A farmhouse, a beach, or a city roof can be the right subject under the wrong sky: a flat overcast when you wanted a clear late afternoon, or a gray band that makes the fields look duller than they were. Replacing the sky, and only the sky, keeps the building, the trees, and the horizon you already have.
Two CanvaPro tools cover that edit in slightly different ways. The object replacer is built for a masked object plus a short description of what should take its place. You upload a JPG, PNG, or WEBP up to 5 MB, cover the sky, and describe the new weather. The AI generative fill tool uses a brush and eraser, a minimum brush size of 10, and a description of the area you painted, on the same file types and 5 MB limit. For a large, simple sky, either can work. For a sky that weaves through branches or a complicated roofline, a careful brush mask is often easier to control.
Match the light you already have
The ground remembers the original weather. An overcast farm has soft, even light on the walls and almost no hard shadows. A hard orange sunset pasted on top of that lighting will look like two different afternoons taped together. When you describe the new sky, stay close to the light that is already on the stone and the grass: a brighter overcast, a gentle late-day glow, a clearer blue that still feels like the same hour.
If you truly want a sunset, be prepared to accept that the fields may not match, or to describe a milder evening rather than a postcard fire in the clouds. Reflections in windows and puddles should follow the new sky. If they still show a gray ceiling, include those small highlights in a second, tighter mask.
A full scene change behind a person or a building is a different job, covered in how to change a photo background with AI.
A practical sequence
- Upload a still under 5 MB where the horizon is clear enough to mask. A farmhouse against an open sky is easier than a dense forest canopy.
- Mask only the sky at first — not the cypress, not the roof. Add the thin triangles of sky between branches if they matter at the size you will post.
- Describe a sky that fits the existing light, generate once, and look at the horizon. A hard seam along the hills is more distracting than a slightly softer cloud.
- Fix leftovers with a smaller mask on a missed patch, rather than painting the whole sky a second time and risking a new edge.
A full scene change behind a person or a building, not just the sky, is a job for the AI background changer.
Trees, wires, and the horizon
Thin objects against the sky are the usual trouble: a cypress edge, a power line, a chimney. If the new sky bleeds onto the tree, pull the mask back and run a smaller fill, or leave a little of the original halo if it is less obvious than a chewed silhouette. Do not force a perfect cut on a tiny, messy file; start from a sharper original when you can.
Keep the horizon honest. Inventing a mountain range that was not there, or raising the sun to a place the shadows contradict, turns a weather change into a new landscape. A replaced sky should still be the same place at a more useful hour, not a postcard from somewhere else.
Masking just the sky, then describing the weather, is a close cousin of the steps to replace an object in a photo.
A short checklist
- Use a photo you have the right to edit, in JPG, PNG, or WEBP under 5 MB.
- Mask the sky carefully, especially around trees and roofs, and describe weather that matches the light on the ground.
- Inspect the horizon and any reflections, then repair small misses instead of regenerating the whole sky.
- Keep the original file. A sky change is a creative edit, not a record of the hour you stood there.
Seasons, color grade, and a light touch
A winter field under a summer blue sky can look as wrong as a sunset over even overcast light. If the grass and the bare trees say late autumn, describe a sky that could belong to that season. You can still brighten a heavy gray; you do not need to import July.
After the sky is in, resist a heavy color grade that then fights the new clouds. If the stone of the farmhouse picked up an orange caste you did not want, a smaller second fill is rarely the fix — the house was never in the mask. Either accept a milder sky, or make a modest, even adjustment to the whole still in your own editor, and keep a version without that grade. The goal is a place at a more useful hour, not a postcard that no longer matches the walls.
A modest, well-matched sky is usually more believable than a dramatic one that fights the fields. When you are ready, start with a still that already has a clean horizon, describe weather the light can support, and check the roofline before you save the new version.
Describe weather the ground can support, then mask the sky and run the object replacement tool once; fix small misses with a tighter mask rather than a new sky over the whole frame.