How to Choose a Panorama Projection When the Default Stretches the Scene

A projection maps the assembled scene onto a flat image. Different mappings distribute distortion differently, so a successful stitch can still have proportions you dislike. Adobe’s panorama engineer describes alignment and projection as separate stages: the photographs are arranged around a virtual sphere, then mapped onto a plane for display. Adobe: From the ACR Team—Merge to Panorama

Start by describing the visible problem precisely. Is a whole object smoothly widened near the edge? Does a continuous straight feature become a curve? Or does the feature break where two photographs meet? Use the first two observations to guide projection comparisons. Treat a visible break as a reason to inspect the stitch before deciding which overall rendering looks best.

Also distinguish straightness from pleasing proportions. Rectilinear projection preserves straight scene lines, but that alone does not mean an extremely wide composition will look natural. The Hugin manual describes it as useful for prints covering a relatively limited angle, giving less than about 120 degrees as an example. That is a practical guideline rather than a universal aesthetic cutoff. Hugin manual: Rectilinear Projection

Before changing settings, name three things you want to preserve: one central subject, one feature near an edge, and one important line. For a mountain panorama, these might be the main summit, a rounded foreground rock, and the horizon. For a photographed interior, they might be a central doorway, a side window, and a ceiling edge.

Use this table to choose your first comparison. These are starting recommendations derived from the projection properties, rather than rules that determine the final image.

Your main priority	Start with	Inspect before accepting it
Straight lines throughout a moderately wide composition	Rectilinear / Perspective	Widened objects at the sides and stretched corners
A broad horizontal sweep with limited height	Cylindrical	Curved lines above or below the horizon
Extensive horizontal and vertical coverage	Spherical; equirectangular for a full-sphere output	Whether the flat rendering suits the intended photograph
A very wide composition with strong central perspective	General Panini, when available	Bowed transverse lines and changes caused by squeeze controls

The distinction between a spherical scene and its flat representation matters. Hugin documents equirectangular output as covering the full 360-degree surroundings, including directly above and below the camera. That coverage makes it useful for representing a complete sphere; it does not automatically make it the most pleasing flat print. Hugin manual: Hugin Stitcher tab

Keep rectilinear on your shortlist when straight edges carry the composition: shelving, window frames, paving joints, or long rooflines. It maps straight lines in the scene to straight lines in the image. Lightroom uses the name Perspective for its flat-surface option. Hugin manual: Rectilinear Projection; Adobe panorama documentation

If the center looks convincing but objects at both sides look excessively broad, compare a narrower rectilinear rendering with the full-width version. In a stitcher with output field-of-view controls, reduce the included angle. Alternatively, compare a central crop. Hugin’s documentation confirms that rectilinear output must stay below 180 degrees in both directions; that mathematical limit is considerably broader than the range you may find visually pleasing. Hugin manual: Hugin Stitcher tab

Ask a composition question before rejecting the crop: do the outermost objects contribute enough to justify their stretched appearance? If removing a small amount of scene produces a stronger photograph, keep the narrower version. If the full sweep is essential, move to another projection and judge which curved lines you can accept.

Cylindrical is a useful next test for a panorama that is much wider than it is tall. It preserves vertical lines and can represent a complete horizontal turn. Its trade-off is curvature in other straight lines, apart from the horizon in a correctly oriented view. A long horizontal feature above or below the horizon can therefore bow even while upright features remain straight. Hugin manual: Cylindrical Projection

Inspect the foreground as carefully as the skyline. A panorama may look convincing across distant peaks while a nearby straight ledge becomes conspicuously curved. Whether that matters depends on what the photograph asks the viewer to notice.

Cylindrical also has a vertical limitation: it increasingly stretches the regions approaching directly above and below the camera. If changing from rectilinear improves the sides but leaves an excessively elongated top or bottom, compare spherical output or include less vertical coverage. The cylindrical manual documents this increasing stretch toward the poles. Hugin manual: Cylindrical Projection

Try spherical when the panorama contains substantial height as well as width, especially with multiple rows of photographs. Adobe recommends it for very wide and multirow panoramas. Judge the result as a complete composition, then inspect the particular straight features that matter to you. Adobe panorama documentation

General Panini offers another option for wide scenes with strong perspective toward the center. It preserves verticals and radial lines passing through the image center while reducing the peripheral stretching associated with very wide rectilinear views. Its documentation identifies views with a central vanishing point as particularly suitable. Hugin manual: The General Panini Projection

Panini introduces its own compromise: transverse horizontal lines can bow. Adjustable squeeze controls reduce that curvature, but can increase curvature in radial lines. In Hugin’s documented implementation, compression is labeled “Cmpr,” with separate upper and lower squeeze controls labeled “Tops” and “Bots.” These parameters describe that implementation; other software may present different controls. Hugin manual: The General Panini Projection

For a practical test, first adjust compression while watching your chosen edge object. Then adjust squeeze while watching the important horizontal line. Finally, revisit the diagonals. Stop when another adjustment improves one feature only by making a more important feature worse.

Use a controlled comparison so you can see what each setting contributes. The following sequence is an editorial workflow derived from the documented trade-offs:

1. Save the starting project or retain the source photographs. Keep an easy route back to the original comparison.
2. Set Boundary Warp to zero, where available. Temporarily disable automatic cropping so the full boundaries remain visible.
3. Choose your three reference features. Use the central subject, edge object, and important line identified earlier.
4. Compare two suitable projections first. For example, compare Perspective with cylindrical for a wide, shallow scene.
5. Keep the intended subject and coverage comparable. Avoid choosing a preview simply because it shows a larger-looking subject.
6. Choose the geometry, then refine the crop. Add boundary adjustments gradually afterward.
7. Inspect the final render. Check the whole composition at its intended viewing size and examine joins at higher magnification.

Boundary Warp deserves a separate comparison because it stretches the panorama’s uneven boundaries toward a rectangle. Adobe’s engineer explicitly notes that this can introduce unwanted distortion. A projection that initially looks good can therefore change after boundary adjustments. Adobe: From the ACR Team—Merge to Panorama

Consider an illustrative panorama containing a wide mountain ridge, a rounded rock near the right edge, and a straight foreground ledge. Suppose Perspective keeps the ledge straight but makes the rock look elongated. Cylindrical gives the rock a more pleasing appearance but bows the ledge. These are hypothetical observations showing how to decide, rather than reported test results.

If the ridge is the subject and the ledge occupies a small strip at the bottom, try cylindrical with a tighter foreground crop. If the ledge is the main visual line leading into the scene, compare a narrower Perspective version. If both the full width and strong central perspective are essential, test General Panini if your stitcher provides it.

Choose the version that preserves your most important features within a useful crop. Finish by checking those same features after every final warp and export. A deliberate projection choice comes from knowing which shapes the photograph needs to preserve, then accepting the least distracting compromise in the rest of the scene.

• Merge photos to create HDRs, panoramas, and HDR panoramas — Adobe Lightroom
• From the ACR Team: Merge to Panorama — Adobe
• Rectilinear Projection — Hugin / PanoTools documentation
• Cylindrical Projection — Hugin / PanoTools documentation
• The General Panini Projection — Hugin / PanoTools documentation
• Hugin Stitcher tab — Hugin / PanoTools documentation