Digitization of Color Negatives with Capture One (C1)
NOTE: Most of the following workflow can be saved as a custom C1 style and then auto-applied on tethered capturing. Frame individual adjustments I consider absolutely necessary are marked with an asterisk.
NOTE 2: By now I‘ve distilled the workflow (and a bit more) into a free helper tool for Capture One Pro on MacOS nicknamed „Analogue Toolbox“. A supporting group has been created at https://www.facebook.com/groups/141662290513120/ . Feel free to join if interested.
- Set Auto-Levels channel mode to „Red, Green and Blue channels“
- Set Auto-Levels clipping to 0.1% for shadows and highlights. Negative material defects or fluff can throw off the Auto-Levels feature. If in doubt try with settings between 0.2 and 0.1 or temporarily crop leaving the defect area outside of the frame and reset the crop after conversion.
- Capture an image from the light source alone without any negative in between. Ensure exposure is on point (+/- 0)
- Create a LCC from it with Color Cast and Enable Uniform Light enabled. Do not enable Dust Removal.
- If your lens has Auto Focus - you might want to use it
- If the negatives arch a bit towards the center try to focus a bit off-center to maximise depth of field.
- When tethering ensure that Orientation is fixed in Next Capture Settings to prevent arbitrary rotation with a downward pointing camera.
- Capture the negative. Try to always expose around +/- 0.0 in camera. *
- Set Curve to "Linear Response"
- Apply Lens Correction if available with your lens but apply without vignette correction (handled implicitly by LCC)
- Apply LCC using the previous created LCC image
- Adjust Noise Reduction: Luminance: 0, Details: 50, Color: 40, Single Pixel: 0
- Adjust Sharpening: Amount: 160, Radius: 1, Threshold: 0, Halo: 0
- Optionally auto-whitebalance using unexposed frame
- Invert via RGB Levels: 0 —> 255, 255 —> 0
- Adjust RGB overall gamma (via midpoint marker). Setting it to -0.25 is often enough.
- Crop without leaving any border *
(You can still remove the crop as last step if desired.)
- Apply Auto-Levels *
- Adjust channel individual Gamma * of red and blue using midpoint adjustment of the respective channels in levels tool. Use only red and blue midtone points! Usually red needs to go into the - area while blue needs to go into the + area. These are very fine slider adjustments. Use a RGB Color Readout picker on middle grey areas to assist. Red -14 & Blue +14 is often a good starting point.
- Apply a Luma-Curve (S-shaped).
* = needs to be handled on a per-image basis.
- Export to TIFF, 16-bit, sRGB w/ output sharpening and all metadata
- Apply custom 3D LUT via Affinity Photo, Photoshop or similar LUT capable software (Download Link)
- Convert to SRGB afterwards… and save as JPG
DT Culture Heritage: Digitization Workflows: Transmissive