Module 3 · Colour: HSL & Selective Colour
Goal: use the HSL panel to control individual colour channels independently — shift hues, boost only certain saturations, and brighten specific tones without touching others. The hue extreme-swing drill is the key practice exercise.
📱 Use NotebookLM on your phone
AI summary · chat Q&A · audio podcast · personal notebook
Scan
How to use NotebookLM here
Click "Copy YouTube links" and open NotebookLM. For extra practice: add a photo of Barcelona streets with varied colours as a reference point for your questions.
Questions to ask NotebookLM:
- "How do I make a sky more dramatic using only the HSL panel?"
- "What's the hue extreme-swing drill and why does it train your eye?"
- "When should I use selective colour vs HSL vs a mask?"
- Scan QR code with your phone camera
- Click "Copy YouTube links"
- Open NotebookLM → create notebook → add sources
- Wait ~30 sec and start asking
Recommended videos
Key concepts
- HSL — three dimensions of colour: Hue (what colour — shift orange toward yellow or red), Saturation (how vivid — per channel), Luminance (how bright that colour is — darken blue sky without affecting other colours).
- Colour channels: Red, Orange, Yellow, Green, Aqua, Blue, Purple, Magenta. Each slider only affects pixels whose colour falls in that range. Skin tones live in Orange-Red. Sky is Blue-Aqua. Foliage is Yellow-Green.
- Hue extreme-swing drill: for each channel, drag the Hue slider to +100, observe which pixels move, then drag to −100. This teaches you exactly which parts of your image belong to each channel — essential before making real adjustments. Key drill to practise.
- Practical sky enhancement: Blue Hue slightly negative (shifts toward cyan = deeper sky). Blue Saturation +15–25. Blue Luminance −10 to −20 (darker = more dramatic). Check that it doesn't spill onto buildings (if walls are similar blue, use masking instead).
- Selective colour vs HSL: HSL affects all pixels of that colour globally. Selective colour (range masking, colour range mask) lets you target a specific region by colour AND location — more precise, but more work. Use HSL first; add a mask if bleed is a problem.
- Luminance for skin: Orange Luminance +10–15 brightens skin without boosting saturation. Cleaner than lifting Exposure globally.
Self-check exercises
1. You want to make the sea in a Barcelona harbour photo look more vivid without affecting the golden stone buildings. Walk through your HSL approach.
Step-by-step:
- Do the hue extreme-swing drill on Aqua and Blue channels — identify which channel the sea water falls under (likely Aqua or Blue depending on the colour of the Mediterranean light)
- Boost Aqua/Blue Saturation +20–30
- Optionally shift Aqua Hue slightly negative (toward cyan) for a richer sea blue
- Lower Aqua/Blue Luminance −10 to add depth
- Check the buildings: if the stone starts looking affected, the yellow-orange channels are not involved — but if shadows in the stone have a blue tint, you may need to pull back
- If the sea and sky merge into one over-boosted blob, keep the sky natural with Blue Luminance and reserve Aqua for the water
2. A street portrait has a slightly green cast on the subject's skin. How do you fix it with HSL without affecting the green foliage in the background?
Skin tones sit primarily in the Orange and Yellow channels. A green cast on skin usually means the skin has too much Yellow channel Saturation or the Hue is off.
Fix:
Fix:
- Yellow Hue: shift slightly toward orange (positive direction) — this moves the skin's yellow component away from green
- Yellow Saturation: reduce slightly if the cast is strong
- Orange Hue: shift slightly toward red if needed
3. After doing the hue extreme-swing drill on a photo, you notice the Orange channel moves both the skin AND an orange wall in the background. What do you do?
This is exactly what the drill is for — revealing unintended bleed. Since both the skin and the wall are in the Orange channel, you can't separate them with HSL alone.
Options:
Options:
- Accept it: if both skin and wall are moving in the same direction and both look better, no problem
- Use a subject mask: apply an HSL adjustment specifically to the subject using a person/subject mask — Photomator supports AI subject masking. Adjust Orange on the masked version only
- Use a range mask: in the local adjustment, use a colour range mask to sample just the skin tone area — restricts the edit by colour within the masked region
- For quick edits: do the global Orange adjustment for skin, then locally correct the wall with a separate brush mask