NavList:

   

Reply

Brad,
Let me add something to my message.
As I said, I had both Freiberger and C-Plath certify my sextant.
This was about 10 or 12 years ago.
In Freiberger, the process was performed in my presence.
With a special, very interesting device.

In C-Plath, they did not allow me to enter their factory, and I could not
see what they did. Perhaps they did nothing, just wrote: Good for
practical purposes:-)

Alex.

> Hello Greg
>
> Sadly, no such service exists anymore.  (Someone, anyone, please please
> please tell me I'm wrong).  You can no longer have your arc calibrated by
> a
> metrology lab as a standard practice.
>
> There has been intermittent conversation on these boards as to how to
> calibrate the arc.  I'm still not sure that there is any broad agreement
> on
> the practices and procedures to undertake, in the absence of such service
> you requested.   Some feel star to star distances will work, a point with
> which I do not agree.  Others feel that the lunar distance can be made to
> work.  Possibly, but long term averages will be required and a further
> pre-requisite will be absolute mastery of the instrument and the
> measurement.
>
> Brad
> On Dec 26, 2013 7:58 PM, "Greg Licfi"  wrote:
>
>> ------------------------------
>>
>> Hi All,
>>       Does anyone know of a service that would check the certification
>> of a sextant and supply me
>> with a new calibration card? How much would this cost? Is it silly to do
>> this on a instrument from
>> 1982? The cert that came with it originally said: "no errors for
>> practical navigation" but down in
>> the lower right corner it said "RES: 0.02" which I would take to be a
>> resolution of 0.02 of a degree
>> i.e.; a little over a minuet of arc (0.016666) But I have seen certs on
>> sextants showing errors in
>> arc seconds. In practical terms how important is this?
>> Thanks,
>>        ~Greg
>>
>>
>> On 12/26/2013 03:55 PM, Greg wrote:
>> > Hi all,
>> >   forgive the bandwidth but is anyone here familiar with a sextant
>> > sold as the "Luna Sextant"
>> > by the apparently now defunct "Luna Trading Company, Matairie LA" I
>> > just bought it last week
>> > off of ebay from a guy in Georgia. The sextant appears in to be
>> > pristine condition no wear on
>> > the worm or the scale gear. I saw another one being sold by a
>> > Salvation Army group in Texas,
>> > but it was bid up too high for me. This one cost me $425. we have not
>> > had any clear view of
>> > the sky due to clouds to try a 'real' sight, then the holiday, but
>> > initial puttering with it shows that
>> > I can set the IE to zero, and if I sight on a distant house etc, and
>> > take a altitude, then return to
>> > 0 degrees the IE is still zero - (unlike my plastic Davis sextant).
>> > The seller threw in a book he had
>> > got with it called "Celestial Navigation" (C) 1989 by Tom Cunliffe The
>> > book has the previous
>> > owners name, FL address, and phone number but the phone is
>> > disconnected and I think this
>> > might have been purchased at an estate sale for speculation (?) Any
>> > Idea how good or bad this
>> > instrument is, and what I should expect for accuracy (on land for the
>> > moment)?
>> > Many thanks in advance,
>> > ~Greg
>> > 'Svenska Flicka'
>> >   Cat 28 #467
>> >
>>
>>
>> : http://fer3.com/arc/m2.aspx?i=125941
>>
>
>
> : http://fer3.com/arc/m2.aspx?i=125942
>
>
>
>

   

Reply