Lasergraphics Director 10K Scanner
Color and B&W High Dynamic Range (HDR)
Many film archives hold enormous amounts of very high-density Color and B&W print, reversal and interpositive (I/P) film assets.
While the highest density on negative film is about 2.0, density of print film can often exceed 4.5. Thus, scanning print film requires up to 1,000 times more dynamic range than negative film. Unfortunately, most conventional film scanners, designed originally for Digital Intermediate (“DI“), were optimized to primarily scan low-dynamic-range negative film. As a result, these scanners are simply incapable of properly scanning high-density print film – resulting in shadow detail that is either very noisy or missing entirely.
In order to determine the capability of modern scanners to scan high-density motion picture film material (i.e. densities beyond 2.0), measurements were taken on images from color print film scanned by three leading high-quality film scanners:
• DFT Scanity HDR (single flash; NO Color HDR capability)
• ARRI ARRISCAN (double flash HDR mode)
• Lasergraphics Director 10K (triple flash HDR mode)
Continuous-motion film scanners are noisy in high-density areas
Continuous-motion film scanners (e.g., DFT Scanity HDR) typically use TDI “line sensors” to scan film. The film moves continuously past the TDI line sensor which has only 96 pixel lines. In contrast, the Director 10K uses a frame-by-frame scanning method whereby each frame is held motionless in the film gate for an entire frame time and exposed on an area sensor. As a result, each pixel on the film is illuminated for the entire frame time exposing all 1,556 lines of the Director 10K’s area sensor versus only 96 lines for the Scanity HDR TDI line sensor. The Director 10K can achieve this at scanning speeds up to nine frames-per-second (9 FPS)!
Consequently, the Scanity HDR TDI line scanner is “light starved” because each pixel is only exposed for 1/16 (i.e. 6%) of the frame time.
This starvation of light results in noisy images, as seen clearly in the comparison below. The image was generated by scanning the same Color Negative Film frame with the Director 10K area sensor and the Scanity TDI line sensor.
The width of the histogram indicates the level of noise in the highly exposed area of the Color Negative Film being scanned. In this comparison, the area sensor has significantly less noise than the line sensor in areas of higher density.
This noise problem becomes much worse for the TDI line sensor as the density of the film increases – and high-density is very common in Color and B&W print, fine grain I/P, and reversal films.
Lasergraphics Director 10K 3-Flash HDR Blows Away All Competitors!
Some portions of the original negative film are often missing when an older film must be scanned. This requires print or I/P film – with densities of 4.5 or higher – to be substituted for the missing portions, which creates significant issues for virtually all other high-end film scanners on the market.
Unfortunately, conventional film scanners (e.g. ARRISCAN, Scanity, and others) were originally designed and optimized primarily to scan negative film for DI. As a result, these scanners are incapable of properly scanning high-density Color print film – resulting in shadow detail that is either very noisy or missing entirely.
By comparison, the sprocketless and pinless Director 10K – uniquely engineered for archive scanning – uses proprietary Lasergraphics 3-Flash HDR technology to easily capture shadow details with minimal noise from ALL high-density Color and Black & White film stocks where all other competing scanners fail.
To illustrate, the same frame of highly dense (i.e., very dark) Color print film was scanned as a 16-bit TIFF image on the Director 10K, the ARRISCAN, and the Scanity. Each TIFF image was then digitally gained up by a factor of approximately 1000x so that the 3 images appeared similar.
As expected, all of the images exposed with a single flash exhibit similar high levels of noise. This noise is the result of the physical limitations of the image sensor technology.
Two of the three manufacturers (Lasergraphics and ARRI) have overcome this image sensor noise limitation by exposing Color (and B&W) images multiple times at different intensity (i.e. flash) levels.
NOTE: The DFT Scanity HDR cannot make multi-flash HDR exposures of Color Film because the film moves continuously across its TDI line sensor. In contrast, both the ARRISCAN and the Director 10K hold the frame completely still during the entire exposure cycle, enabling multiple HDR exposures for both Color and B&W film.
Below are the best results that can be achieved from the Scanity, ARRISCAN and Director 10K when scanning dark (high density) color print, reversal or I/P film:
Both the Director 10K and the ARRISCAN have significantly less sensor noise than the Scanity HDR – and the Director 10K 3-flash HDR is clearly less noisy than the ARRISCAN’s 2-flash HDR.
The Director 10K is the only scanner which has implemented 3-flash HDR technology in order to extract all of the high-density information from both Color and B&W film. It is practically noise-free in high-density images from all Color and B&W films.