Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    Name or NavList Code:
    Email:
       
    Reply
    Re: ND1000 filter - a data point
    From: Noell Wilson
    Date: 2022 Oct 29, 10:14 -0700


    I checked the ND1000 and it measures 0.0477” (1.21mm) thick at 4 places around to the best of my ability with a 0.001” micrometer. I’m estimating the 0.0007”.

    Hopefully, current glass manufacturing has eliminated wegness these days. I’ll check the new one when it arrives.

    I took the filter apart and the 40mm thread shell holds a 37.5mm diameter glass. Extending that, I ordered a 43mm filter and I’ll check it too. Trying to grind 0.5 mm off the diameter without breaking it may end the quest.


    It looks like I may be buying some parts from C+P to get everything right.

    My first experience with light leakage and the sun was with a zero magnification plastic sextant. It scared me when I thought of making that mistake with a magnifying telescope.

    Regards, Noell

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site