just mentioning something you might want to consider.  If you end up with a D500 and are interested in a fisheye, I can recommend both the 10-17 Tokina and the 8-15 Nikon, depending on your cost considerations.  Either works well in a 100mm mini-dome or the 140mm dome.

By the way, the Tokina 10-17 for DSLRs has been discontinued.  If you want one, they may become hard to find in the not-to-distant future.