Apache-Talk @lexa.ru 

Inet-Admins @info.east.ru 

Filmscanners @halftone.co.uk 

Security-alerts @yandex-team.ru 

nginx-ru @sysoev.ru 




      :: Filmscanners
Filmscanners mailing list archive (filmscanners@halftone.co.uk)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[filmscanners] Re: Lack of contrast in the (raw) scans from VueScan ?

This is how Vuescan is designed to work - to NOT clip any highlights or
shadows, but to leave that for postprocessing in PS or other program where
you can examine the image more closely and determine what if any endpoint
clipping to do, and set your black and white point with much more accuracy.

On the Device tab be sure your selection for "Option types" is advanced -
that will give you the full controls.

On the Color tab you can experiment with Color balance, Black point and
White point, and the Brightness controls.


----- Original Message -----
From: "Sassan Hazeghi" <sassan@cup.hp.com>
To: <mlidaka@ameritech.net>
Sent: Sunday, April 28, 2002 12:55 AM
Subject: [filmscanners] Lack of contrast in the (raw) scans from VueScan ?

I have had a Nikon LS-30 scanner for over a year now and until
recently it was being used occasionally to scan images that I needed
to post to a web page or send via email. A couple of months ago,
though, I started looking into how to capture the "most" from my films
for archival purposes and was surprised by the initial results from
using VueScan (which I had hoped would give me more than the 8bit
pixel depth I am getting from NikonScan.)

I am using VueScan 7.5 (beta ?) and NikonScan 3.1.0, and the "default"
settings for VueScan generally produces images that are washed out and
lack in contrast.  This is particularly pronounced for B&W negatives
(TMY-400 & Tri-X) where the histograms for the raw scans show ~10
points less std deviation than the scans produced by the (default
settings for) NikonScan.  The lack of contrast is also present, though
not as pronounced, when comparing the scans for T400-CN (C-41 B&W
film) as well as color negatives or slides.  Are there any obvious
controls for VueScan that I need to be changing (other than the film type
& scan resolution -- I don't seem to be able to find a manual exposure
or Analog Gain control.)

I have placed the JPG form of the scan files from NikonScan, VueScan
and raw fladbed scans from 4x6 prints (from the local lab) of a couple
of Tri-X and one T400-CN negative under the attached URLs (sorry about
the large files) and would appreciate any insight into what I may be
doing wrong as well as the answer to any of the the listed
questions I have run into, in the course of this exercise.





And the questions ...

- What is the appropriate film (media) setting for T400-CN ("color
  negative" or "B&W negative") under either software ?

- Likewise, how does one disable "autoexposure" entirely (NikonScan
  allows changing the Analog Gain but this seems to be changing the bias
  to the autoexposure readout. )

- Can VueScan reliably/repeatably get 10bit raw readouts of a given
  pixel or are the extra two bits simply random values being read
  independent of the value of the pixel ?  I.e. Does a full resolution
  scan of Q60 produce a tiff file that matches that of LS-40 ?

- Related to the above tow back-to-back scans of the same image
  (without any change to the registration of the film) seem to always
  produce scan files that differ measurably, if not  significantly. I
  realize that compared to digital logic, CCD's can be more temperamental
  but I am wondering, if this is more noticeable in LS-30 compared
  to LS-40 or LS-4000 or they all use a similar CCD array ?

- If I need to switch to a more capable scanner for consistent
  "archival" scans, beyond the auto slide-feeder, does LS-4000
  offer real advantages over LS-40 ?  More specifically:
  - Does LS-4000 cope with Kodachrome any better than LS-40/30 ?
  - Is the digital ICE capability of the LS-30 and LS-40 comparable ?
  - Is the Firewire interface in LS-4000 noticeably faster than
    LS-40's USB ?

- On a different type of question, how does one view the (density/
  luminescence) histograms for two images side-by-side under PS 6.0 ?
  This seems to be a very basic and useful operation but it is not
  obvious how to display the histogram for the second image without
  closing the first one !

Unsubscribe by mail to listserver@halftone.co.uk, with 'unsubscribe
or 'unsubscribe filmscanners_digest' (as appropriate) in the message title
or body

Unsubscribe by mail to listserver@halftone.co.uk, with 'unsubscribe 
or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or 


Copyright © Lexa Software, 1996-2009.