Sekstantti ja silmät

Tutustupa ensin sekstantin käyttöön ja kysy sitten uudelleen.

Ei oikein vakuuta tämä:
"Q: I bought a four inch sextant with six filters from Castle Navigation marked Stanley London. When the sextant arrived a warning was included that permanent eye damage would result if this sextant was used for sun shots.
I called them and was told that this warning was given since they did not know if the sun filters were adequate. Could you advise as to how I could determine whether the filters are alright and if not how they could be corrected?
A: I'd check with a eye doctor if you are concerned. They are probably just covering themselves. I choose the appropriate filter (or combination) without the danger of magnification by lineing them up off the sight path and then holding the sextant up at arms length toward the sun. If the image of the sun is sharp and easy to look at through the filters alone I figure the filters are ok. Then I push them down into the sight path and proceed."
http://www.nav.org/cel/faq.html

Sinisilmäinen sekstantti on paras.

Onhan niissä filtterit. Ennen vanhaan kokeneilla kippareilla oli musta lappu silmän päällä, kun eivät viitsineet filtteriä käyttää, tai eivät filtterit muuten olleet kunnossa.

Filttereissä on eroja.

http://www.hus.fi/default.asp?path=1,32,660,546,968,2326,12365