You may try to use a good quality third party film holder like the ones provided by Betterscanning.com and even use anti newton glass to keep the film strip as flat as possible. Those film holders have several screws for proper focusing adjustment and it's very labour intensive to have all set to the proper height.
The Betterscanning holders aren't cheap but they provide a very ample fine focus adjustment and compared to the Epson holder they're much better. But there are still two problems: It's expensive, specially if you order it with the anti Newton glass plates. And because of the extra glass, there are some contrast loss due to reflexions. The second problem is that the Digital ICE infrared dust removal works very badly with the extra anti Newton rings glass. You mus have pristinely clean films to use the Betterscanning holder (and similar ones).
Too many air to glass interfaces decreases contrast and may add odd reflections. Usually the reflexions aren't a big problem. Below, that's what happens to a light ray when it hits a glass plate: dispersion and internal and external reflections making it bounce in and between other glass surfaces.
The additional dispersion is almost certain to make the Digital ICE to fail. You may check if it still work.
The dispersion effect is much higher with anti Newton glass because in fact, this kind of glass has one (or both) external surfaces etched to minimize the glass to film contact. The effect of this is the reduction of Newton rings.
|The internal reflectance at an air/glass interface for light rays from a point source in glass. Light rays incident at angles to normal at greater than the critical angle (here, 41° for glass to air) do not leave the material and are reflected at the glass/air interface. source: ASU|
What's fluid mounting (wet mounting) ?
It's when you use a fluid between the film strip and the glass to keep it "glued" to the glass to make it as flat as possible and also to remove one of the air to glass interfaces.
There are two main ways to do this. The first one is to use a dedicated fluid mount holder system, like the one Epson send with the V750. There are some clones on the market.
|Epson fluid mount for the V750|
It's basically a holder with a glass bottom and an alignment support with a printed grid.
The idea is to:
- Put some sort of fluid over the glass
- Place the negative over the fluid
- Allign it using the grid pattern
- Cover the film with a transparent mylar or polyester film. You need to apply some fluid over the film, between the film and the transparent film.
- Squeeze out any bubbles with a very soft cloth
- Place the holder over the scanned flatbed and scan
|Wet mount directly over the scanner glass|
Epson V700 at 2400 dpi