Archived posting to the Leica Users Group, 2006/07/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hoppy, I scan in RGB mode as I don't want the scanner to control any part of the scan process. In RGB mode you are using all the sensors in the scanner to record exactly whatever they see. In grayscale I don't know if the scanner is norming some pixels as there is no color information; this is too much for me. Secondly, the RGB file in PS offers more bits to manipulate so less clipping off of potentially valuable information, again, I am in control of what goes into the image. Part of this is back in the old days of 8 bit files. My theory on adjustments is that I want to manipulate the image bits as little as possible. So, if I adjust the scan then there is less to do in PS so less loss of data as severe adjustments are done. An exception to this would be an image that I think shows promise but I am not sure what I want to do with it. In that case I will output a pretty flat image that still holds data from almost white almost black. Indeed, these files will capture all the information on the negative that the scanner can capture. Don don.dory@gmail.com On 7/13/06, G Hopkinson <hoppyman@bigpond.net.au> wrote: > > 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 > > > > > ------------------------------ > > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >