A Technical Look at the dokko Workflow

The dokko scanner was developed to capture more usable detail, maintain stronger geometric accuracy, and preserve more tonal information than the legacy scanners still used in many film workflows. The comparisons below are meant to show those differences in practical terms.

Comparison dokko / Imacon

Below is a comparison of a 35mm detail scanned with dokko and with an Imacon, one of the most widely used high-end film scanners still in service. The red area marks the enlarged detail.

comparison 01 dokko overview
Some footnotes:
  • the 3150ppi sample might look sharper than the 4000ppi sample on small screens because it's more pixelated.
  • the 6300ppi sample has about the same detail as the 8000ppi sample, this is due to the lens in the Imacon scanner being unable to resolve more than around 5500ppi.

How dokko Compares

Many scan services still rely on older scanner designs. The table below summarises the main workflow and image-quality differences that matter in practice.

dokko Imacon / Hasselblad Drum Scanners Flatbed
True optical resolution Up to 40,000 ppi ~5,500 ppi ~5,000-6,000 ppi ~2,400-4,000 ppi
Optics Format-specific lenses Single lens, all formats Fixed optics Fixed optics
Edge-to-edge sharpness Consistent Often soft at edges Good Variable
Digital sharpening None (raw scans unsharpened) Applied, cannot be fully disabled Varies Varies
Film handling No liquids, no mounting, manual Elastic holder, automated Wet-mounted with oil/tape Glass carrier
Geometric accuracy Area sensor, no distortion Line scan, prone to distortion Drum rotation, minor issues Good
Full-frame capture Including edges/perforation Cropped by film mask Cropped by mounting Depends on carrier

To illustrate the geometric distortion issue with Imacon scanners: below is a detail of the same film scanned twice in an Imacon 848 with identical settings, showing how the line-by-line scanning mechanism introduces inaccuracies.

distortions Imacon / Hasselblad

Notes on Other Scanner Types

Drum scanners were groundbreaking systems, but the surviving models still in use are older designs with real-world limits in optical resolution and a workflow that usually depends on wet mounting and more invasive handling.

Flatbed scanners can still be useful, especially for some large-format work, but their real optical resolution is much lower and their results are less consistent when the job demands maximum detail.

Frontier / Noritsu minilab scanners are optimized for speed and convenience. They can be perfectly serviceable for quick lab output, but they are not designed for archival masters or the largest, most demanding print workflows.