----- Original Message -----
From: <EdHamrick@aol.com>
To: <filmscanners@halftone.co.uk>
Sent: Friday, May 04, 2001 7:55 PM
Subject: Re: filmscanners: VueScan Long Exposure Pass
> In a message dated 5/4/2001 11:06:17 AM EST, steve@gccl.fsbusiness.co.uk
> writes:
>
> > What about a slightly underexposed slide (this can produce a better
result
> > when projected). I assume the long exposure would help.
>
> VueScan already automatically lengthens the exposure to maximize
> the intensity of the scanned image without saturating the brightest
> pixels.
>
> However, the "long exposure pass" option did two passes, one with
> a properly exposed image and one with a significantly overexposed
> image (usually 6x). This saturates all pixels above 1/6 of the maximum
> intensity, and then these two passes were being combined.
>
> The problem with this is that overexposed pixels will bleed charge
> into adjacent pixels, and the amount of bleeding is unpredictable
> (and it's also directional sometimes, bleeding mainly to either the
> left or right).
>
> Regards,
> Ed Hamrick
>
OK ed I've coughed upo my $40 as Ican't get Siverfast to behave but I am
less than convinced that long exposure isn't a useful option.
I've redone my tests and you can see the results at (refresh if necessary) :
http://www.greenbank.themutual.net/artixscan4000_noise.htm
Strangely 8x with long exposure is much better than 8x (with the echo). I
tried 8x 4 times with similar results - I tried 8x with long exposure twice
with similar improved (no echo) results.
Is this a coincidence ? - seems unlikely to me.
Why does 8x work better with long exposure?
To be fair the noise levels are much better than Scan Wizard Pro or
Silverfast.
Steve