Top/Learn/Movie Stack/Jカット
どんな時に使う?

旅・vlog

ショートドラマ

ドキュメンタリー
使うと、どう変わる?
音が先に来て、画が答え合わせになる。
使わないと
普通のカット
音と画が同じ瞬間に変わる
使うと
Jカット
電車の音が、画より先に来る
AI でどう作る?
STEP 1
次のカットは頭を長めに
伸ばす音は、使わない頭から取る
AI への指示J-cut source 1: a static medium shot on the overpass; the next shot's sound will arrive before its picture. J-cut source 2: a static high wide shot looking down from the overpass at the railway tracks, so the sound source becomes visible. No people in the frame.
J-cut source 1: a static medium shot on the overpass; the next shot's sound will arrive before its picture. Character: the man from the character reference sheet: same face, small scar at the end of the left eyebrow, short slightly messy black hair, open plain dark-navy cotton overshirt jacket with one left chest pocket over a plain white crew-neck T-shirt, charcoal grey chinos, black plain sneakers. Location: a pedestrian overpass with green-painted steel railings above a two-lane road, railway tracks running alongside the road below. 0.0s-1.5s: he stands at the railing, forearms resting on it, looking down the road. 1.5s-3.0s: he lifts his head and turns toward the right, as if hearing something coming. 3.0s-5.0s: he keeps looking right, waiting. Shot on a cinema camera with a 50mm lens, one soft overcast sky as the only light source, real skin texture with pores, visible fabric fibers, painted steel railing with chipped paint, cotton jacket. Natural, neutral color, no heavy grading. No text, no logos. Ambient sound: light traffic below, wind. J-cut source 2: a static high wide shot looking down from the overpass at the railway tracks, so the sound source becomes visible. No people in the frame. Location: a pedestrian overpass with green-painted steel railings above a two-lane road, railway tracks running alongside the road below. 0.0s-1.5s: the tracks are empty; overhead wires hum. 1.5s-4.0s: a plain silver commuter train with no markings passes from right to left below. 4.0s-5.0s: the last car leaves frame; the wires sway. Shot on a cinema camera with a 35mm lens, one soft overcast sky as the only light source, steel rails, gravel ballast, overhead wire texture. Natural, neutral color, no heavy grading. No text, no logos. Ambient sound: a commuter train passing, rails clacking rhythmically.
STEP 2
音の主役を画に写す
音源になる物を具体的に書く

音の主役
仕上げのひと手間は?
Jカットそのものは編集で作る。画は普通に切り、音の切れ目だけ前へずらす。
POINT 1
音だけを前へ伸ばす
リンクを外し、次の音声の頭を左へ

音が先に 
画が後で POINT 2
重なりをフェードでなじませる
かすかに入れ、切れ目で本来の音量に
よくある失敗は?
✕ よくある失敗
先行が長すぎる
○ こうする
2 秒までにとどめる








