This is the scanner you need, I have had this since 2004 & it still gives extremely good results both normal scanning & negative & or slides.
You take off the white covering that's over the underside of the lid. It comes (should do) with loads different of negative holders.
if you're lucky you might get one with all the negative holders.
This one is from America but just to show you how cheap you might pick one up for.
http://www.ebay.co.uk/itm/Epson-Perfection-3200-PHOTO-Flatbed-Scanner-/121514252405
It has a Dmax of 3.4, very good for shadow detail. Don't be put off by its age I have read reviews of up to date scanners & some are still being judged against this one.
There is a newer version the 4490 but not much better & both are not made any more.
But I have used mine consistently for the years I have owned it & not once has it let me down.
here's the Epson old page with a pdf link to the data sheet.
http://www.epson.com/cgi-bin/Store/consumer/consDetail.jsp?oid=27766185
If you do find one for sale second hand & are using Windows 7 then go here for advice on the driver.
http://www.softwarecandy.com/shop/f...fection-3200-photo-work-with-64-bit-windows-7
I have used this Windows 7 get around without any issues whatsoever.
If you are a Mac user this mat help,
http://download.cnet.com/SilverFast-Ai-EPSON-Perfection-3200-Mac/3000-2118_4-34681.html
but I cannot confirm its usefulness.
If you haven't already solved your scanner requirement I highly recommend checking the 3200 or 4490 they are still highly regarded & of course very very cheap now.
Another review,
http://ixbtlabs.com/articles2/epson3200/
Blimey just spotted this absolute bargain with all the neg holders, plus it's the newer 4490
http://www.ebay.co.uk/itm/Epson-Perfection-4490-PHOTO-Flatbed-Scanner/291320128654?_trksid=p2047675.c100005.m1851&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=28111&meid=f07b4014f84d487da67dfb07c392dd28&pid=100005&prg=11472&rk=1&rkt=6&sd=231417999365&rt=nc
Hope this (might) help(s)...