How does the JVC WA converter match up against the Cavision and Redeye? Vignetting? CA? Barrel distortion?

It's about 500 bucks at B&H
JVC 0.82x Zoom Through Wide Angle Converter Lens for Fujinon TH16x5.5BRMU Lens (WCV82SC)

http://tinyurl.com/2tjpl8

I have the 17x, and it's the same thread mount (82mm) - but the recommended adapter is the WCV-85C 0.7x. ok hold your breath.... $2,799.50 at B&H!!
The WAT-85C 0.8x is $1,430 Ouch. I'll bet the JVC (actually made by Fujinon)WCV-82SC works on my lens too and vice-versa. I'd love to see some real comparision test, as this is a big price spread.
I think I'll be going for something decent, and in the $500 price range, it just seem ridiculous to spend more. With the 16x only about $800 street, spending any more on an adapter wouldn't seem to make sense either.
Meanwhile - I haven't found rental of the 13x in NYC yet. Abelcine lists it for sale, but not in their rental list. Maybe I'll just call and request it - along with the PL adapter - they have a nice selection of 16mm PL lenses....

There are other threads on these -- on this front page, I think.

The JVC .8x converter is excellent.

The similar Century .8x converter is almost the same, with perhaps a very slightly sharper image in the far corners, but not seeable by most.

The converfters are zoom through.

To go wider, .7x and .5x, the Century adapters are "industry standard," and have been used for years by many users.

Get the JVC converter, screw it on, and forget it.

As I understand it, the JVC converter take it from 5.5 to 4.5 on the wide end of the lens?

As I understand it, the JVC converter take it from 5.5 to 4.5 on the wide end of the lens?
I don't know what it is in terms of millimeters. However, in terms of view, it increases what you see by 20% (.8x). (If you multiply .8 x 5.5. you get 4.4.)

This is not a lot, but it helps in many situations.

More typical for lens adapters/converters is .65x-.7x, or an increase in view of 30-35%. For example, the Century wide-angle converter for the PD150 -- which many people are familiar with -- is .65x.

FWIW, the WCV82SC is a 0.82x adapter. The picture and nomenclature show it clearly as being a fujinon item, and it is specifically for the 16x. It is alarmingly close to the street value of the entire lens itself.
(official specs)
Converted Focal Length
4.51-72.16 mm (Fujinon TH16x5.5BRMU)
The page on the 13x fujinon lens has an attachment picture showing the frames of the 16x, with and without adapter and the 13x all at widest setting.