Milky Way

How to Photograph the Milky Way Arch: Panorama Planning, Shooting and Stitching

By Still DarkPublished Sep 12, 2026Updated Sep 12, 202612 min read

A single frame shows the Milky Way core over a horizon. The arch is the whole band from one horizon to the other, with the core at one end and Cygnus at the other, and no lens covers it. The arch spans about 180° of horizon and rises to 80–90° at its peak. A 14 mm on full frame covers ~104° across its long side, and a rectilinear lens wider than that smears stars at the edges. So you shoot the arch as a Milky Way panorama, a set of overlapping frames swept along the band and stitched into one image. This guide covers when the arch is low enough to fit, how to shoot the sweep, and how to stitch it. For the basic per-frame settings, start with the Milky Way guide.

Why the arch needs a panorama

The band is a great circle on the sky, so the half above the horizon is always 180° wide. When it's low, it rises as an arch to 40–60°. When it's high, it crosses the zenith. A 14 mm covers 104° along its long side, a 20 mm 84°, a 24 mm 74°. A fisheye gets it all in, but the horizon comes out curved and the stars at the edges are smeared into arcs.

A panorama avoids the problem. Each frame covers a small part of the sky and stays sharp, and the software maps the set onto a cylinder or sphere and unwraps the result.

When to photograph the Milky Way arch: low and complete

The galactic centre is in Sagittarius at RA 17h 45m, Dec −29° (the position of Sagittarius A*). That declination limits how high it can climb. From 40° N the maximum altitude is 90° − 40° − 29° = 21°. From 50° N it's 11°, and from 30° N it's 31°. The core is always low from northern mid-latitudes. What changes with the hour is the band's angle to the horizon.

In the hours after the core rises, the band runs along the eastern horizon as a long, low arch, with the core at the south-east foot and Cygnus at the north-east. Through the night it pivots up until it stands nearly vertical through the zenith. You only get the complete arch soon after the core has risen, so the calendar looks like this:

• March to May, before dawn. The core rises after midnight and the arch is low and complete in the two or three hours before astronomical dawn. This is the main northern arch season. Capture the Atlas puts the single-row arch window at late March to late May.
• June to August, early evening. The arch is still fairly low when astronomical darkness begins, but it climbs fast. By late evening in July and August the band is vertical, and the short nights at high latitudes don't leave you much time.
• Southern hemisphere. The core passes overhead in the middle of the night from April to August, which is the hardest time for an arch. Low arches come before dawn early in the season (roughly February–April) and in the evening late in it (September–November).

Use these months as a rough guide. The hours shift with latitude and date, and the only reliable way to know the arch's shape at a given hour from your spot is to simulate it.

When the band is high. On a July night at 1 am the band goes straight overhead. There's no arch to frame, but you can shoot a vertical panorama. That's a column of portrait frames from the southern horizon up through the zenith, stitched with a spherical projection. It looks like a pillar, not a bridge, and it's still a good picture.

Planning the sweep: night, hour, lens, frame count

1. Pick the night from the Moon-free windows. Even a crescent low in the west washes out the fainter end of the band.
2. Pick the hour when the arch is low and complete, and note the azimuths of the two feet, typically south-east to north-east before dawn in spring.
3. Pick the focal length. 14 mm gets the arch in four frames. 20–24 mm gives more detail without too many frames. At 35 mm and longer you need more than one row.
4. Count the frames from the table, plus one spare at each end, and decide how you'll shoot the ground.

The frame counts below come from each lens's rectilinear field of view on full frame, in portrait orientation, with 40% overlap. Crop sensors need about 1.5× as many at the same focal length.

"Shoot in practice" adds a spare frame at each end. You need a second row whenever the frame's vertical field (84° at 20 mm, 74° at 24 mm, 54° at 35 mm) can't hold both the arch's top and the horizon, which is nearly always at 35 mm and longer.

Shooting the Milky Way panorama, frame by frame

1. Level the tripod. This decides whether the horizon comes out straight. Use the bubble level. A levelling base between the legs and the head makes it a ten-second job. If you level a ball head by eye you get a banana-shaped horizon, and no projection will straighten it later.
2. Portrait orientation. You get more sky above the horizon in each frame, so you need fewer rows.
3. Overlap 30–50%. The software matches stars in the overlap, and 50% is the usual recommendation at night, when frames have few features to work with. Use the head's panning scale so every step is the same.
4. Parallax and the nodal head. If you pan a camera about any point other than the lens's entrance pupil, near objects shift against far ones between frames, and the stitch tears at the foreground. Stars never show parallax. So a panoramic (nodal) head only matters when something is within a few yards of the lens, such as a rock, a fence or a tent.
5. Full manual, identical for every frame. Manual exposure, fixed white balance (~4000 K), manual focus set on a bright star and then left alone. Auto white balance or auto ISO give you frames that differ in colour and brightness, and the seams show.
6. Per-frame settings from the NPF rule. 20 mm f/1.8, 13 s, ISO 3200 is a good starting point. Check the shutter limit for your sensor in the 500 rule and NPF rule guide. Trailed stars stitch worse than sharp ones.
7. Shoot quickly, back to back. The sky moves 15° an hour. A 10-frame row at 20 s plus gaps takes about five minutes, during which the sky turns 1.25°. Stitchers can handle that, but any time you spend adjusting things between frames adds to it. Start at the end where the Moon is due.
8. Then the ground row. Tilt down so it overlaps the sky row by a third and repeat the sweep at the same settings. Or shoot one long low-ISO exposure of several minutes (or a frame at twilight from the same tripod position) to blend later. If you light-paint, do it once, with a single sweep of a torch, not once per frame.

Stitching: software and projection

Any of these will stitch a well-shot night panorama:

• Lightroom Classic / Camera Raw: Photo > Photo Merge > Panorama. Included with Lightroom, works from RAW, returns an editable DNG. Boundary Warp fills the ragged edges without cropping.
• PTGui: paid, for Windows, macOS and Linux. The standard tool for difficult stitches, with control-point editing and masking.
• Hugin: free and open source (GPL), for Windows, macOS and Linux. It can do a lot, but it takes longer to learn.
• Affinity Photo: File > New Panorama, with a Panorama persona for cleanup.
• Microsoft ICE: the old free favourite, retired in 2021 and no longer downloadable from Microsoft.

Projection. The projection is how the sphere of sky gets flattened onto a rectangle. Rectilinear (perspective) keeps straight lines straight but stretches the edges more and more as the view gets wider. It breaks down past ~120° and can't represent 180° at all. Cylindrical keeps verticals straight and handles a 180° arch cleanly, so it's the usual choice for a single-row arch over a horizon. Spherical (equirectangular) maps the whole sky including the zenith. Use it for multi-row, vertical and 360° panoramas.

When it goes wrong. Frames that won't align usually have too few stars to match (cloud, or a bright foreground light) or were shot too far apart in time. Try Spherical, mask the foreground, or drop the frame if the overlap allows. A curved horizon comes from a tilted tripod or a perspective projection. Switch to cylindrical and don't force the ground flat. Ghosting, such as a car's lights appearing twice, can be masked in the stitcher or cloned out afterwards.

Beyond the single row

Multi-row and 360°. Two or three rows at 24–35 mm cover arch and ground in one grid. Four or five rows of a 20 mm around the full horizon plus a zenith frame make a complete sphere. Reproject that as a stereographic "little planet" and the band wraps around the sky as a ring.

Trackers. A star tracker lets each frame run for minutes at low ISO and shows far more of the band, but the ground blurs, so the ground row has to be shot untracked and blended. It's only worth doing if you want a deep arch.

Mosaics are panoramas of a small region at long focal length, say the core at 85 mm in six frames, where every frame is a stacked, tracked exposure.

Phones. The built-in panorama mode won't work at night, because it needs a fast shutter and continuous motion. Take individual Night-mode frames on a tripod, overlapping as above, and stitch on a computer. See the iPhone astrophotography guide.

Common mistakes

• Forgetting the ground row, so the arch stands on a strip of black.
• Auto white balance, so every frame has a different tint and the seams show.
• Refocusing mid-panorama. If you touch the ring, the star sizes change between frames.
• Too little overlap, leaving too few stars for the stitcher to match.
• An unlevel tripod, giving a banana-shaped horizon that no projection can straighten.
• The Moon rising mid-sweep, brightening the last frames. Check moonrise and start in good time.
• Shooting too late, once the arch has climbed to vertical.

FAQ

Sources and further reading

• Wikipedia — Sagittarius A* (galactic centre position RA 17h 45m 40s, Dec −29° 00′ 28″, J2000; distance ~27,000 light-years).
• National Parks at Night — How to Plan, Shoot and Edit a Milky Way Arch Panorama (Part I) (season by hemisphere, ~50% overlap, vertical frames, levelling and nodal rail, shooting back to back).
• Capture the Atlas — How to Shoot a Milky Way Panorama (northern-hemisphere arch season February–July with the low arch late March–May; southern mid-January–late November; 50% minimum overlap; nodal rail only for a close foreground; stitching software).
• Lonely Speck — How to Find the Milky Way (galactic centre season mid-March to mid-October; low in the south from the northern hemisphere, overhead from the southern).
• EarthSky — Teapot of Sagittarius points to the galactic centre (core highest in the evening in August; overhead from the southern hemisphere).
• Julieanne Kost, Adobe — Creating Panoramas in Lightroom Classic (Spherical/Cylindrical/Perspective projections and Boundary Warp); PTGui — ptgui.com (paid; Windows, macOS, Linux); Hugin — SourceForge project (GPL, cross-platform); Wikipedia — Microsoft Image Composite Editor (retired 2021).