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Brad,

> Has anyone ever matched the results published on their certificate from a
> calibration facility while using star to star distances?  Open call:
> Anyone?

Exactly the same challenge was posted on this list more than 10 years ago
(by Frank, if I remember correctly).
To my knowledge nobody on this list ever claimed that s/he could do this.

Alex.



> Brad
> On Dec 17, 2013 2:44 PM, "G Becker"  wrote:
>
>> ------------------------------
>>
>> I agree. When shooting Polaris in the daylight (not with a sextant) it
>> reduces to a distinct tiny white pinpoint, it disappears behind the
>> crosshairs.
>>
>>
>>
>> -----Original Message-----
>> *From:* NavList@fer3.com [mailto:NavList@fer3.com] *On Behalf Of *Peter
>> Monta
>> *Sent:* Tuesday, December 17, 2013 2:10 PM
>> *To:* george{at}gwbeckerpls.com
>> *Subject:* [NavList] Re: Sextant calibration
>>
>>
>>  ------------------------------
>>
>> Hi Brad,
>>
>> Rather than distinct points, stars are fuzzy blobs.
>>
>>
>>
>> It might help to illuminate the entire field with some background
>> light---that way the overall contrast of the scene would be reduced, so
>> that the eye would see just the bright cores of the stars against a grey
>> background.  Start with no light, acquire the blobs in the field of
>> view,
>> then gradually turn up the light source until the stars are maximally
>> pointlike, but not so much that they're not easily trackable by eye as
>> the
>> sextant is swung and adjusted.
>>
>> The few times I've looked at Venus during the day with binoculars, I've
>> been struck with how pointlike it seems against the blue sky.
>>
>>
>>
>> I have some camera images of star-star sights---they don't show the
>> "fuzzy
>> blobs" problem provided the exposure doesn't saturate the stars.  At
>> some
>> point I hope to finish the job of estimating my sextant's arc error
>> using
>> these images.
>>
>> Cheers,
>> Peter
>>
>> : http://fer3.com/arc/m2.aspx?i=125795
>>
>> : http://fer3.com/arc/m2.aspx?i=125796
>>
>
>
> : http://fer3.com/arc/m2.aspx?i=125798
>
>
>
>

   

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