Epson V750 Question

[sanking]

The most effective mounting station I have seen is the one by Better Scanning.

http://www.betterscanning.com/

With this unit there is a mechanism for adjusting the holder to the right distance from the platen glass. The negative is wet mounted to the underside (side facing the CCD) of the glass, emulsion facing down. The AN side of the glas faces up, toward the light. Note that with this method the negative is spaced above the glass of the scanner, usually about 0.5 - 1.0 mm, not in contact with it.

I tested all kinds of systems with my Epson 4990 and this method IMO gave the best
results.

Sandy King

My own tests showed that I could achieve higher quality by not using the Epson wet mounting holder, in part because the light passes through the lower surface of the wet mount tray and then through the upper surface of the scanner bed, multiplying the number of times refraction is introduced.

[timbo10ca]

On my recent trip to California, I had an opportunity to compare my own fluid mount results against those of a proponent of dry scans with a diffusion filter, and I was surprised to discover the quality of his scans exceeded my own wet-mounted results.

His approach was to place the film in an IMACON holder on top of the EPSON wet mount tray, and then to place a pair of metal spacers on top of that (approximately 1/16 of an inch) and then a piece of diffuse Mylar on top of that. The results were very good, and much easier than wet mounting.

Still, we both thought that it might be a case where I had yet to truly optimize the height of the film on my scanner. So when I returned to Idaho, I tried a sandwich of plex.

The sandwich was placed directly on the scanner bed in this order, fluid, 1/8 plex, fluid, 1/16 plex, fluid, film, fluid, Mylar, diffuse Mylar. Lo and behold, the results proved better than the dry mounted method, though consuming more fluid.

The FILM HOLDER option was clicked to engage the higher resolution lens. I have yet to see if I can find a single piece of plex that equals the combination of the 1/8 and 1/16 to simplify matters.

But, for comparison, I've attached the two files, which, like the previous samples, represent a fingernail sized portion of a 4x5 transparency.

If the plex is degrading the scan, it sure doesn't show up here.

As for disc space, scanning at 6400 spi, consider that a 4x5 has to be scanned in two passes, each totaling about 2.5 gigs. Each of those is then downsized to 3200spi, and combined in PS to a single file, which is over a gig in size. To work on that file easily, I use the Layer Transfer Method.

What is "diffuse Mylar", and could you please explain the "layer transfer method" for photoshop?

I am trying to figure out a workflow for this machine that will give me the best possible results but the files are so huge they completely bog my computer down. Any editing in Photoshop takes all day, and ACDsee can't even seem to open the files if they're larger than 500Mb.

I'm not sure what you mean when you say that there must be 2 passes at 6400dpi (2.5 gig each, totaling 5 gig?). How do you downsize each pass and combine them? Is this done automatically? Do you have set it to make multiple passes? Why would I want to do this, and make the files even larger and unmanageable? Are you using 24bit RGB or 48bit? When I set my dpi to 6400 and use 24bit RGB for a 4x5 transparency, it gives me a single 2 Gb file. Then I open it in PS and downres it to 3200dpi, which is a 500Mb file. Do I need a faster motherboard (I have an AMD Athlon 64 X2 dual core 3800+), a better video card with onboard memory (mine is an Nvidia Geforce 7600 GT), or simply more RAM? How much RAM is needed for PS-ing these kinds of files? I can't seem to do much with a 500Mb file, but 110 Mb files are pretty manageable (scans from my 35mm film scanner). I'm wondering what the minimum file size I can get away with for MF (6x6), 4x5 and 5x7 film if my maximum enlargement will be 16x20.
Thanks,
Tim

[PenGun]

You need to find out the printer's hardware DPI and print to that. An Epson usually prints at 360 so 20" needs 7200 dots/pixels.