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From: Fred Hebard (no email)
Date: Fri Apr 28 2006 - 08:54:01 EDT
George,
The pictures on eBay are down-sampled. A full 3-5 Megapixel shot of
the arc, about 1-3 Megabytes of storage --too large for eBay-- should
be magnifiable enough to show the entire arc at the desired resolution.
Fred
On Apr 28, 2006, at 4:37 AM, George Huxtable wrote:
> Thanks to several list members who responded to my question about
> buying a sextant on ebay, with helpful suggestions.
>
>> My experience shows up the problems that can occur when you buy
>> something as finicky as a sextant, sight unseen, at auction. Will I
>> be tempted to try again? Probably, yes. What more can I do to avoid
>> another disappointment? I have no idea. Perhaps others, with
>> more experience of these matters, can offer suggestions.
>
> Such as Fred Hebard who wrote-
>
> "As Robert Gainer said. The other thing to do is ask the seller to
> email pictures to you. Most people should have or have a friend with
> a digital camera with enough resolution to show all the arc
> divisions. Of course you would need two pictures to avoid the index
> arm obscuring. Not everybody will have the skill to take a usable
> picture, but...."
>
> ====================
>
> Well, that ebay listing showed several photos, rather good ones.
> One showed the complete sextant with its arc, but the divisions of
> a Vernier sextant are so fine (at one-sixth of a degree) that you
> couldn't expect them to show up on such a picture. And such
> markings, on a highly reflective silver surface, are hard to
> photograph at the best of times. But there was a photo of a small part
> of the arc, taken close up, which did indeed show the divisions of
> the arc rather clearly, and satisfied me that all was well.
> Needless to say, the part of the arc that was pictured was NOT the
> section in which the divisions had been polished away! You live
> and learn, I suppose...
>
> So I'm still unsure what more I could have done to ensure I was
> getting a useful instrument. In many cases, a seller will plead
> ignorance about the technical details, which could make matters
> worse. In my transaction, I was dealing with someone who was, or had
> been, a professional navigator, and should have known better.
>
> I am apprehensive, now, about further ebay transactions; but I may
> get tempted again.
>
> George,
>
> ================
>
> contact George Huxtable at
> or at +44 1865 820222 (from UK, 01865 820222)
> or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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