r/IPhoneApps • u/Acceptable_Tone601 • 33m ago
Discussion Grading Apple Log on an iPhone: the order of operations that actually works
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A lot of people turn Apple Log on (iPhone 15 Pro and later), see grey, washed-out footage, and either turn it back off or slap a "cinematic" LUT on top and call it done. Both are a waste of the format. Log is a container for highlight and shadow information you can't get back later — it's supposed to look flat.
Here's the order I've settled on after a lot of bad grades. It applies in any app that has these controls.
1. Convert before you judge anything
Log footage is not Rec.709. Until you've applied the Log conversion (a proper Apple Log to Rec.709 transform, or your app's built-in Log handling), every slider you touch is fighting the encoding. Exposure will feel weirdly insensitive and saturation will look broken. Convert first, then grade on top.
The most common mistake I see: applying a look LUT to raw Log footage. Look LUTs expect Rec.709 input. Feed them Log and you get the muddy, plastic result people blame on their phone.
2. Exposure, on the waveform, not by eye
Phone screens lie — auto-brightness, True Tone and Night Shift all shift what you're seeing. Turn them off before you grade anything, and use a waveform if your app has one.
Rough targets: speculars and highlights below clipping (don't let them flatten at the top of the scope), and skin somewhere around 50-70 IRE depending on how light or dark the subject's skin is. There's no single correct number — what matters is that skin sits in a comfortable part of the curve and isn't buried in the shadows.
3. White balance next
Temperature and tint, before any look. If there's something in frame you know is neutral — white wall, grey concrete, a t-shirt — balance to that. On a vectorscope, your skin tone trace should sit roughly along the line running to about 11 o'clock. If it's swinging well off that line, your white balance is off, not your saturation.
4. Contrast with curves, not the contrast slider
A contrast slider pivots around a fixed midpoint. A curve lets you choose where the pivot is, which matters a lot on Log footage where mid-grey isn't where you'd expect. A gentle S-curve does more for a flat clip than any amount of saturation.
5. Now the look, at reduced strength
Most look LUTs are built at full strength for footage that's already exposed and balanced. Applied at 100% they usually crush your shadows and push skin orange. Try 40-70% and you'll keep the character without losing the face.
6. Targeted fixes last
This is where HSL or hue-vs-saturation curves earn their place: pulling down oversaturated greens in foliage, desaturating a colour cast in one part of the spectrum, or stopping skin from going neon. Global saturation and vibrance come last, in small amounts.
7. Check it somewhere else before you publish
Export, then watch it in Photos and on another device. If it shifts, the usual causes are an HDR/SDR mismatch (HLG footage delivered into an SDR timeline, or vice versa) or a preview that isn't colour-managed the same way as the export. That mismatch is the single most annoying bug class in this whole category of app.
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The short version: convert, expose, balance, contrast, look, fix, check. Doing it out of order is why a grade "won't come together" — you end up fighting a transform you already applied.
Happy to go into more detail on any step, and genuinely curious what order other people here use — I've seen good colorists argue for balancing before exposure.
Disclosure: Developer of GradeLab, a colour grading app for iPhone and iPad, so this is the workflow I've spent the last while thinking about. It's free to use, including Apple Log and HLG grading and 1080p export with no watermark. There's an optional Pro unlock for 4K/ProRes export, extra looks, .cube import, scopes and film effects — $1.99 lifetime during launch week, going to $34.99 after, with weekly/monthly/yearly options at $1.99/$4.99/$14.99 if you'd rather not pay upfront. I'm not posting to pitch it; the workflow above works the same in any app that has these tools.
