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The film must be scanned transversally on the flat bed scanner, as shown in the figure. You can use the Dia module delivered with the scanner, or, if you have a normal scanner, you can try the method described at
http://home.sci.fi/~animato/scanning/scanning2.html.
The scanning resolution is a compromise between the quality you expect, the size of files you are ready to manage and the money you want to spend. I would suggest a resolution between 1200 and 3600 dpi. For your reference, the intrinsic film resolution is around 3000 dpi, while professional 35mm scanners use 4000 dpi. You have to keep the scanned strip size below 40-50 MB, otherwise you may have problems with the computer memory, and the time needed to load and save the files. After acquisition, the processing can be done through smaller JPEG files, but this is slower than processing directly the bitmaps.
Here is an example of regular8 mm strip (2400dpi, 676x7527 pixels, 24bit color, around 15MB in RAM, compressed jpg file is 695kB, it will take time to load...) (it's my father and me in 1960).
You can see a good example of what could be a 3600dpi Super8 frame at: http://www.modopticals.com/moose1.html
Because the number of acquisitions is high, the scanner must be used with stored parameters; you have to tune the preview, the scanning area, the exposition, the saturation etc. once and for all. Here is an example of TWAIN interface.
The main problem during film acquisition is keeping trace of which frames have been acquired and which have not. Here you are free to invent any technique. I have been using very simply adhesive paper (e.g. from CD or address labels), cut in tiny pieces and placed on the last scanned frame. Also, it is important to keep the film parallel to the scanning line. Again several methods are possible, I have modified the 35mm film interface, as shown in the following figures (I have added 2 small wings on the interface, in order to keep the film against the border).
The wing on the right (bottom in the scanned image) is opaque, in order to be seen on the scanned strip. The frame just above is the last frame (bottom frame), and must be marked, after scanning.
It will be then visible on the left (top), at the next scan, and the first frame will be easy to identify.
If you use a normal scanning software you can do the job, but you loose a lot of time to rotate the strip (which is acquired horizontally and should be displayed vertically), to give a logical file name and to save the file to a given directory. With 8mm2avi this work is simplified (file names are generated automatically, the rotation is by default).
Acquiring the film strips