Effect 4: The Phone-Grab Portal — Key a Green-Screen Phone, Mask the Hand Frame by Frame, Zoom Through the Screen

Location optional but a rooftop, ocean or lake 'increases views.' Mount the smartphone to be grabbed on a tripod; walk up, grab it, and keep turning/walking a beat afterwards - that extra motion is the transition window. Second clip: film a phone top-down displaying the full-screen green image (in the shared zip) for about 15 seconds of editing room. Green must be distinct, saturated and properly exposed with no green elsewhere - the key is only as clean as the plate. Avoid all-black clothing: the AI cutout keyed on colour and got confused; contrasting colours mask easier.

Stack the green-phone clip above the grab clip and key the green so the grab footage shows through the screen. Split the grab clip (a) one frame before the hand is cut off by the screen edge and (b) a few frames after the body starts turning. Duplicate the middle piece to a layer above the green-phone layer and mask only the hand/arm, frame by frame, so it emerges in front of the phone. Keyframe the green-phone layer's scale from the grab moment to just before the arm would be clipped - CapCut 250, Premiere/Final Cut 'until the screen is gone', about 18-20 frames - so it zooms up and out, revealing the background. Keep the middle piece 1-1.5 s: longer means far more masking, shorter feels rushed.

Desktop (paid): stack, Video > Remove background > Chroma key, click the green, Intensity ~60 (higher bleeds into the other shot). Split the bottom clip before the hand is cut off and after the turn; Option-drag the middle piece up, Up arrow to snap; Remove bg > Auto Removal then Custom removal: mark keep/discard with the selector and Smart Eraser, frame by frame ('funky'), Apply; turn tracks back on. Video > Basic > Transform: Scale keyframe at the clip start, Scale 250 at the end (delete the stray Position key), split one frame past and delete the tail. Mobile (free): add grab then green, drag green behind, Effects > Overlay (stacking is inverted - overlays sit below), drag it over the grab track; Remove bg > Chroma Key, Intensity just until the green goes; Split at the two points (aim for a 1-1.5 s middle - check the timer); Duplicate the middle > Overlay > snap above; Remove BG > Custom removal > Brush (Quick Brush is Pro), size ~70 for areas / ~10 for detail, pinch-zoom, Eraser, tick; scrub and re-open Custom removal to fix the algorithm's misses (leg, thumb); re-snap any one-frame slip. Transition: select the green clip, keyframe at the grab, a few frames on, pinch straight up until the phone leaves frame.

Unlink and delete both audio tracks; label the green clip; move it above. Effects > 'Ultra Key' onto the green clip; eyedropper the green; clean with Matte Generation/Cleanup (Tolerance, Pedestal). Razor the grab clip before the hand clips the edge and after the turn; Option-drag the middle piece above the green layer; hide the green track. Effect Controls > Opacity > Pen, trace the hand (scroll-wheel click-drag to pan; Cmd+Z; Option-click flattens an accidental bow). Select Mask 1; every Right-arrow step plus adjustment keys a frame; Track Mask helps briefly then fails on the fast motion - finish by hand, drag points off-screen once the hand exits; box-select points from OUTSIDE the mask to move groups. Feather ~5, razor the tail. Green clip: right-click > Nest, add the Transform effect, untick the composition-shutter box, Shutter Angle 180; Scale keyframe at the grab, second keyframe zoomed until the screen is gone just before the hand would clip; Ease Out on the first, Ease In on the second.

Edit: both clips in, green above. Color: Add Alpha Output, connect the dots; Qualifier dropper on the green - it selects the wrong region, so Invert; In/Out ratio -100; raise Blur Radius until the green is gone without eating the phone screen. Edit: untick Link Clips, delete audio; Blade before the hand clips (one frame back) and at the turn; Option-drag the middle up. Color again: Add Alpha Output, Window > Pen around the hand; disable the top track to isolate; Tracker in Frame mode (clip tracking will not hold), Right arrow per frame adjusting points, double-click a point to make it a hard corner; points off-screen as the hand leaves. Edit: Zoom X/Y keyframe at the grab, step ~18 frames to just before the arm clips, one back. Black bars? File > Project Settings > 1080x1920, tick 'Use vertical resolution', Save. Then Transform/Zoom keyframe again and zoom until the phone is gone (the end key appears in red).

New Event/Project; both clips; green above. Effects > 'Green Screen Keyer' onto the green clip. Blade before the hand clips and after the turn; Option-drag the middle above the green; check sync at both ends. Canvas 75%, Effects > 'Draw Mask', points around the hand extending onto the sleeve; V to hide the phone track; open Control Points, keyframe on the row beside the effect title; Right arrow per frame, move individual points (never drag the whole mask - it shifts earlier keys), double-tap the canvas to add a point; when the hand exits, zoom the canvas to 25% or 12.5% to drag points off-frame - 'one of Final Cut's biggest limitations'; group-select unchanged points. Feather 3; V to reveal. Transform > Scale (All) keyframe at the grab; step ~20 frames (fewer if the cutout is small); raise Scale until the phone is out of frame.