negative -> epson 4870, shiny side up or down?

[false_dmitrii]

This has been bugging me for a while. Epson recommends placing
negatives with their base (shiny?) side face down. But I've
occasionally seen people recommend the opposite. I wish I knew enough
about film and scanner technology to deduce it myself, but that's a
long way off at best. I still mix up the base and emulsion sides.
Has anyone figured out which side should *really* face down in the
4870, and why?

Hoping for enlightenment,
false_dmitrii

 

[Bill]

This has been bugging me for a while. Epson recommends placing
negatives with their base (shiny?) side face down. But I've
occasionally seen people recommend the opposite. I wish I knew enough
about film and scanner technology to deduce it myself, but that's a
long way off at best. I still mix up the base and emulsion sides.
Has anyone figured out which side should *really* face down in the
4870, and why?

Say that you used a light box to view negatives or slides. You would
have the shiny side up, correct?

Pretend the scanner sensor are your eyes and the scanner light is the
light box. Shiny side should be down, emulsion up.

 

[Leonard Evens]

false_dmitrii wrote:




Say that you used a light box to view negatives or slides. You would
have the shiny side up, correct?

Pretend the scanner sensor are your eyes and the scanner light is the
light box. Shiny side should be down, emulsion up.

Actually, Epson can do anything it wants about the orientation by
programming the firmware of the scanner appropriately. So the above
explanation, while plausible, is not the whole story. It seems to me
that the relevant fact is that a flatbed scanner is designed to come up
with the right orientation for an original document placed face down on
the scanner glass. The firmware in the scanner is designed with that in
mind. Of course, they could reverse it when the scanner is set to scan
film, but apparently they didn't feel it was worth the effort. Or,
maybe they had some other reason. So you also have to place the film
"face down". The "face" of the film is the side you view it from so as
to have proper orientation, which is the "shiny" side. So the shiny
side should be down and the emulsion up.

With b/w negative, it is usually not too hard to tell the difference
between the emulsion and base. The emulsion is really duller. This is
harder with color negative film and even harder with color slide film.
If you hold it at an angle, that may make it easier to see. Also, any
lettering on the film margin will probably be reversed if viewed from
the emulsion side. That is because the lettering is almost universally
placed to be right side up when viewed from the base side. (But I do
have some old Kodak color negatives in which the lettering is right side
up on the emulsion side.)

There is one additional question. Will you get a better scan if you
place the film emulsion side down? The image will be reversed, which
is why Epson tells you not to do that, but you can easily reverse it
either in the scanning software or in your photoeditor. Some people
claim to get better results this way. I've tried it both ways, and I
don't see an difference.

 

[Peter Brumby]

This has been bugging me for a while. Epson recommends placing
negatives with their base (shiny?) side face down. But I've
occasionally seen people recommend the opposite. I wish I knew enough
about film and scanner technology to deduce it myself, but that's a
long way off at best. I still mix up the base and emulsion sides.
Has anyone figured out which side should *really* face down in the
4870, and why?

As far as I can see there are three possible factors:-

1. Orientation. Base side down on a flatbed should give the correct
orientation, but if the other factors dictate emulsion side down, the mirror
image can usually be easily corrected in the scanning or post-processing
software.

2. Newton's rings - more likely with the glossy base in contact with the
glass.

3. Focus - if the base side is down the image (in the emulsion) will be
further away from the glass by the thickness of the base, which may or may
not be significant.

In the absence of any guidance on the matter from the maker of my scanner
(Microtek) I avoid issues 2 and 3 and scan emulsion side down, flipping the
image in Paintshop.

Peter

 

[Robert Feinman]

As far as I can see there are three possible factors:-

1. Orientation. Base side down on a flatbed should give the correct
orientation, but if the other factors dictate emulsion side down, the mirror
image can usually be easily corrected in the scanning or post-processing
software.

2. Newton's rings - more likely with the glossy base in contact with the
glass.

3. Focus - if the base side is down the image (in the emulsion) will be
further away from the glass by the thickness of the base, which may or may
not be significant.

In the absence of any guidance on the matter from the maker of my scanner
(Microtek) I avoid issues 2 and 3 and scan emulsion side down, flipping the
image in Paintshop.

Peter

I find that with medium format images the film can sag in the holder so
sometimes it is better to have the film curve up which is then countered
by gravity leading to an overall flatter piece of film.

 

[RSD99]

"Peter Brumby" posted:
"...
As far as I can see there are three possible factors:

1. Orientation.

2. Newton's rings

3. Focus
...."

Don't forget

4. You are scanning through the "film base" to get to the image.

In traditional photographic print making, the emulsion side of the film is
*****ALWAYS***** on the side of the final resulting image, and the image is
*****NEVER***** projected through the film base.

I do the same with scanning, and have not (yet) experienced problems with the first three
items. In fact, to me it seems stupid to scan *through* the film base ... just another
layer of "stuff" to cause problems!

 

[Ronald Bruck]

....

place the film emulsion side down? The image will be reversed, which
is why Epson tells you not to do that, but you can easily reverse it
either in the scanning software or in your photoeditor. Some people
claim to get better results this way. I've tried it both ways, and I
don't see an difference.

I don't see a difference either. But when the film is significantly
bowed, it will contact the glass one way, but not the other. On my
4870 I get definite Newton rings when this happens.

So I've taken to reversing Epson's recommendation and flipping the
picture in software.

--Ron Bruck

 

[Peter Brumby]

Don't forget

4. You are scanning through the "film base" to get to the image.

In traditional photographic print making, the emulsion side of the
film is *****ALWAYS***** on the side of the final resulting
image, and the image is *****NEVER***** projected through
the film base.

Agreed. Unless the base is 100% transparent, there will be some degree of
light scattering and hence degradation of image clarity.

Yet another reason to have the emulsion side down.

Peter

 

[false_dmitrii]

Agreed. Unless the base is 100% transparent, there will be some degree of
light scattering and hence degradation of image clarity.

Yet another reason to have the emulsion side down.

Peter

Thanks, all, for the informative replies. Unless I hear otherwise,
I'll start scanning emulsion side down, "shiny" side up, and see how
it comes out. I wonder why Epson favors the opposite placement? They
do recommend flipping the film to avoid "Newton's rings", though they
don't discuss the film actually coming into contact with the surface
(not common for 35mm negatives in the Epson adapter).

false_dmitrii

 

[Robert M]

it comes out. I wonder why Epson favors the opposite placement?

It's just because of the orientation of the final scan on monitor,
and it is the similar reason why in USA they must print the note on the
bag with fryed french fries that they are hot

Always scan with emulsion side down and correct the orientation with
software...
This is the rule...