For film and fiche scanning, what is your REAL speed to scan, process, QA and then output – not just how fast a scanner can theoretically capture a roll of film? You want to verify what is the speed to complete the 4 basic steps in your process? a) Image Scanning, b) Detecting images and generating meta-data, c) Audit/QC, d) Output. Furthermore, you not only want to verify that you have the best Production Throughput in the market but also the best Image Quality produced with RAW, uncompressed data captured with true optical resolution (without interpolation / scaling or “double speed” i.e. half resolution).
The most important metric for a scanner is the total throughput for fully processed rolls into satisfactory images per the user’s specification and how much operator time this requires. This information cannot be easily found from the manufacturers specifications as every application is different, and at times the information available can be misleading. Furthermore, when all stated vendor specifications are reviewed, are you really comparing apples to apples?
Beware speeds quoted on a manufacturer product datasheet. Many times, these are quotes based on very best case scenarios (the perfect film with simplest scanning parameters), or these quotes can be numbers that are not realistic for any scenario. For example, a scanner rated at 325-350 pages/minute might actually only produce about 250 pages/minute using standard film (16mm, 200 dpi, 24x reduction ratio, 8.5” wide image with a 2.5” gap between frames). The speed quoted on the product specifications may have been declared using a 0 gap between frames, a different reduction ratio or low resolution – all of which may not be realistic for film scanning in a real world scenario. There are some vendors who think when you specify a 200 dpi image, that they can supply an image scanned at 100 dpi, by 300 dpi and then scale the image to 200 by 200 dpi. The image quality is abominable, but since they get to scan at 100 dpi in the scanning direction, they get twice the speed and you get half the image quality. Some vendors call this “double speed”, when they really mean ½ image quality.
Additionally, when quoting speeds for processing entire rolls of film, many times it is not specified for the reader the length of the roll and the type of resolution being employed to arrive at those numbers.
The actual speed of any film scanner is going to always depend on the type of film being scanned and the user’s image requirements. More importantly, speed should really be measured in terms of the overall scan process, not just how fast the scanner can capture a roll of film. Scan time, detection editing, image conversion and QC are all relevant factors. For a true estimate of potential Scanning speed for your microfilm projects, reach out to your vendors for a demonstration.
Joe Merkel
Western Regional Sales Manager