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From: Fred Hebard (no email)
Date: Mon Oct 04 2004 - 19:29:59 EDT
On Oct 4, 2004, at 6:08 PM, Alexandre Eremenko wrote:
> Dear Fred,
>
> By the way, your table shows pretty large variation of the index
> error from day to day. This seems surprising to me.
> Is this what it should be? Is this related to the air temperature?
>>
>> I started out with
>> inferior equipment to what you have,
>
> ?????? What do you mean? Cassens and Plath?
> Or Husun? In the table you sent me you seem to mention
> Cassens-Plath, if I understood your abbreviation "C+P" correctly,
> which everyone says is the top sextant of those still produced.
>
> When I was deciding what to buy as my first sextant, the choice
> was essentially between a 1945 "Gothic" Husun (full size
> brass frame,
> two scopes) and a "new" 1990 SNO-T which was cheaper.
> I think I decided for SNO-T for some sentimental reasons,
> as a former Soviet citizen, etc:-)
>
>
> Alex.
Alex,
The large variation in index error from day to day is associated with a
weak spring in the horizon mirror, I hope!
I started out with a $35 Davis sextant, then went to a Husun which had
a broken handle. I may have uncentered the index while trying to
remove the handle. In an effort to get a more powerful telescope, the
Husun's was 2.5x, and more accuracy, I then bought a _used_ Cassens and
Plath.
Although I have not examined one, I believe a Tamaya Spica would be the
top sextant of those produced today in the old non-communist countries,
from what I hear. Cassens & Plath are very accurate and precise, but
there are some failings with them which I have outlined previously;
others also have commented on some failings in their bubble horizon
attachment, in comparison to a C. Plath (note that C. Plath is a
different company from Cassens & Plath). The Cassens & Plath is good
enough, however! In sextants from the old communist block, the
Friburger and Sno sextants have good reputations, and from what I hear,
may be as good as the Tamaya and C+Ps. Thus I am not sure that the
Cassens & Plath is superior to your instrument, but I agree it would
not be noticeably inferior.
Many of us who do not speak Russian are leery of buying from Russia,
having heard some horror stories. It is difficult for us to assess the
honesty of the various dealers.
Fred
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