Re: filmscanners: Nikon 8000 ED or Polaroid Sprintscan 120 ??

[Arthur Entlich <artistic@ampsc.com>]

Dicky wrote:


> It all depends on the purpose for which the scanner was purchased.
> High end drum scanners such as the Hell, Dainippon or Crosfield, remove
> scratches by mounting the original in a glycerine solution. Dust is removed
> at the picture editing stage, post scanning.
> The reason for this system is that scanner productivity is the key to system
> output levels and therefore anything that slows down output is avoided.
> The amateur, on the other hand, has rarely such a need and usually likes
> their equipment to embrace as many functions as possible in a single
> product.
> This is seen as good value for money, which I would suggest is the case.
> He is not likely to be selling his scans for profit and therefore has little
> need for high output of digitised images and is also not likely to have any
> time deadlines to meet.
> 
> Richard Corbett

I'm really glad you got into this with your reply, because it was 
exactly what I wanted to say.  At one point, I was in conversations with 
Kodak concerning the possibilities of making some mural sized images 
from 35mm frames (mainly Kodachrome 64/25).  After gritting their teeth 
at me, they told me of some labs using "wet gates" as are used in making 
reproductions for 35mm commercial movie releases when they want to avoid 
as much dirt, dust and scratches in the "prints" (as in film copies from 
negs, not as in photographic prints).  These systems put the film 
through a pre-cleaning wash and then make their enlargements in a 
viscose solution between glass, which eliminates surface scratches from 
being visible, and also surface to air reflection which can soften edges 
due to the nature of light and optics.

When David mentioned that drum scanner operators weren't interested in 
dust reduction options, I too had similar thoughts to your own.   The 
d.ICE or FARE systems are rather ingenious in their use of infrared 
information.  In spite of what our friend from the developers of ICE, 
their magic does soften the results, and this is with good reason.  If 
you have even noticed, there is a little red line on most lens barrels, 
which is off center from the focus line.  The reason for this line is to 
show the differences in focus point between visible white light and 
infra red, for people who are using infrared films.  One makes the 
focusing using the white light image in the viewfinder, and then moves 
the lens barrel the amount of the offset this red line provides.  The 
image now looks out of focus in the viewfinder, but is in focus for 
infrared, which has a different wavelength than white light.

Actually, to go one step further, the focal point from red, green and 
blue light are all different.  If you had a very precision, very narrow 
depth-of-field optics and you were to photograph an image through three 
different filters, (red, green and blue) you would find each focuses at 
a slightly different point.  This might even explain why the three color 
separations made in CCD scanners are not always equally sharp.

Since, as I understand it, d.ICE uses the infrared image as one 
component in the final image (even if it is subtractive in nature) the 
fact that it is likely out of focus probably causes a softening of the 
whole image, however slight.  This is not to "slight" the genius behind 
the process, but unless there is some way to refocus the infrared 
channel, (which might cause other problems during the correction 
process, like make the edges of defects show up more than they wish) I 
would expect a certain amount of softening in the image when d.ICE was 
applied.