Nikon 16mm, Nikon 18mm, Sigma 15mm

Seeking comments & experiences with these lenses. Pros & cons. Especially interested in edge sharpness & distortion (barrel/pincushion). Looking to replace my 12-24mm on Nexus D70 system. Thanks.

Hi JC,

I've used the Nikkor 16 and the Sigma 15mm but not the 18. I can say that I can't see a difference between the two fisheyes except for $400.

Owning a fisheye is a must, but you should try the 10.5 if you don't already have one. The other two are fairly cropped but do show unacceptable (at least to me) barrel distortion when used topside.

Cheers

James

I use the Sigma 15 over the 12-24mm most of the time....closer focus and sharper corners with my dome setup

I understand the the Nikon 16 is excellent, but it doesn't focus as close as the 15mm...nice feature for CFWA

Karll

I've experienced loss of edge sharpness using the 12-24 with an extension ring on my Aquatica D2X housing. Using variable zooms underwater behind a dome port can't give you the best edge sharpness at all focal lengths. Using a variable zoom UW is new to me so I'm still testing to see at what focal length works best. There is nothing like a 15 mm lens on a Nikonos for sharpness throughout!

I've just tested several domes & various extension rings, trying to find the optimum setup for the 12-24 on my Nexus D70. None had sharp edges. I did get good edge results using a +4 diopter, but the pin cushioning was really bad. The nodal point of the lens changes as you zoom. I figure if I can only shoot at a restricted focal length I might as well just use a fixed lens vs zoom. Besides 12mm is a bit wide for me anyway.

JC,

I'm with Karl Dietz as I'm back to the Sigma 15mm all the time for wide shooting. Sharper corners, no rings to attach and focuses to 6", and fairly inexpensive! Also works well in either 6" and 8" dome ports on my Ikelite Rebel XT housing.

I depend on it so much I bought another one last week!

YMMV

dhaas

I also like the simplicity of the Sigma 15mm. Zooming with your fins usually gives better results anyway.

I also find that the 15mm is faster/surer to focus in low light than the 12-24mm AF-S notwithstanding.

I just received the 8" Ikelite port so I'll try again with the 12-24mm and see how I like it. I imagine though that I still will be using the 15mm for WA most of the time.

The 10.5mm is great for effect but harder to use. Its so wide its hard to keep unwanted clutter out of the photos. The 15mm is the sweet spot. Really wide but not too wide.

The Nikon focuses down to 10 inches, closer if you remove the bayonet filter at the rear of the lens (though then you can't focus at infinity -- usually not a problem for UW WA). I've yet to attempt a CFWA that the 16 couldn't focus on -- 10" from the sensor plane is VERY close to the outer surface of my dome. 6 inches (which the Sigma delivers) would be INSIDE most domes -- cool, but not often needed!

I'd love to see CFWA with subjects closer than 10" from the sensor plane -- I suspect such shots are very rare, very hard to light, and very dramatic.

I have the Nikon 16 because a mint used copy was slightly cheaper than a new Sigma 15. You can find good deals on these lenses on eBay pretty much all the time.

Regards,

Chris

karl: what ike port do you use with the 15mm FE ?

im not a technical expert, but i love the tameron 14mm rectalinear lens. i use it with a nexus 180 port

Ikelite 8".....I have the older Aquatica retro 8" and have used it several times....works great.....I have the new 8" coming and will try it out next month in Lembeh

Karl

Nexus has a 180mm port? After testing several ports & ext rings I'm no closer to a good 12-24 setup but I may have just found the key to the 17-55 setup If real life pics look good (vs testing in big tub) I might not worry about a wider lens. I would most likely be shooting the 12-24 in the 15/16-24 range anyway.

oops ment 170. like i said im not a technical guy!