DIY Cinema Digitizer
Keeping your videos safe is easy, right? All you need is enough storage space and those Gigabytes of childhood memories will stay right where you left them. But what if those memories were shot the old-fashioned way on 8 mm?
By design, Normal 8, Super 8 and similar videos won’t last. The cellulose acetate decomposition, a self-catalyzing degradation of the film backing that’s also called the Vinegar Syndrome, is known to ruin those precious childhood memories. It even resulted in companies and products designed to digitize them. For the avid hobbyist Wolfgang Kurz, however, buying a product was simply not an option. Instead, he designed his own cinema digitizer.
Starting out his career as land-surveyor, Wolfgang Kurz followed his passion for technology and became an IT engineer when he was 29. Now pensioned, he still follows his passion at 76 by designing applications from his home in Stuttgart.
Keeping it affordable
Ten years ago, Wolfgang designed a Java-based program called CineToVid. This was followed by CineToVidPro, based on Microsoft C# with .NET. With CineToVidPro, users can digitize their 8 mm, 9.5 mm (Pathé) and 16 mm cine films using Windows 7 or a more recent version of Windows in combination with a good flatbed scanner. Although not the ideal solution, using a flatbed scanner was the obvious choice to keep the costs low as digital microscopes were fairly expensive, making it perhaps too expensive for most people.
This all changed dramatically over the last years according to Wolfgang. “Now you can get a digital microscope for less than 40 Euro with a resolution of 720P HD (960 x 720 pixels or better with a 1.3 Megapixel chip – 4:3 aspect ratio). And that is more than sufficient for Super 8 digitization.” The result is the CineFrameCatcher.
Step by step, frame by frame
Before, the process required the scanning of filmstrips, allowing for strips of 4 to 36 frames (depending on the transparency unit width of the scanner) to be scanned and digitized. The frames would then be extracted from the strips and put into a sequence to generate the digital video. However, the manufacturing tolerances of consumer flatbed printers make this extremely difficult. These tiny differences might not be a problem when working with still images, but can lead to irksome transitions between the frames – requiring severe adjustment calculations in the software.
This is no longer necessary thanks to the new Cinema Digitizer – capturing one frame at the time in the exact same position with a digital microscope. To ensure each frame being placed exactly the same, the DIY solution uses a transport wheel with teeth that grip in the little holes of the strip, using a rotation angle identical to the distance from one hole to the next. By ensuring that one tooth of the transport wheel always transports one single frame, the angle will always be the same. “And here normal stepper motors have a problem because the accuracy is only about 5% – and that is too much,” according to Wolfgang.
The easy to use TMCM-1110 StepRocker solves the problem. Splitting up a full step into 256 microsteps, it allows for the accuracy demanded in the CineFrameCatcher. Depending on the transport wheel used (10, 20 or 25 teeth), you can set the number of steps accordingly so that one tooth translates into one frame. Furthermore, the module also provides power to the stepper motor, keeping the BOM of this do it yourself-project short and simple. The software developed by Wolfgang, together with a (free to use) video editor will take care of stabilizing the individual frames and putting them in a sequence, so that you can relive your childhood memories once more.
Do you also have an interesting project using our solutions that you want to share? Leave a comment and Corné will get in touch with you.
November 29, 2017 / Trinamic / 1