Acetate or Mylar when wet-mounting?

[Ari]

Hi,
I am preparing to do my first wet-mount scans on an Epson v750.
I will mount directly on the scanner glass, a few drops of Kami on the glass, film emulsion-side-down, a few more drops on the film, and cover it with a sheet of...
Mylar or Acetate?

I had heard that acetate could react with the Kami, that Mylar is the safer way to go.
Does anybody know for sure? Does it matter?

Lastly, is it that important to place the film emulsion-side-down on the scanner, or can it go either way?

Thanks in advance.

[mdm]

Wet mounting is a right pain in the rear. What works for me is to mount emulsion to the glass with base to the scanner and nothing over it at all. That makes it quicker than taping film onto the glass dry, and fixes most of the problems with scratches etc. I use blotting paper to soak up any excess fluid, it can be reused many times.

(I should clarify that this is with a betterscanning holder)

[Gem Singer]

Using Kami Fluid directly on the scanner glass could result in some of the fluid getting into the scanner mechanism below.

The V750 comes with an auxilliary glass tray for wet mounting. The tray has raised edges to contain the fluid.

I found that the ideal focus on my V750 is on the top surface of the wet mounting tray.

After using volatile Kami fluid for a while, I switched to using a sheet of ANR glass to hold the negative flat.

I'm scanning HP-5+ 4x5 and 5x7 sheet film. The film has an emulsion surface that is textured enough to prevent Newton's Rings when placed placed against a smooth glass surface.

The ANR glass is placed on top with it's textured side contacting the smooth base surface of the film. Reversing it later in Photoshop.

The auxiliary tray is too small an 8x10 negative.

BTW, there is a video on the AZTEC website that demonstrates the wet mounting technique.

[sanking]

Mylar is a brand name for polyester. Any good quality clear polyester of about 0.003" - 0.005" should work fine for fluid mounting. I would not use acetate.

Most of the instructions for professional flatbed scanners call for fluid mounting with the emulsion side facing the CCD , and of course these machines have auto-focus. Epson software gives the correct image orientation emulsion side up but you can mount emulsion side down and flip the image in PS. In theory the best way would be emulsion side down, but with the Epson V750, which does not auto-focus, the most important issue is to place the negative at the best plane of focus.

Sandy





Hi,
I am preparing to do my first wet-mount scans on an Epson v750.
I will mount directly on the scanner glass, a few drops of Kami on the glass, film emulsion-side-down, a few more drops on the film, and cover it with a sheet of...
Mylar or Acetate?

I had heard that acetate could react with the Kami, that Mylar is the safer way to go.
Does anybody know for sure? Does it matter?

Lastly, is it that important to place the film emulsion-side-down on the scanner, or can it go either way?

Thanks in advance.

[Ari]

Thanks, everyone.
I scanned using acetate, since the Mylar I bought had a lot of dust on it; no problems, but perhaps in the long run, it would be better to use Mylar.
I compared two scans I did: one with the BetterScanning holder, height-adjusted, dry; the second wet-mounted on the scanner bed with an acetate sheet over it.
For the dry scan, I chose Film with Film Holder in Epson Scan, and for the wet-mount, I chose Film with Film Area Guide.
I'm having trouble telling them apart at 100%, with regards to sharpness.

I'll post examples later.

The wet-mount seems like a little less work, and there are fewer surfaces to clean, so I'll go in that direction for now.

Thanks again.

[Ari]

Here is the original, uncropped photo:

http://i49.tinypic.com/our0ac.jpg


Ok, 100% crop.
First, the dry mounting:

http://i46.tinypic.com/cp652.jpg


And, next, the wet-mount scan:

http://i45.tinypic.com/35i88pu.jpg

There are differences in the overall levels, but sharpness looks about the same.

[Andrew O'Neill]

I tried wet scanning with my friends epson v750, and could not see a difference in sharpness. As Ari indicated, there was a slight difference in levels. Seems like a lot of fuss and bother for nothing. No?

[Ari]

...there was a slight difference in levels. Seems like a lot of fuss and bother for nothing. No?

Maybe, and maybe not.
What I'm starting to see is that the dry mount scans are contrastier, thus deeper shadows right out of the box.
The wet scans are of a softer contrast, and thus preserve more shadow detail.

So far, there is less fussing than with dry mounting, i.e., the tape, fingerprints, etc.
More later!

[Andrew O'Neill]

The wet scans are of a softer contrast, and thus preserve more shadow detail.

Tis why I scan in everything really flat. It's kind of like when I'm in the darkroom making a print. I always start off with a very flat print to see what the negative holds.

[Ari]

I would not use acetate.

Why not? Because of chemical interaction with the scanning fluid, or does it have undesirable optical properties inferior to those of Mylar?