At 06:46 PM 6/30/01 +0100, you wrote:
>On Sat, 30 Jun 2001 07:26:58 -0400 rafeb ([EMAIL PROTECTED]) wrote:
>
>> I'm hoping (without evidence) that you're mistaken about
>> the swiveling LEDs. A 645 negative is approximately
>> 7,000 scan lines along the length of the strip (4.5 cm,
>> at 4000 dpi) and that would mean 21,000 mechanical
>> motions of the LED array (or 28,000 if you add the IR
>> channel.)
>>
>> I much prefer to believe they're switching the illuminant
>> colors electronically.
>
>Rafe, please don't take what I said as gospel - I'm relying on my raddled
>memory of a description I saw of the LS1000 mechanism many years ago, and
>may well have it *completely* wrong.
>
>What I *think* I recall is that the LED array is both switched
>electronically and moved mechanically at each scan line position, so the
>successive R, G & B exposures are made with R, G & B LED's and monochrome
>strip sensor 'looking at' precisely the same strip of film image 1 pixel
>high. IOW the LED array is positioned differently for each channel
>exposure, the relevant LED's turned on for the exposure duration, and then
>the cycle repeated for the next scan line, and so on.
<snip of ASCII art -- well done, BTW>
Ah, Tony, but I do take your word as gospel... <g>
Your word is surely as good as anyone else's around here.
I guess I was thinking that the LEDs are small enough
(and hopefully diffused somewhow) so that mechanical
re-positioning is not required.
I am sorely tempted, but I dare not open up my scanner
to investigate further.
I will admit that the noises emanating from this scanner
suggest mechanical goings-on that I'd rather not speculate
on. IOW, a coarse clicking/rattling/grating noise that
seems much too coarse to correspond to steps at 4000 dpi.
I've never heard another scanner (either film or
flatbed) make noises like that.
rafe b.
