Prepare consistent camera captures

Before you start

Prepare the camera, lens, film holder, and transmission light, and keep the original files. The consistency described here applies to digitization settings, not the exposures originally used to photograph scenes on film.

Steps

1. Group files by roll

   Use one roll per project where possible. Before combining rolls, check that stock, development—including push or pull—storage, and capture settings closely match. The same stock name is not enough. Separate files with different film, processing, lights, or input handling. If unsure, create separate projects.

2. Stabilize the camera, film, and light

   Keep the camera parallel to flat film and inspect center/corner sharpness at magnification. Fix magnification, distance, and focus, and mask unnecessary transmitted light to reduce flare. Check uniform areas for bands, brightness drift, or local casts before capture; address these at the source rather than expecting demasking to repair them.

3. Fix exposure and turn off Auto ISO

   Prefer camera RAW. In M mode, fix ISO, aperture, and shutter speed and disable Auto ISO. Keep light brightness, color mode, and channel ratios constant too. Camera ISO is a digitization setting, not a copy of the film’s rated speed. Choose a suitable low native ISO and an aperture balancing sharpness and depth of field, then test the shutter speed rather than applying universal numerical settings.

4. Test bright transmission and dense regions

   Test representative frames and clean low-density film base. Avoid capture clipping in any RGB channel within usable film, not just in overall brightness. Also inspect usable signal and detail in dense regions. The camera histogram generally reflects a processed preview, so it alone cannot prove that RAW is unclipped. Direct light through perforations is not an image highlight for judging film exposure.

5. Use the same capture settings for the roll

   Once the test settings are suitable, keep them unchanged across the roll rather than letting metering alter exposure for each composition. Differences in subjects and original film exposures are normal. Fixed digitization exposure preserves those differences instead of adding a new scale factor to each frame. Record and handle separately any frame that needs another exposure.

6. Use matching settings for chart and flat-field references

   CCM charts must match the camera, actual illumination, and input interpretation; do not mix an RGB-lit negative capture with a White-lit chart. Match flat-field references to the lens, aperture, magnification, and illumination too. A RAW white-balance tag differs from white balance baked into RGB files. Avoid mixing per-frame automatic white balance, levels, or strong curves into an otherwise shared input. Recheck calibration after setup changes.