How to Invert Colour Film Negatives in Photoshop

Using Replicable Equalization Technique

7 min read by Dmitri.
Published on . Updated on .

This guide will demonstrate and explain a simple, reliable method for making high-quality positives from scanned colour film negatives.

There are three steps. The first two list the precise instructions for obtaining an optimal amount of visual data to create an equalized positive. The final step is colour correction.

Prep: Tools and media.

In the example below, I am using Adobe Photoshop 2021. However, this method is transferrable to other image processing software, like Lightroom, Gimp, ImageMagick, etc.

This method will work with RAW files, TIFFs, JPEGs or any file types, sizes, and qualities. For best results, I recommend using high-bit-depth images.

Download my sample film scan off PrimeFilm XA to follow along as I edit it below:

➜ Free Download: Sample uncompressed 48-bit 35mm Film Scan (TIFF)

1. Invert the image (Negate) — 5sec.

Let’s begin with the simplest and most straightforward step in this process. Load up your negative scan into Photoshop and create a new Invert adjustment layer (fig. 1 — A).

Figure 1: Add an Invert adjustment layer (A). It will create a layer on top of your scan that you can edit non-destructively (B).

Note 1: Creating a layer on top of your scanned negative, as opposed to editing the image layer itself, ensures that there’s minimal loss of quality in your final image. This technique is called non-destructive editing.

Note 2: You will need to use a different technique to invert colours if you use Lightroom or Camera RAW.

At this point, you will likely notice a strong blue cast on top of your image. This effect will depend to various degrees on your exposure, film type, and scanning device type. Essentially, you’re seeing the film’s orange mask, but it is now the opposite of orange — blue. We will work on fixing that next.

2. Remove noise (Equalize) — 25sec.

Time to create a usable image out of your scan: an equalized positive.

Create a new Curves adjustment layer (fig. 2 — A), and select the Blue colour channel (fig 2. — B). Have a look at its histogram (fig. 2 — C).