Poor scanned color problem

Archived from groups: alt.comp.periphs.scanner (More info?)

I've been struggling to fully understand the poor color representation of my
scanned and later printed color photos. After looking at the printer end of
the process I'm now looking at the scanner. I recently scanned genuine
Pantone color samples
of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
analyze the samples on its cymk sliders. The result for the cyan sample was
c-79% m- 21% y - 8% k- 0%.
The other colors had similar "contamination". Am I right in thinking that my
inexpensive 8 year old Epson needs to be replaced?
10 answers Last reply
More about poor scanned color problem
  1. Archived from groups: alt.comp.periphs.scanner (More info?)

    "josh" <josqb@cinci.rr.com> wrote in message
    news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > I've been struggling to fully understand the poor color representation of
    my
    > scanned and later printed color photos. After looking at the printer end
    of
    > the process I'm now looking at the scanner. I recently scanned genuine
    > Pantone color samples
    > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > analyze the samples on its cymk sliders. The result for the cyan sample
    was
    > c-79% m- 21% y - 8% k- 0%.
    > The other colors had similar "contamination". Am I right in thinking that
    my
    > inexpensive 8 year old Epson needs to be replaced?
    >
    Not necessarily.
    Scanners do not produce perfect copies.

    This is largely a color management problem.
    Which I am not qualified to speak upon.

    Scanner lamps do lose color temperature over time and use.
    Borrow another scanner from a friend and see if you get better results.

    quote:
    The other colors had similar "contamination".

    Have you tried to create pure sample color patches with Photoshop?
    Then print at the best quality and on the best glossy photo paper.
    Then scan those prints.

    Here are two TIFF test scans to download. One is Kodak Gray and Color
    patches, the other is Macbeth ColorChecker Chart. Both of these scans were
    done with an AcerScan 620ST scanner.
    http://www.carlmcmillan.com/Test_images.htm

    One image is 2,112KB the other image is 2,887KB as reported by Windows
    Explorer. Your mileage may vary.<g>

    --
    CSM1
    http://www.carlmcmillan.com
    --
  2. Archived from groups: alt.comp.periphs.scanner (More info?)

    On Fri, 11 Jun 2004 11:59:32 GMT, "josh" <josqb@cinci.rr.com> wrote:

    >I've been struggling to fully understand the poor color representation of my
    >scanned and later printed color photos. After looking at the printer end of
    >the process I'm now looking at the scanner. I recently scanned genuine
    >Pantone color samples
    >of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    >analyze the samples on its cymk sliders. The result for the cyan sample was
    >c-79% m- 21% y - 8% k- 0%.
    >The other colors had similar "contamination". Am I right in thinking that my
    >inexpensive 8 year old Epson needs to be replaced?
    >

    Can't you just adjust the colour balance (or whatever epson calls it)
    in the driver config? I think even new consumer scanners will be a
    little bit off on colour sensitivity, but you can usually compensate
    for it.
    ---------------------------------------------

    MCheu
  3. Archived from groups: alt.comp.periphs.scanner (More info?)

    Thank you Carl for considering my problem. I did what you suggested
    regarding the use of photoshop to produce pure cmyk color swatches. Printed
    them out and then scanned them back in. The results were no better. The
    scanned so-called pure colors each show very noticeable mounts of the other
    two cmy components.

    Josh Page

    "CSM1" <nomoremail@nomail.com> wrote in message
    news:Yqlyc.4126$on.1843@newssvr24.news.prodigy.com...
    > "josh" <josqb@cinci.rr.com> wrote in message
    > news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > > I've been struggling to fully understand the poor color representation
    of
    > my
    > > scanned and later printed color photos. After looking at the printer end
    > of
    > > the process I'm now looking at the scanner. I recently scanned genuine
    > > Pantone color samples
    > > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > > analyze the samples on its cymk sliders. The result for the cyan sample
    > was
    > > c-79% m- 21% y - 8% k- 0%.
    > > The other colors had similar "contamination". Am I right in thinking
    that
    > my
    > > inexpensive 8 year old Epson needs to be replaced?
    > >
    > Not necessarily.
    > Scanners do not produce perfect copies.
    >
    > This is largely a color management problem.
    > Which I am not qualified to speak upon.
    >
    > Scanner lamps do lose color temperature over time and use.
    > Borrow another scanner from a friend and see if you get better results.
    >
    > quote:
    > The other colors had similar "contamination".
    >
    > Have you tried to create pure sample color patches with Photoshop?
    > Then print at the best quality and on the best glossy photo paper.
    > Then scan those prints.
    >
    > Here are two TIFF test scans to download. One is Kodak Gray and Color
    > patches, the other is Macbeth ColorChecker Chart. Both of these scans were
    > done with an AcerScan 620ST scanner.
    > http://www.carlmcmillan.com/Test_images.htm
    >
    > One image is 2,112KB the other image is 2,887KB as reported by Windows
    > Explorer. Your mileage may vary.<g>
    >
    > --
    > CSM1
    > http://www.carlmcmillan.com
    > --
    >
    >
  4. Archived from groups: alt.comp.periphs.scanner (More info?)

    Thanks for your comment. I presume you are referring to the adjustment
    options offered in the Twain interface. I had played with saturation before,
    but at your suggestion I tried tone correction, gamma and exposure. Nothing
    seemed to help. My scanner when presented with a Pantone pure magenta color
    swatch seems to see a significant cyan component and the other colors are
    similarly misinterpreted.

    Josh Page


    "MCheu" <mpcheu@yahoo.com> wrote in message
    news:qarkc0tsogl5n8luq692act59tr7v7nn04@4ax.com...
    > On Fri, 11 Jun 2004 11:59:32 GMT, "josh" <josqb@cinci.rr.com> wrote:
    >
    > >I've been struggling to fully understand the poor color representation of
    my
    > >scanned and later printed color photos. After looking at the printer end
    of
    > >the process I'm now looking at the scanner. I recently scanned genuine
    > >Pantone color samples
    > >of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > >analyze the samples on its cymk sliders. The result for the cyan sample
    was
    > >c-79% m- 21% y - 8% k- 0%.
    > >The other colors had similar "contamination". Am I right in thinking that
    my
    > >inexpensive 8 year old Epson needs to be replaced?
    > >
    >
    > Can't you just adjust the colour balance (or whatever epson calls it)
    > in the driver config? I think even new consumer scanners will be a
    > little bit off on colour sensitivity, but you can usually compensate
    > for it.
    > ---------------------------------------------
    >
    > MCheu
  5. Archived from groups: alt.comp.periphs.scanner (More info?)

    You are apparently just beginning to find out why soooo many people talk soooo da*# much
    about "Color Management."

    First, a couple of random thoughts about your posting, and predicament. Some of the things
    you need to consider are

    (1) HOW are you getting your CYMK measurement(s). All scanners ever made work natively
    (internally) in RGB. If you are loading the image into PhotoShop (or any other image
    editing program) and measuring the patches with the eye-dropper, WHAT are the settings in
    PhotoShop for the RGB --> CYMK conversion? Note that there essentially are an INFINITE
    VARIETY of these conversion factors available for this translation in PhotoShop,
    PhotoPaint, or other image editing program.

    (2) OK ... you've just gone to the time and expense of purchasing some Pantone color
    chips. You get a 'Very Good' for effort, but you have NOT gotten the right thing to
    analyze your situation. Why? Several reasons.

    First:
    There is always very significant "color contamination" in any and all printing inks, and
    Pantone color chips are made with printing inks. What you describe is fairly normal for a
    Cyan (printing) ink.

    Second:
    The Pantone Color Chips are not designed to be used for "calibration" applications. You
    need something that is. That would probably (best case) be a calibrated IT8 target. They
    are *expensive,* but available from several vendors.

    A usable solution might be getting something like a Kodak Q13 Grayscale / Color Patch
    set. They are *not* calibration / analytical grade, but they work pretty well for getting
    you into the ball-park. Cost would be about $20 ... and they are available form some of
    the larger photography suppliers ... for example, I *think* I've seen them at B&H. Another
    option would be to get a Gretag-Macbeth Color Checker, which is often used in the
    photography field, and is pretty consistent. Cost would be something like $70 ... and they
    are available form some of the larger photography suppliers. The difficulty with both the
    Q13 and The Color Checker is getting accurate numbers for what they *should* read.

    Note that recently there has been a rather long (and very interesting) discussion of the
    use of exactly these color "standards" in the Color Theory list hosted by Dan Margulis.
    Incidentally ... any of his books are well worth reading.

    http://groups.yahoo.com/group/colortheory/

    As a point of reference, I just scanned the color patches on one of my Kodak Q13 Color
    Patch targets. Here are the measurements in RGB ... I'm not including measurements in CYMK
    because my conversion setup is probably quite different than yours.

    Numbers are on the PhotoShop 0-255 scale.

    Cyan Patch
    R = 41
    G = 159
    B = 200
    G = 128

    Magenta Patch
    R = 211
    G = 35
    B = 107
    G = 96

    Yellow Patch
    R = 238
    G = 215
    B = 68
    G = 206

    Additionally ... you asked:
    "... Am I right in thinking that my inexpensive 8 year old Epson needs to be replaced?
    ...."

    I just replaced my old scanner with an Epson 4870 PRO ... and yes, (IMHO) it really *is*
    worth it.


    "josh" <josqb@cinci.rr.com> wrote in message
    news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > I've been struggling to fully understand the poor color representation of my
    > scanned and later printed color photos. After looking at the printer end of
    > the process I'm now looking at the scanner. I recently scanned genuine
    > Pantone color samples
    > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > analyze the samples on its cymk sliders. The result for the cyan sample was
    > c-79% m- 21% y - 8% k- 0%.
    > The other colors had similar "contamination". Am I right in thinking that my
    > inexpensive 8 year old Epson needs to be replaced?
    >
    >
  6. Archived from groups: alt.comp.periphs.scanner (More info?)

    To RSD99 my sincere thanks for your helpful posting.
    The one part of the calibration process I'm still unclear about is which
    knobs to turn to make an adjustment. I had been focusing on the Twain
    interface, but you seem to be suggesting the settings in PhotoShop for the
    RGB --> CYMK conversion.....is that correct?
    Josh Page

    "RSD99" <rsdwla.NOSPAM@gte.net> wrote in message
    news:oPKyc.14683$H65.5683@nwrddc02.gnilink.net...
    > You are apparently just beginning to find out why soooo many people talk
    soooo da*# much
    > about "Color Management."
    >
    > First, a couple of random thoughts about your posting, and predicament.
    Some of the things
    > you need to consider are
    >
    > (1) HOW are you getting your CYMK measurement(s). All scanners ever made
    work natively
    > (internally) in RGB. If you are loading the image into PhotoShop (or any
    other image
    > editing program) and measuring the patches with the eye-dropper, WHAT are
    the settings in
    > PhotoShop for the RGB --> CYMK conversion? Note that there essentially are
    an INFINITE
    > VARIETY of these conversion factors available for this translation in
    PhotoShop,
    > PhotoPaint, or other image editing program.
    >
    > (2) OK ... you've just gone to the time and expense of purchasing some
    Pantone color
    > chips. You get a 'Very Good' for effort, but you have NOT gotten the right
    thing to
    > analyze your situation. Why? Several reasons.
    >
    > First:
    > There is always very significant "color contamination" in any and all
    printing inks, and
    > Pantone color chips are made with printing inks. What you describe is
    fairly normal for a
    > Cyan (printing) ink.
    >
    > Second:
    > The Pantone Color Chips are not designed to be used for "calibration"
    applications. You
    > need something that is. That would probably (best case) be a calibrated
    IT8 target. They
    > are *expensive,* but available from several vendors.
    >
    > A usable solution might be getting something like a Kodak Q13 Grayscale /
    Color Patch
    > set. They are *not* calibration / analytical grade, but they work pretty
    well for getting
    > you into the ball-park. Cost would be about $20 ... and they are available
    form some of
    > the larger photography suppliers ... for example, I *think* I've seen them
    at B&H. Another
    > option would be to get a Gretag-Macbeth Color Checker, which is often used
    in the
    > photography field, and is pretty consistent. Cost would be something like
    $70 ... and they
    > are available form some of the larger photography suppliers. The
    difficulty with both the
    > Q13 and The Color Checker is getting accurate numbers for what they
    *should* read.
    >
    > Note that recently there has been a rather long (and very interesting)
    discussion of the
    > use of exactly these color "standards" in the Color Theory list hosted by
    Dan Margulis.
    > Incidentally ... any of his books are well worth reading.
    >
    > http://groups.yahoo.com/group/colortheory/
    >
    > As a point of reference, I just scanned the color patches on one of my
    Kodak Q13 Color
    > Patch targets. Here are the measurements in RGB ... I'm not including
    measurements in CYMK
    > because my conversion setup is probably quite different than yours.
    >
    > Numbers are on the PhotoShop 0-255 scale.
    >
    > Cyan Patch
    > R = 41
    > G = 159
    > B = 200
    > G = 128
    >
    > Magenta Patch
    > R = 211
    > G = 35
    > B = 107
    > G = 96
    >
    > Yellow Patch
    > R = 238
    > G = 215
    > B = 68
    > G = 206
    >
    > Additionally ... you asked:
    > "... Am I right in thinking that my inexpensive 8 year old Epson needs to
    be replaced?
    > ..."
    >
    > I just replaced my old scanner with an Epson 4870 PRO ... and yes, (IMHO)
    it really *is*
    > worth it.
    >
    >
    >
    > "josh" <josqb@cinci.rr.com> wrote in message
    > news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > > I've been struggling to fully understand the poor color representation
    of my
    > > scanned and later printed color photos. After looking at the printer end
    of
    > > the process I'm now looking at the scanner. I recently scanned genuine
    > > Pantone color samples
    > > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > > analyze the samples on its cymk sliders. The result for the cyan sample
    was
    > > c-79% m- 21% y - 8% k- 0%.
    > > The other colors had similar "contamination". Am I right in thinking
    that my
    > > inexpensive 8 year old Epson needs to be replaced?
    > >
    > >
    >
    >
    >
    >
  7. Archived from groups: alt.comp.periphs.scanner (More info?)

    Greetings RSD99.

    You have said RGB readings, but you are listing 4 numbers.
    RGBG.
    What is the fourth number? I think Red Green Blue Green. If so why two
    Greens?

    --
    CSM1
    http://www.carlmcmillan.com
    --
    "RSD99" <rsdwla.NOSPAM@gte.net> wrote in message
    news:oPKyc.14683$H65.5683@nwrddc02.gnilink.net...
    > You are apparently just beginning to find out why soooo many people talk
    soooo da*# much
    > about "Color Management."
    >
    > First, a couple of random thoughts about your posting, and predicament.
    Some of the things
    > you need to consider are
    >
    > (1) HOW are you getting your CYMK measurement(s). All scanners ever made
    work natively
    > (internally) in RGB. If you are loading the image into PhotoShop (or any
    other image
    > editing program) and measuring the patches with the eye-dropper, WHAT are
    the settings in
    > PhotoShop for the RGB --> CYMK conversion? Note that there essentially are
    an INFINITE
    > VARIETY of these conversion factors available for this translation in
    PhotoShop,
    > PhotoPaint, or other image editing program.
    >
    > (2) OK ... you've just gone to the time and expense of purchasing some
    Pantone color
    > chips. You get a 'Very Good' for effort, but you have NOT gotten the right
    thing to
    > analyze your situation. Why? Several reasons.
    >
    > First:
    > There is always very significant "color contamination" in any and all
    printing inks, and
    > Pantone color chips are made with printing inks. What you describe is
    fairly normal for a
    > Cyan (printing) ink.
    >
    > Second:
    > The Pantone Color Chips are not designed to be used for "calibration"
    applications. You
    > need something that is. That would probably (best case) be a calibrated
    IT8 target. They
    > are *expensive,* but available from several vendors.
    >
    > A usable solution might be getting something like a Kodak Q13 Grayscale /
    Color Patch
    > set. They are *not* calibration / analytical grade, but they work pretty
    well for getting
    > you into the ball-park. Cost would be about $20 ... and they are available
    form some of
    > the larger photography suppliers ... for example, I *think* I've seen them
    at B&H. Another
    > option would be to get a Gretag-Macbeth Color Checker, which is often used
    in the
    > photography field, and is pretty consistent. Cost would be something like
    $70 ... and they
    > are available form some of the larger photography suppliers. The
    difficulty with both the
    > Q13 and The Color Checker is getting accurate numbers for what they
    *should* read.
    >
    > Note that recently there has been a rather long (and very interesting)
    discussion of the
    > use of exactly these color "standards" in the Color Theory list hosted by
    Dan Margulis.
    > Incidentally ... any of his books are well worth reading.
    >
    > http://groups.yahoo.com/group/colortheory/
    >
    > As a point of reference, I just scanned the color patches on one of my
    Kodak Q13 Color
    > Patch targets. Here are the measurements in RGB ... I'm not including
    measurements in CYMK
    > because my conversion setup is probably quite different than yours.
    >
    > Numbers are on the PhotoShop 0-255 scale.
    >
    > Cyan Patch
    > R = 41
    > G = 159
    > B = 200
    > G = 128
    >
    > Magenta Patch
    > R = 211
    > G = 35
    > B = 107
    > G = 96
    >
    > Yellow Patch
    > R = 238
    > G = 215
    > B = 68
    > G = 206
    >
    > Additionally ... you asked:
    > "... Am I right in thinking that my inexpensive 8 year old Epson needs to
    be replaced?
    > ..."
    >
    > I just replaced my old scanner with an Epson 4870 PRO ... and yes, (IMHO)
    it really *is*
    > worth it.
    >
    >
    >
    > "josh" <josqb@cinci.rr.com> wrote in message
    > news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > > I've been struggling to fully understand the poor color representation
    of my
    > > scanned and later printed color photos. After looking at the printer end
    of
    > > the process I'm now looking at the scanner. I recently scanned genuine
    > > Pantone color samples
    > > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > > analyze the samples on its cymk sliders. The result for the cyan sample
    was
    > > c-79% m- 21% y - 8% k- 0%.
    > > The other colors had similar "contamination". Am I right in thinking
    that my
    > > inexpensive 8 year old Epson needs to be replaced?
    > >
    > >
    >
    >
    >
    >
  8. Archived from groups: alt.comp.periphs.scanner (More info?)

    Unfortunately ... there's a LOT more to it than just twisting a knob.

    Suggestion:
    Do a web search ... using your favorite local search engine ... on the exact phrase

    color management
  9. Archived from groups: alt.comp.periphs.scanner (More info?)

    Sorry for the confusion ... it's Gray.

    The way I make the measurement(s) in PhotoShop, the Gray value just sorta 'pops out,' so I
    record it.
  10. Archived from groups: alt.comp.periphs.scanner (More info?)

    Yes, I believe so.

    --
    DaveW


    "josh" <josqb@cinci.rr.com> wrote in message
    news:E8hyc.78261$DG4.61908@fe2.columbus.rr.com...
    > I've been struggling to fully understand the poor color representation of
    my
    > scanned and later printed color photos. After looking at the printer end
    of
    > the process I'm now looking at the scanner. I recently scanned genuine
    > Pantone color samples
    > of pure cyan, magenta and yellow and then used Photoshop's eyedropper to
    > analyze the samples on its cymk sliders. The result for the cyan sample
    was
    > c-79% m- 21% y - 8% k- 0%.
    > The other colors had similar "contamination". Am I right in thinking that
    my
    > inexpensive 8 year old Epson needs to be replaced?
    >
    >
Ask a new question

Read More

Scanners Peripherals