De-screeing applies only to images published in newspapers or magazines. They are made using a method called halftone images, which consists of various sizes of dots. The text of the newspaper does not use the halftone method and articles can be scanned normally. Halftones on the other hand need to be dealt with differently. Some scanners can try to "de-screen" or remove the dots and smooth the image or images. The trouble with this is that halftones use different dots per inch and unless you select the correct dpi to remove the halftone effect you get a picture that is a mess. Alignment also has a lot to do with de-screeing. If the lines of dots do not match up exactly with the scanner then all bets are off. In my experience scanning halftones it is almost impossible to get a good image as a result. I have at times scanned at a very high dpi and then reduced the dpi in Photoshop or similar program and got a useable image, although it is rare. To understand halftone use a high power magnifying glass and look at a picture in a newspaper and you will see the dots of varying sizes that make up the image. These dots are what creates the strange patterns you see when you try to scan a halftone image.
Photocopies, such as made on a Xerox machine do not create halftones, just black and white images. Generally speaking they are also poor candidates for using in publications but sometimes that is all you have and you have to go with it. The reason is there are no mid tones (grays) in the image. The copy machine looks at the original and either interprets a place on the image as black or white, there is no in between. It is still a challenge to get a useable image for publication. Photographs (and I am speaking of black and white in this instance) are continuous tone images with a range of gray scale running from pure white to pure black with all the various stages of gray scale in between. From pure black to pure white is usually considered a perfect picture in B&W terms. Look at a Ansel Adams or Edward Weston print and you will see the range is all the way from pure black to pure white. A scanner scanning B&W will interpret the image in 256 shades of gray, from pure black to pure white which simulates a continuous tone image to the eye. If the image was recently published in a newspaper you may be able to contact the paper and get a computer scanned image of the original photo before it was halftoned. If you are speaking of an old newspaper the chances are slim that you will ever be able to get a true copy of the image. As with all things you have use what you have to work with but halftone images never reproduce as good as you would like. Good luck, Ken ----- Original Message ----- From: "Emily Moore" <eall...@aol.com> To: <LegacyUserGroup@LegacyUsers.com> Sent: Thursday, July 26, 2012 4:11 AM Subject: [LegacyUG] Best practices for scanning photocopies I have a number of photocopies, mostly obituaries from newspapers, that I would like to scan and add to my Legacy Family Tree file as multimedia images. I know the importance of descreening when scanning original images of newspapers or magazines. Does that apply to photocopies as well? What about scanning photocopies of handwritten originals such as deeds or Bible records? And what is the best way to scan photocopies of typewritten or printed material? Legacy User Group guidelines: http://www.LegacyFamilyTree.com/Etiquette.asp Archived messages after Nov. 21 2009: http://www.mail-archive.com/legacyusergroup@legacyusers.com/ Archived messages from old mail server - before Nov. 21 2009: http://www.mail-archive.com/legacyusergroup@legacyfamilytree.com/ Online technical support: http://www.LegacyFamilyTree.com/Help.asp Follow Legacy on Facebook (http://www.facebook.com/LegacyFamilyTree) and on our blog (http://news.LegacyFamilyTree.com). To unsubscribe: http://www.LegacyFamilyTree.com/LegacyLists.asp Legacy User Group guidelines: http://www.LegacyFamilyTree.com/Etiquette.asp Archived messages after Nov. 21 2009: http://www.mail-archive.com/legacyusergroup@legacyusers.com/ Archived messages from old mail server - before Nov. 21 2009: http://www.mail-archive.com/legacyusergroup@legacyfamilytree.com/ Online technical support: http://www.LegacyFamilyTree.com/Help.asp Follow Legacy on Facebook (http://www.facebook.com/LegacyFamilyTree) and on our blog (http://news.LegacyFamilyTree.com). To unsubscribe: http://www.LegacyFamilyTree.com/LegacyLists.asp
