Archived posting to the Leica Users Group, 2006/07/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]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----- ------------------------------ 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 > ------------------------------