Hi Jett,
I don't use a Sealux, but can still offer some suggestions:
1) Measure the diameter of your port. If it's anywhere from say 90mm to 115mm, you can find a Woody's diopter that works with your port. This gives roughly 30% magnification. You can check it out at:
http://www.nexusamerica.com/ under "Accessories"
2) You can also check out the MacroMate solution at
http://www.backscatter.com/HostedStore.Las...f3cfbee847c5b3dIt's much more expensive, but yields a 100% extra magnification (2:1 with a 60mm or 105mm lens).
3) Seacam are also working on wet-attached diopter lenses which look really promising and may be compatible with your port, but these may not available for some time. You can find out more at
http://wetpixel.com/i.php/full/seacam-wet-diopter/ or find out more by contacting your local rep:
http://www.seacam.com/en/kontakt/kontakte.htmGood luck,
Mat