Archived posting to the Leica Users Group, 2006/07/13

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Subject: [Leica] RE: Re: The Last Words on B&W Scanning (Don Dory)
From: hoppyman at bigpond.net.au (G Hopkinson)
Date: Thu Jul 13 17:25:23 2006

Don, I'm a keen student on BW scanning and printing currently. A number of
LUG people have been kindly offering suggestions and other help or opinions.
I know that both you and Tina recommend this scanning of BW as RGB. Others
are happy to scan at greyscale.

Would you explain why you feel the RGB method is superior? Certainly the
file is much larger, and you can manipulate those channels for more control.
But it seems to me that the RGB channel information is false, in that there
is no colour information to be had. So the scanner is interpreting the grey
image to invent the colour information. 

I'm leaving aside file manipulation after the scan for printing or other
reproduction. Also, I'm not referring to producing BW images from colour
negs or transparencies.
You are describing producing (very desaturated) colour images from a black
and white original.
Regarding scanning resolution, my take is that there is no benefit in using
less than the maximum real (not interpolated)resolution. I'm assuming here
that the system used won't take much longer to produce say a 4000dpi scan vs
2000dpi.  Certainly the time difference is more significant with flatbeds
and/or larger than 35mm, though.
Still, you will have extracted the most possible (scan) information from the
film. Then from that best possible file you can down-sample as you wish,
dependant on output desired. 

I understand your advice regarding setting the black white points and the
curve dialogue. Another approach is to have the scan software adjust as
little as possible and do this with the more powerful Photoshop along with
the crop and sharpening etc after you have your "raw" scan. Different
philosophy

Cheers

Hoppy
Very willing to learn

  

-----Original Message-----
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Message: 6
Date: Thu, 13 Jul 2006 16:44:21 -0400
From: "Don Dory" <don.dory@gmail.com>
Subject: Re: [Leica] The Last Words on B&W Scanning
To: "Leica Users Group" <lug@leica-users.org>
Message-ID:
        <9b678e0607131344m17e8691eg7791ca6c2f7acfd4@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Bob,
Definitely scan in RGB mode as you will get a larger file with more
information.  Always scan at the largest bit depth that your scanner will
allow.  Now comes the hard part, at what resolution to scan at.  All I can
suggest is to try the same negative at different resolutions and see what
comes out.  I have seen grain aliasing on one set of negatives that a fellow
lugger helped me with by scanning on his Leaf.

Last, turn off any sharpening in the scan phase.  Also do enough adjustments
after the prescan that you get all the information from the negative.
Typically that involves adjusting the white and black points as well as
using a curve dialogue to bring the tonality close to what you want.

Don
don.dory@gmail.com


On 7/13/06, bob palmieri <rpalmier@depaul.edu> wrote:
>
> Folks -
>
> Okay; I'm trying to get over my general disappointment with the way my
> B&W film scans looks (Tri-X or Neopan 1600 in Xtol).  I now need to
> scan several things within the next coupla hours.
>
> I see a lot of you folks posting some damn good-looking B&W images from
> these film/developer combos. Is the collective wisdom that I should
> scan the negs as color negs??  Howzabout scanning as positives and
> flipping them in Photoshop??  Does scanning at 3200 or so often lead to
> less grain aliasing than 4800? (I have a not-so-great Epson 2870 and
> Silverfast.)
>
> Since I use the Digest mode, if anyone feels so kind as to E me
> directly I'd sure appreciate it.  I gotta get these thing out...
>
> Bob Palmieri
>
> _______________________________________________
> Leica Users Group.
> See http://leica-users.org/mailman/listinfo/lug for more information
>


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Replies: Reply from don.dory at gmail.com (Don Dory) ([Leica] RE: Re: The Last Words on B&W Scanning (Don Dory))