Photo Editing Guide

Photo Editing Guidelines

When editing photos, always call analyze_image first to see the histogram, zone balance, and color data before choosing adjustment values. This prevents over-editing.

Then apply edits with edit_image following this professional Lightroom-style workflow in order:

1. Exposure & Light (get the tones right first — check the analysis for current exposure):

   • exposure — correct overall brightness. Direction: gamma > 1 BRIGHTENS, < 1 DARKENS. Midtone-weighted — prefer it over brightness (a linear multiply that clips highlights faster). Scale the move to the miss (read mean luminance from analyze_image; a decent daylight photo lands around mean 100-130):
     • mildly off (mean within ~30 of target): gamma 1.05-1.2 (or 0.85-0.95 to darken)
     • clearly dark (mean 60-90): gamma 1.3-1.6
     • severely underexposed (mean < 60): gamma 1.8-2.2 is legitimate — the 0.85-1.2 range will barely move it (measured: gamma 1.2 + shadows +30 moved a mean-32 photo only to 42)
   • highlights — recover blown highlights (amount -15 to -50 for recovery, conservative)
   • shadows — open up dark areas (amount +10 to +35 for recovery, conservative)
   • Response curve note: highlights/shadows effects are progressive — below ~20 the change is nearly invisible and it steepens toward 50. Move in steps of 10-15 and read the Tone check line after each pass.
   • whites — white point (level is RELATIVE: positive brightens highlights, negative compresses them; 0 = no change)
   • blacks — black point (level is RELATIVE: negative deepens toward pure black (-20 to -40 to restore depth after dehaze or on faded scans), positive lifts (10-20 for the faded/matte look), 0 = no change — it does NOT mean "pure black")
   • contrast — overall contrast (factor 1.03-1.15, subtle is better)

2. Presence (add punch and clarity):

   • clarity — midtone local contrast (amount 15-35 on 0-100 scale, don't exceed 40)
   • dehaze — cut through haze in outdoor shots (strength 0.15-0.35, don't exceed 0.5). Dehaze lowers the mean — on a genuinely hazy photo that drop IS the fix (the veil was false brightness), so judge by the median: compensate with a small exposure lift only if the median fell well below ~100 on a daylight shot. If shadows stay at 0% after dehazing (blacks still lifted), finish with blacks -20 to -40 to restore depth.

3. Color (warmth and tone):

   • saturation — overall color intensity (factor 1.03-1.12 for boost, 0.85-0.95 for muted)
   • hsl_adjust — fine-tune individual colors (values -100 to +100, but use -30 to +30 typically):
     • Boost orange/yellow saturation (+10 to +20) for warm skin tones
     • Shift greens toward teal (hue -10 to -15) for modern landscape look
     • Desaturate blues slightly (saturation -10 to -20) for cleaner skies
   • split_tone — cinematic color grading (keep strength LOW: 0.08-0.15):
     • Shadows: blue tint (hue 210-230, saturation 30-50, strength 0.08-0.15)
     • Highlights: warm tint (hue 25-40, saturation 30-50, strength 0.05-0.12)
     • Classic "orange and teal": shadows blue (hue 220), highlights orange (hue 30)

4. Detail (always denoise before sharpening):

   • denoise — reduce noise first (strength 2-3 for most photos, 4-5 for high-ISO)
   • sharpness — add sharpness after denoising (factor 1.15-1.4)

5. Finishing touches:

   • Slight blacks lift (level 10-20) for the modern faded/film look
   • Consider color_temperature for overall warmth (>5500 warm, <5500 cool)

Critical rules for natural results:

• Always use analyze_image first — never guess values blindly
• Clipping in the SOURCE is unrecoverable. If analyze_image shows more than a few % clipped whites (≥250) or blacks (≤5), that detail is gone — no highlights/shadows amount brings it back (measured: highlights -40 on a 30%-blown sky left 28% clipped). Contain instead: darken/brighten the mids so the rest of the frame reads well, and say so rather than stacking recovery passes.
• Verify numerically after: every tonal edit result ends with a "Tone check" line (mean/median luminance, zone %, clipping — before → after). Read it. If the mean moved further than planned, or clipped whites/blacks grew, fix it with ONE small follow-up edit — do not stack another full editing pass, and do not judge brightness from the inline preview alone.
• The effects compound: 6 subtle adjustments > 1 heavy adjustment
• If shadows + highlights are both pushed hard, the image will look flat/HDR — be conservative
• Never exceed: highlights ±50, shadows ±35, clarity 40, dehaze 0.5, split_tone strength 0.15
• The "professional" look comes from restraint, not from maxing out sliders

Tips:

• Less is more — subtle adjustments compound. A 5% change in 6 things beats a 30% change in one.
• Always denoise BEFORE sharpening — sharpening amplifies noise.
• The faded blacks look (lifted black point) is a hallmark of professional editing.
• Split toning with complementary colors (blue shadows + orange highlights) creates depth.