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  1. #1

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    Jan 2010
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    Scanning B&W film with v700 or v750

    So I'm hearing I should scan in RBG 16bit, then desaturated it in photoshop? Do i get better scans that way than using grayscale?

  2. #2

    Join Date
    Oct 2009
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    Scan in 16 bit RGB, then look at each channel's noise independantly, pick the lowest noise channel(normally green or blue) remove the other two, and make your desired adjustments from there.

    Don't just desaturate as it will give you the worst possible conversion.

  3. #3
    pschwart's Avatar
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    Quote Originally Posted by Rinthe View Post
    So I'm hearing I should scan in RBG 16bit, then desaturated it in photoshop? Do i get better scans that way than using grayscale?
    Color negs and transparencies are better scanned as RGB, then converted to b&w in Photoshop. This will give you a *lot* more control over image contrast and how tones are rendered. Just desaturating will usually not provide the best result. There are a lot of strategies for converting -- this is a whole other
    topic
    I scan b&w negatives as 16-bit grayscale. Photoshop tells me that all the channels of b&w negs scanned as 48-bit RGB have identical histograms, so I don't think there is anything to be gained (except file size) by scanning these as RGB.

  4. #4

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    For C41 process or real B&W films there's no need to scan in RGB, except for negatives developed in staining developers; you'll usually get better results by scanning those in RGB and choose which channel(s) hold the most useful data (=broader histogram + less noise/grain) later in PS...

  5. #5
    pellicle's Avatar
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    Apr 2008
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    Hi

    for black and white film, scan in 16 bit greyscale or if you wish 48 bit colour and then discard red and blue channel (it is the same thing if you try it).

    I also recommend you scan in postive mode as you can adjust the black and white points easier and not have a funny gamma associated with your scan by the epson driver. You can then apply any curves as you desire later.

    http://cjeastwd.blogspot.com/2010/02...-scanning.html
    Homepages: here
    Blog: here

  6. #6

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    Nov 2009
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    Quote Originally Posted by pschwart View Post
    I scan b&w negatives as 16-bit grayscale. Photoshop tells me that all the channels of b&w negs scanned as 48-bit RGB have identical histograms, so I don't think there is anything to be gained (except file size) by scanning these as RGB.
    I'd like to know how scanner noise behaves if you compare an RGB scan (converted to B&W afterwards) with a gray scale scan (straight from the scanner). With an RGB scan you basically take three samples of every pixel, which, if you average them, should reduce noise by a factor of 1.73. This may, of course, be a moot point, if the scanner internally does grey scale scans like this anyway.

  7. #7
    pellicle's Avatar
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    Apr 2008
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    Hi

    Quote Originally Posted by pschwart View Post
    I scan b&w negatives as 16-bit grayscale. Photoshop tells me that all the channels of b&w negs scanned as 48-bit RGB have identical histograms, so I don't think there is anything to be gained (except file size) by scanning these as RGB.
    perhaps even something to be lost ... check your channel registration. I find that its not always perfect between R G and B

    altering height can give better focus on a channel, but will often disturb the RGB alighment.

    this is from colour ...

    but I have seen similar in black and white.

    I now just use the grey scale.

    I was first tweaked to this some years ago ... it is not just me who finds this, I suggest this reading to you also:
    http://www.largeformatphotography.info/1800F-bw.html
    Homepages: here
    Blog: here

 

 
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