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[filmscanners] Re: Black and white scans on LS4000 ED and otherissues
Hi Simon, Thanks for acknowledging that some things I say pan out in
the real world ;-)
The problems you are experiencing with the LS4000ED are:
1) LIGHT Source
2) LIGHT source
3) Light source
(repeat down the page).
The Nikon LED collimated light source doesn't ONLY make DDS (Dust, dirt,
and scratches) more visible, but also G (grain). Hence, my coining DDSG
as the short cut. WHY? Because the contrast is increased between the
grain edge and the "open space". There is a minimal antialiasing that
occurs even with the grain when a diffused source of light is used. It
is meaningless in terms of "sharpness" but it provides a buffer to
reduce aliasing. Any slight loss of this type that might occur can be
retrieved during USM anyway.
I'm sure Kennedy can explain this in much better terminology than I, but
the result is simply that collimated light increases the visibility of
these film "features" and the more the contrast and definition is to
begin at the transition of an edge (which is after all what determines
frequency) the more aliasing that takes place. With something like
"real" black and white where the grain is physical and opaque (not a
transparent dye cloud) this problem will be further emphasized.
This is also happening with color films with this LED light source, but
it is less objectionable (until you start using the USM and it rears its
ugly head more prominently).
This is just one reason why I promote scanners with diffused light
sources, and defocusing built into the optical path.
And, for the 10+14e time, (and this is not directed to you specifically,
Simon, as you probably know this), grain is not sharpness, grain is not
resolution, grain is an artifact, a mechanical/chemical film "feature"
it is not "the image" it is a building block of the photographic image.
If I could see the atomic structure of matter, I might be able to look
at my desk stapler and tell you it was made of assorted electrons,
neutrons, protons and electrical bonds between them, and I MIGHT even be
able to recognize those patterns as certain specific types of atoms, and
even molecules and mixtures of metal alloys, due to my worldly
experience, and yet still be unable to "see" its as a stapler. If I
want a stapler, being able to see atomic structure really doesn't get me
much closer to recognizing one.
If I am looking for a friend in a crowd, screening for "organic life
form" or even "human life form" is not that useful. Yes, yes, I know,
if I could read DNA sequences and knew theirs I could find them....
OK, now this is just getting silly ;-)
Simon Lamb wrote:
> Responses in the text below:
> Major A wrote:
>>>I tried scanning some Delta 100 black and white negs on a Nikon LS4000 ED
>>>and the quality was awful, using either Nikon Scan 3.1.3 or Vuescan. I
>>>tried scanning as monochrome, as colour and as colour positive and
>>>in Photoshop. In all cases the preview image looked fine but the actual
>>>showed tiny white spots all over the images.
>>I use an LS-30 and have the same problem. The little specks are dust
>>or similar defects on the negative. ICE doesn't work for silver-based
>>film list Delta 100. You would see the same thing on colour negative
>>if you turned ICE off, I think.
> I also use an LS-30 and do not see the problem as badly as with the LS4000,
> probably due to the reduced ppi resolution. However, using the Flextight
> Photo and the Sprintscan 120 on the same neg produced a much, much cleaner
> scan. I suspect the LED light source of the Nikon scanners, which is not
> shared by the Photo or SS120, might have a part to play here. I can
> certainly bear out Art Entlich's comments that dICE is less needed on other
> scanners because they do not pick up the dust and scratches as much as the
> Nikon scanners, although the scans are just as sharp.
> The problem is very much less on colour negative film (in my experience) and
> of course a small amount of dICE fixes any remaining issues with dust and
> scratches anyway.
>>The real problem I have with it is grain exaggeration. I can get much
>>less grainy scans from a paper print.
>>>I can't seems to get a good black and white scan at all. Can anyone tell
>>>how to get good black and white scans?
>>Nikons only support RGB readout, therefore using monochrome and/or
>>negative settings in the scanning software is always a lottery. I use
>>straight RGB scanning, then convert to grayscale and adjust the
>>look-up table in ImageMagick or GIMP (no M$ on my computer).
> I almost always use positive RGB settings to scan BW images, then invert and
> convert to greyscale either through desaturating or the channel mixer. On
> most scanners I have tried (must be about all of them by now!) this works
> fine (the best probably being on the SS120, although on that scanner I used
> RAW BW format and manipulated the raw file in PS for excellent results). I
> cannot get a good scan from the LS4000 ED though.
>>>When scanning colour slides (Provia 100F and Kodak EBX 100) the scans
>>>too much red in them. Is this a facet of this scanner?
>>Shouldn't be. The scanner has separate exposure times for the three
>>channels which can be set by the software. I have no idea what
>>Nikonscan, VueScan and friends do with the exposure. SANE lets you
>>select each of them separately, and offers both auto-exposure modes
>>supported by the scanner. With this method, you can play around until
>>you get perfect white balance. The response to the exposure times is
>>very much linear, so a little calculation can speed up the process
> As to the redness in the scans, just about every colour slide I scanned,
> mostly Provia and EBX, showed a tendency towards red and the blues also
> needed work. I guess calibrating the scanner and producing a profile would
> help here. Why don't manufacturers issue target calibration slides and a
> software routine with their scanners so that this can be done, as it is an
> important part of the colour managed workflow.
>>Also, SANE gives you a general multiplier, so that you can change all
>>exposures by the same factor and keep the white balance as it is. This
>>way you can make best use of the available dynamic range of the
>>scanner. Judgement is done with the histogram (Nikonscan & Co. might
>>have one as well, I wouldn't know...).
>>>When scanning a strip of slides (or negs) in the strip film adapter, the
>>>left edge of the preview image and scanned image is not straight, it bows
>>>at the centre and into the image area. Has anyone else seen this? It is
>>>annoying as I had to crop a part of the image when I didn't actually want
>>Oh. Have you checked that the mask in the film strip loader has a
>>straight edge? Since the light passes through the film pretty much at
>>a right angle, I wouldn't expect curling to have such an effect.
> The left edge on the film strip loader is not straight and I am sure I read
> somewhere on this list, or perhaps on the scanner forum on Imaging Resource,
> that others had this problem. Can anyone else verify this?
>>>Also, the preview in Nikon scan looks very clear whereas the actual
>>>completed scan image in the Nikon Scan window looks muddy and grainy, and
>>>you can see the white spots, that I mentioned above, on the image.
>>The opposite of SANE then...
>>>Any help, answers or opinions on these would be welcome.
>>Try SANE, it lets you select scanner options directly. Currently there
>>is no dust removal, but I'm working on it...
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