one take, every aspect ratio

stop reshooting the same video for tiktok, then reels, then youtube. shoot once in open prompter, crop to every platform later.

it's the same script, the same outfit, the same lighting. the only thing that changes between platforms is the shape of the frame. so don't reshoot the performance. reshape the export.

the reshoot trap#

here's the loop most creators are stuck in.

you write a script. you record a vertical for tiktok. then you remember reels wants vertical too, fine, that one's reusable. then youtube wants a horizontal. so you reset the camera, find your light again, and read the whole thing a second time. then someone wants a square for the feed. read it a third time.

three takes. one idea. that's three chances to flub a line and three afternoons that turn into one.

the fix isn't talking faster. it's capturing a source you can crop in every direction.

five shapes, one app#

open prompter records five aspect ratios. 9:16 vertical, 1:1 square, 4:3 classic, 16:9 horizontal, and open gate.

the first four lock the shape at capture. pick 9:16 and you get a tall file, ready to post, no editing step. that's the move when you already know the clip only lives on one platform.

open gate is the move when it doesn't.

open gate records the full front sensor instead of cropping it down to a delivery shape. on iphone 17 the front sensor is square, so open gate writes a true 3840x3840 square to the file. that square has slack on every side. there's room to crop a tall vertical, a wide horizontal, a classic 4:3, or leave it square, all from the one take.

if you want the full story on why a square is the most crop-friendly source you can shoot from, that's its own post: why open gate matters on iphone 17.

frame for the crop, not the take#

shooting wide and cropping later only works if you frame for it. one rule covers it.

keep your head and your action inside a center-safe zone.

picture the tightest crop you'll need, the 9:16 vertical, sitting in the middle of the square. now picture the 1:1 and the 16:9 stacked over it. the spot they all overlap is the center column. put your face there. keep your gestures there. anything that drifts to the far left or right edge of the square will survive the wide crop but get chopped out of the vertical.

a few things that pay off later:

• leave headroom. a little space above your head means a vertical crop won't clip your hair and a horizontal crop won't feel cramped.
• stay centered. if you drift left while you talk, the vertical crop drifts with you or loses you. center is safe for every shape.
• keep props and hand gestures in the middle third. the edges are the first thing any crop throws away.

frame like the camera is already cropped to vertical, even when it's recording the whole square. then every other shape is slack you didn't have to fight for.

the editing step#

this is the part that turns one take into a week of clips.

one performance. every size. and because you captured the whole square, you can slide the crop window around inside it. drifted left in the take? slide the 9:16 frame left to recenter your head. that flexibility doesn't exist once the crop already happened in-camera.

the resolution holds up too. a 9:16 crop out of a 3840 square is 2160 wide and the full 3840 tall. a 16:9 crop is the full 3840 wide and 2160 tall. you're not blowing up a tiny region. you're framing a window inside a big square and exporting what's in it.

the iphone 17 caveat, honestly#

the true square readout is an iphone 17 thing.

if you're on an older phone, the multi-platform workflow still works, you've got more headroom in one direction than the other. plan your crops around the taller axis and you're fine.

the rest of the setup#

while you're reading, the camera lives inside the teleprompter as a small tile near the lens, so your eye-line stays close to the camera. it never gets jammed behind your text. you can drag the tile anywhere, or turn it off entirely.

the script itself is a plain markdown file from a folder you pick once. write it on your mac, save it, the phone catches up. record your open-gate take, and if you turn on "save next to the script," the .mov lands right back in that same folder next to the .md.

and if you want hands-free, a Bluetooth remote or the hardware buttons can start and stop the recording while the phone stays mounted and untouched.

try it on your next batch#

pick one script. set the aspect ratio to open gate. record it once, framed for the center.

then go cut a vertical, a square, and a horizontal out of that single take. that's your afternoon back.

open prompter is free and MIT-licensed. all five aspect ratios, the camera, the recorder, all of it.