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Doug,

Perhaps the subject which interests me most about sextants is how to
calibrate one.  More specifically, do you know of any place in the U.S.
that still does that?  I am referring to the sextant corrections one
finds in the box lid for uncorrectable errors, such as eccentricity of
the arc.

Thanks,

Fred Hebard

On Jan 30, 2004, at 8:14 PM, Joel Jacobs wrote:

> Hi Doug and All,
>
> As Doug suggested, I went to the archives between January and maybe
> April,
> and found a couple of threads in which I would liked to have
> participated.
> Coast Navigation and Prop walk. Prop walk I would have much to say
> about. I
> never did find Doug's reference. I will go back and look some more. But
> here's some of the memories the archives brought back.
>
> First, let's talk a little bit about the MS 733 Spica since I was in
> on its
> design, and represented Tamaya & Co's interests in the U.S. from 1972
> to
> Nov, 1978 when I sold Nautech Maritime Corporation to Coast Navigation
> which
> by then had moved to Annapolis. I had seen the handwriting on the wall
> with
> SATNAV and it was time to fulfill a life long ambition and implemented
> a
> plan I'd had for some time. So my wife and I  went off on six years of
> ocean
> cruising, mostly in the Eastern Caribbean, but also up to New England,
> the
> East coast of the U.S., and then back to the Caribbean in our Bob Perry
> designed ketch, Bagheera.
>
> But back to Tamaya. We're still in touch with the Hattori's who were
> the
> owners of Tamaya until maybe the mid 80's. BTW, we were the guests of
> honor
> to celebrate the ground breaking of a new factory in the Tokyo area
> around
> 1977. They visited us in Ft. Lauderdale as recently as 1985 which is
> not so
> recent. And Yasuo gifted me with the printing version of the NC 77,
> maybe
> the NC 2000, and two of the new plastic cases. At least once each
> year, we
> communicate, and if they travel to the States we talk by phone.
>
> Earlier this past year, I sold a very special Tamaya-Nautech MS 733 to
> a
> retired Navy CAPT who is the lead in certifying Aegis DD's prior to
> turnover
> to our Navy. That sextant had no markings so that I could use it as a
> test
> instrument to try and secure a Navy contract. Even though the lab and
> ship
> it was sent to gave it exceptional marks, it didn't happen because of
> "Buy
> America".  David White & Co. of Milwaukee got the contract for 250 MK
> III
> sextants. Even in those days sextant sales were no big deal. What was
> a big
> deal was the contract that Nautech received to supply the Navy,
> Airforce,
> and maybe the USCG with NC-2 navigation computers, two each for every
> navigator so as to assure redundancy. The USAF, had 5000 naviguessers
> at the
> time. I have my personal MS 733 in storage where its been for many
> years.
> And I mentioned using my NC-2 in one of my ramblings.
>
> Anyhow, the Polaroid filter that Tamaya had available as standard for
> MS 733
> and MS 833 Jupiter, was a cap that fit on the ocular lens of the scope.
> There was another polarizing filter that was quite deep in cross
> section
> that was used on some less expensive sextants, but could have been
> fitted to
> a Spica. It had an inner and outer ring, and they could be adjusted to
> increase or decrease the effect of the Polirizer. Is that what you have
> Doug?
>
> I've been on the Binnacle List since May 2003, and can no longer
> actively
> participate in my various Navy related activities, I went back into the
> sextant business after a 28 year absence. I'm happy to report I'm an
> Astra
> III B dealer, and was pleased to hear the ships are using their
> discretionary funds to buy some sextants. Doug didn't say if these
> were Navy
> types, but I hope they were. Reading that, I checked, and don't see
> where
> Celestaire offers a Polarizing filter. Maybe something you should ask
> Ken
> Gebhart about. But if you need sextants, NEW or PRE-OWNED see me not
> Ken.
> He's a rich man today having been in the sextant business continuously
> longer than anyone. ;-)
>
> Sorry if I bored you,
>
> Joel Jacobs
>
> ----- Original Message -----
> From: "Royer, Doug" 
> To: 
> Sent: Friday, January 30, 2004 6:53 PM
> Subject: Re: Night shots useing refected light
>
>
>> Joel,my personal sextant is a Tamaya MS-733 and it always goes to sea
>> with
>> me.I ordered and picked it up in Japan many years ago.It has some
> customised
>> features that a person can get only if ordered and bought in
>> Japan.Look in
>> the archives,early to mid '03,as I discribed it and the extras I got.
>> Some of the Astra IIIB sextants may also have polarizing shades.I've
>> used
>> those while on duty and  recall doing this very thing with one.
>> Speaking of the Astra,I was in a local equipment store a few days ago
>> when
> a
>> Lt. and a Master Chief came in and bought 4 brand new Astras from the
>> owner.I asked the M.C. about it and he stated they were being placed
>> on 2
>> Navy ships getting ready to deploy for training.$480.00 each.
>>
>> -----Original Message-----
>> From: Navigation Mailing List
>> [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM]On Behalf Of Joel Jacobs
>> Sent: Friday, January 30, 2004 15:16
>> To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM
>> Subject: Re: Night shots useing refected light
>>
>>
>> Doug,
>>
>> You may have said earlier which sextant you're using with Polarizing
> shades.
>> If you did, I missed it?  I've seen some Japanese sextants fitted with
> them,
>> but know of no others. To the best of my recollection, Tamaya never
> offered
>> them, at least until 1979.
>>
>> Joel Jacobs
>> ----- Original Message -----
>> From: "Royer, Doug" 
>> To: 
>> Sent: Friday, January 30, 2004 3:55 PM
>> Subject: Night shots useing refected light
>>
>>
>>> Peter,I can't explain what causes the phenominon you described.You
>>> are
>> right
>>> that the true horizon doesn't match the reflection.I've never done
>>> one
>> from
>>> a small vessel so I can't comment on if the height of eye has
>>> anything
> to
>> do
>>> with it either.It does appear mostly on those nights when there is
> little
>>> breeze,seas are calm with clear atmospheric conditions.
>>> On nights with the light from a 3/4 to full moon one can make out
>>> the
>>> differance between the sea and sky even when the moon's altitude is
> fairly
>>> high and quite a large number of degrees in arc either side of the
> moon's
>>> azimuth.As the moon gets closer and closer to the horizon(setting and
>>> opposite when riseing)the reflected line of light gets more and more
>> intense
>>> untill the moon's light is refracted enough and the white light
>>> turns to
>>> orange.
>>> Useing the polarizing shade,sometimes useing both the horizon and
>>> index
>>> polarizing shade or a combination of all the shades if both the
>>> light of
>> the
>>> moon and the reflected light is strong,helps in seeing the black line
> you
>>> mentioned.
>

   

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