{
  "comparison_UTC": "2026-10-20",
  "reference": "Oct 19 11:50 globe median",
  "definition": "Exactly 1:1 source pixel to comparison pixel, no geometric resizing, centered by measured Saturn position; differences in original ROI/canvas removed; equalized upper-globe luminance through per-capture global RGB neutral multiplier, same multiplier applied to all three presets per capture. Originals unchanged.",
  "warning": "Same displayed pixel size does not guarantee physically identical angular scale for different optical configurations, other years or planet distances. Here both 2026 sessions measured ring span 470 vs475 px (<1.1% difference).",
  "target_median_linear": 0.4581742286682129,
  "gain_per_capture": {
    "Oct 19 11:50 PM": 1.0,
    "Oct 18 11:01 PM": 0.9362921098548403
  },
  "matched_median_8bit": [
    0.45811372995376587,
    0.458090215921402
  ],
  "samples": [
    {
      "capture": "Oct 19 11:50 PM",
      "preset": "Original punchy",
      "image": "Saturn_20261019_2350EDT_P10_FullTopaz_PunchyOct07Rings.tif",
      "original_size": [
        624,
        264
      ],
      "globe_center": [
        312,
        114
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 1.0
    },
    {
      "capture": "Oct 19 11:50 PM",
      "preset": "Warm Golden Globe",
      "image": "Saturn_20261019_2350EDT_P10_FullTopaz_PunchyOct07Rings_WarmGoldenGlobe_PunchyWhiteRings.tif",
      "original_size": [
        624,
        264
      ],
      "globe_center": [
        312,
        114
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 1.0
    },
    {
      "capture": "Oct 19 11:50 PM",
      "preset": "Richer Gold v2",
      "image": "Saturn_20261019_2350EDT_P10_FullTopaz_PunchyOct07Rings_WarmGoldenGlobe_RicherGoldV2_EvenGlobeWhiteRings.tif",
      "original_size": [
        624,
        264
      ],
      "globe_center": [
        312,
        114
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 1.0
    },
    {
      "capture": "Oct 18 11:01 PM",
      "preset": "Original punchy",
      "image": "Saturn_20261018_2301EDT_P10_AS4_TopazFull_PunchyOct07_Rings.tif",
      "original_size": [
        480,
        300
      ],
      "globe_center": [
        239,
        132
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 0.9362921098548403
    },
    {
      "capture": "Oct 18 11:01 PM",
      "preset": "Warm Golden Globe",
      "image": "Saturn_20261018_2301EDT_P10_AS4_TopazFull_PunchyOct07_Rings_WarmGoldenGlobe_PunchyWhiteRings.tif",
      "original_size": [
        480,
        300
      ],
      "globe_center": [
        239,
        132
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 0.9362921098548403
    },
    {
      "capture": "Oct 18 11:01 PM",
      "preset": "Richer Gold v2",
      "image": "Saturn_20261018_2301EDT_P10_AS4_TopazFull_PunchyOct07_Rings_WarmGoldenGlobe_RicherGoldV2_EvenGlobeWhiteRings.tif",
      "original_size": [
        480,
        300
      ],
      "globe_center": [
        239,
        132
      ],
      "output_scale": "1 original pixel = 1 comparison pixel",
      "gain": 0.9362921098548403
    }
  ],
  "pair_filename": "Saturn_Oct19_2350_vs_Oct18_2301_RicherGoldV2_1to1_MatchedBrightness.png",
  "three_preset_filename": "Saturn_Oct19_2350_vs_Oct18_2301_ThreePresets_1to1_MatchedBrightness.png"
}