Sony NA-6XXX and Inon UWL100 Achromat lens combo

[Nemrod]

For what it might be worth to anyone in the future, I have been able to put together my NA-6400 Nauticam and my old Inon UWL100 Achromat lens with Dome Conversion successfully. Many people had or still have these old Inon wide angle lenses (commonly used on the Oly 5050 and Ikelite combo as was mine) and they are of high quality, fully coated glass and they are achromatic design unlike many wet optics today. The lens with dome is advertised for a 130 degree semi-fisheye lens with the dome installed.

My Inon UWL100 was the Type 2. I converted it to a Type 1 via the adapter ring available from Divervision, it is an Inon part. I purchased a Rokinon f2.8 24mm lens for my Sony A6400. This is a relatively inexpensive prime lens with good reviews and cost effective. And it works just fine with my A6400. A good street photo lens or prime travel lens. I then purchased from Reef part number 36139 Macro Port 35 and the part number 83250 M67 to Bayonet Converter (II).

Preliminary testing is completely positive with no vignetting. Focus is fast through the combination and accurate. FOV is not quite as wide as the Nauticam WWL-1 and not as clean in the corners but completely acceptable, especially if you already own the lens. Since it an all glass and metal lens, yes, it is heavy but not as large or heavy as the WWL-1. The Inon lens with the Nauticam adapter bayonets quickly on and off. The Rokinon 24mm is good on it's own merit for fish portraits, keep in mind it is a 35mm FF equivalent lens.

Thanks to the Wuhan virus I have not been able to go anywhere, even the pool, to further verify the FOV and overall quality. But, having used this lens extensively with a variety of cameras in the more than one decade I have owned it, I am confident it will not disappoint me. That said, I am not a pro, do not do photography for a living so I am not as hard on minutia as some seem obsessed with these days. This lens and port combination is not supported on the Nauticam port charts BTW.

N

 

[Nemrod]

Here is what I am talking about:





The Inon UWL100 achromat also work with the kit zoom and Macro Port 45 but is not as optimal as the Macro Port 35 with the Rokinon 24mm. The kit lens must be zoomed to 24 or 25mm and because the zoom function retreats the lens from the port slightly the FOV is somewhat less and I begin to see "coke bottle" effect in the very corners. But still very useable (my opinion). JFYI, the Rokinon 24mm f2.8 is the same product as the Samyang 24mm f2.8. The Inon UWL100 (M67) is a achromat lens. It has an additional element that brings blue and red wavelengths to the same focus point. As described by Inon 5 elements in 4 groups as opposed to for example the Inon UWL100-28LD with 4 elements in 4 groups. Not an achromat and very few wet optics are. Thus my interest in it.

The Sigma 19mm f2.8 and the WWL-1 compared to the Rokinon f2.8 24mm, the WWL-1 and Sigma combination appears to be sharper, especially in corners and the FOV is comparable but slightly wider. The Inon UWL and Rokinon combination is somewhat smaller and more compact and not quite as heavy.

I would not really recommend the Rokinon and Inon combo unless you already have the Inon lens or can find one with the dome at a good price. Not because the Inon and Rokinon are not a good set up, they are, but because the Sigma and WWL-1 just are better and from a $ standpoint, only makes sense if you already have the Inon lens. And got the Macro Port 35 during the Nauticam 15% off sale .

One interesting thing, just as a consideration, the Sigma f2.8 19mm lens which is supported on the Nauticam port charts as ideal for the WWL-1, is NLA. Though there are still some NOS and in the used market fairly plentiful.

Another unsupported lens combo that might work is the new Nauticam WWL-C with the Sony 16mm f2.8 and E16 Pancake Port 36126. It is supported for the kit zoom 16-50.

N