Choosing a plate that will move

A photograph that looks extraordinary as a still can be useless as a plate, and the discovery is always made late, after the frame has been approved and the schedule has closed.

Separation is everything

A parallax build takes a flat image apart and moves the pieces at different rates. That only works if the pieces come apart.

Frames with atmospheric perspective - fog between ridges, haze on a distant valley, mist over water - separate almost by themselves, because depth is already encoded as contrast and colour. A luminance-based extraction gets you most of the way to clean planes in minutes.

A flat, evenly lit scene with no atmosphere has to be rotoscoped, and rotoscoping a treeline is a genuinely miserable way to spend two days for a result that will still have an edge on it.

Search the atmosphere tags first. It is the highest-leverage decision in the whole process.

Depth cues for a push

A push-in needs something to push toward. A frame with a strong centre - a lit clearing, a distant peak, a converging valley - gives the move a destination and the audience a reason to accept it.

A frame with even interest across the width fights a push and works far better with a lateral move.

Decide the move before you choose the plate, not after.

Resolution headroom

The arithmetic people forget. A push consumes resolution continuously, and the frame that matters is the tightest one.

Push 25 per cent into a shot and the last frame uses 80 per cent of your width. To finish at 3840 usable pixels you need 4800 before the push, after the aspect crop. A parallax build needs more again, because backgrounds are enlarged relative to foregrounds and holes behind moved elements have to be filled.

Work backwards from the tightest frame, then add ten per cent for the reframe somebody will ask for.

The hole problem

When you move a foreground element, you expose what was behind it. Generative fill handles sky and water well, distant terrain adequately, and anything with recognisable structure badly.

Choose plates where the moved elements have sky or haze behind them rather than detail. This is a compositional property you can see in the still, and it predicts a day of work.

Grain last

Match grain at the delivery resolution, after the grade. A clean plate dropped into grainy footage reads as a still no matter how well it is graded, and matched grain fixes it in one operation.