There has lately been some discussion about photos, picture files and scanning resolution here in this list Before I scan an old photo I evaluate which scanning resolution I need. In this connection I consider: - What is the resolution of my printer (and my screen)? - What is the resolution (details) of the very photo? The picture resolution of a printer is given in lpi(lines pr. inch). This figure is much smaller than the printerresolution stated in dpi(dots pr. inch). The lpi resolution of a 600 dpi printer is about 100 lpi, this will give about 64 greylevels. The lpi resolution of a 1200 dpi printer is usually in the same order (100 lpi), the number of greylevels are then just higher (say 256). In order to print a 100 lpi picture you will need a picture file with a resolution which is somewhat higher then 100 dpi to accomodate for interpolation errors during printing. A factor of 1.5 is usually recommended, in a few cases you may benefit just a little bit from a somewhat higher factor, say about 2. This means that a normal 100 lpi print will need a picture resolution of 150 dpi, at most 200 dpi. This resolution will also do for a PC screen. A screen of to-day has a resolution of about 100 dpi. Future high-resulution screens are not likely to exceed 200 dpi. When we look at the photo to be scanned we find that the details, the resolution, of a normal photo is no larger than corresponding to about 200 dpi. This may be surprising, but if you want to explore more details in your picture, you will have to look at the original negative film. The scanning of a 35 mm negative film requires a special scanner. This all leads me to scanning my photos in such a way that the final picture has a resolution af no more than 200 dpi. All my old photos are in black/white. A typical black/white photo of 4*6 inches will then get a raw filesize of about 960 kBytes. For use in Cumberland Family Tree it is a good idea to decrease the picture size to say 2*3 inches. This will reduce the raw filesize to around 240 kB. I get a further reduction of the filesize in CFTW by using JPG picture files. The JPG format is able to offer a noticeable reduction of the filesize, typically about 10 times, depending on the picture content. The mentioned 2*3 inch picture will then get a size within CFTW of some 25k. The JPG file format is a good choice for CFTW, but it is not well suited for archival purposes. The reason is that it involves some loss in picture quality, i.e. it will remove some of the lesser important picture details. This is usually not visible, but it may be unwanted for archival purposes. For archival purposes I choose between file formats like BMP, PCX, TIF and GIF. Neither of them are able to offer the same compression factors as JPG, sometimes they give no reduction in filesize at all, but they do not remove or reduce any picture details. I often use TIF with LZW compression. It will in most cases give the smallest file of those four formats mentioned. Erik