Guide
A camera-scanning setup can be fast and detailed when the lens, alignment and film flatness are right. Here is a practical route from the rig to the raw files.
Use a camera that shoots raw, a macro lens suited to the required reproduction ratio, a film holder, a light pad, and a copy stand or tripod. Extension tubes and bellows can work; check corner sharpness and field flatness at the actual capture ratio.
Use an even, diffused light source. CRI 95 or higher and 5000–5500K are common starting points, not a guarantee of colour accuracy. Check for flicker or banding before the session and adjust shutter speed if needed.
The sensor plane has to be parallel to the film, or only part of the frame is in focus. The reliable way: put a small mirror on the light pad and adjust the camera until the reflection of the lens sits dead centre in live view. A spirit level only tells you anything if the tripod column is truly vertical.
Curled film moves the edges out of focus. Start with a film holder. If glass is needed, test the actual film for reflections and Newton rings.
Start at base ISO and test the lens for its sharpest aperture; f/5.6–f/8 is a common starting range. Focus manually with magnified live view, use a remote release or timer, shoot raw, and keep the bright end of the histogram from clipping.
Open the raw files in negaflow and the film base is found for you: it groups connected regions in the brightness distribution and drops sprocket holes, the holder and bare backlight. If the result is off, sample unexposed film with the eyedropper or type the RGB in.
