Hi,

does anybody know the diffrence between th Dom 180F and the Dom180U from Sealux.
I own a nikon fisheye 16mm wich need the Dom180F and I own a nikon 17-35mm that need the Dom180U with 45mm extension. to buy both domeports is too expensive and to much lugage when travelling. sealux said the nikon 17-35mm would also fit the Dom180F with 60mm extension.
Does anybody know about the quality of the sealux domeportoptics comparing with subal domports ( wich I have at the moment, but I want to make the change to sealux).


Rob

180U and 180F glass is identical. just the port is different:



The 180F allows using a true 180° fisheye. The Nikon 10.5mm DX would cause vignetting when placed behind the 180U as you can see in the drawing above.

I use the 180U with wideangles and the Sigma 15mm fisheye too as it delivers only 108° on my camera. I am pretty sure you could do the same with the Nikon 16mm as length isn't so different to expect vignetting.

The 180U provides a little bit better lens/dome relation(positioning) especially with wideangles.

If you just want to pick one port and you are absolutely sure you won't be tempted by the 10.5mm fisheye, you can pick the 180U. But just make 100% sure, the 16mm fisheye wouldn't give black corners behind the 180U. I am quiet sure it won't (like my 15mm fisheye). If you have problems to find out, you could send me some data of the lens and I could check.

Or get the 180F in order to have an 10.5mm path.

By the way, if you ask Sealux, they will tell you the 180U won't be right for a 15/16mm fisheye. They tell you "the fisheye port for a fisheye". They don't seem to have an idea what field of view the lens delivers on a cropped sensor and that the 180U allows the better optical placement.

Julian