Guides · Updated 4 November 2026
Common Tern photography: shutter speed, lens and crop for common terns in flight
The numbers for photographing a Common Tern in flight, worked out from published wingspan, flight-speed and wingbeat figures: the shutter speed that freezes the wingtips and the body, how many pixels the spread wings fill with 400, 600 and 800 mm lenses at 10, 25 and 50 m, and how far away the bird can be for a 2,048-pixel image or an A4 print.
Short answer: pan with the tern in flight, or catch it hovering, and its body stays put in the frame, so the wingtips set the shutter speed. With its wings across two thirds of the frame on a Canon EOS R7 and 600 mm lens (about 33 m away), 1/2000 leaves the wingtips about 28 px of blur mid-stroke, and keeping them sharp on screen (3 px) takes about 1/20000, beyond the 1/8000 top speed of most mechanical shutters. A burst catches them: at 1/2000, about 1 in 15 frames have the wingtips within 3 px, about 1.3 frames a second at 20 fps. Held still instead, the camera needs about 1/25600 to keep its body within 3 px as it flies across; when it hovers, its body barely moves, so only the wingtips count. At 25 m with 600 mm, its wings span 3,206 px on a 24-megapixel full-frame body and 5,986 px on the 32.5-megapixel R7.
Shutter speed for common terns in flight
From our shutter-speed calculator with its default setup: a Canon EOS R7 (32.5 megapixels) and a 600 mm lens. You pan with the bird (or it hovers), so its body stays put in the frame and the blur that's left comes from the wings, each taken to sweep a 100° stroke at the bird's wingbeat rate, fastest mid-stroke. Blur is counted in the photo's own pixels at 100%: up to 3 pixels is sharp on screen, 1 pixel is pixel-sharp. The camera-still column is for a bird crossing in front of a camera that doesn't move, at its cruising speed.
| Canon EOS R7, 600 mm | Wingtip blur at 1/2000, panning | Wingtips sharp on screen (3 px) | Body sharp on screen, camera still (3 px) | Frames with the wingtips within 3 px at 1/2000 |
|---|---|---|---|---|
| Wings across two thirds of the frame, about 33 m | 28 px | 1/20000 | 1/25600 | about 1 in 15 |
| Wings across a third of the frame, about 64 m | 15 px | 1/10000 | 1/12800 | about 1 in 8 |
Its wingbeat rate is an estimate (sources below), so treat these as close guides rather than exact figures. Holding the wingtips pixel-sharp (1 px) with its wings across two thirds of the frame would take about 1/57,000. The wings stop for an instant at the top and bottom of each stroke, which is why a burst catches sharp wingtips that a single frame usually misses. Stepping back until the wings span a third of the frame halves the blur; crop in afterwards.
Pixels across the wings with 400, 600 and 800 mm
Pixels across the spread wings at 10, 25 and 50 m, from our reach calculator, on a 24-megapixel full-frame Canon EOS R6 Mark II, a 45.7-megapixel full-frame Nikon Z8 and the 32.5-megapixel APS-C Canon EOS R7:
| Distance | Lens | Canon EOS R6 Mark II | Nikon Z8 | Canon EOS R7 |
|---|---|---|---|---|
| 10 m | 400 mm | 5,432 px | 7,474 px | won't fit |
| 10 m | 600 mm | won't fit | won't fit | won't fit |
| 10 m | 800 mm | won't fit | won't fit | won't fit |
| 25 m | 400 mm | 2,120 px | 2,917 px | 3,958 px |
| 25 m | 600 mm | 3,206 px | 4,411 px | 5,986 px |
| 25 m | 800 mm | 4,309 px | 5,930 px | won't fit |
| 50 m | 400 mm | 1,051 px | 1,447 px | 1,963 px |
| 50 m | 600 mm | 1,583 px | 2,179 px | 2,957 px |
| 50 m | 800 mm | 2,120 px | 2,917 px | 3,958 px |
“Won't fit” means the wings are wider than the frame at that distance. The sum: wingspan × focal length ÷ (distance − focal length) gives the wings' size on the sensor, divided by the pixel pitch (5.98 µm on the R6 Mark II, 4.35 µm on the Z8 and 3.20 µm on the R7). Halve the distance and the pixels roughly double.
How far can you crop?
Most size rules count pixels on the long edge. An image 2,048 pixels wide can come from as little as 35% of the R6 Mark II's 6,000-pixel width, 25% of the Z8's 8,256-pixel width and 30% of the R7's 6,960-pixel width. A landscape A4 print at 300 ppi (29.7 × 21 cm) needs 3,508 × 2,480 pixels: 59% of the width and 62% of the height on the R6 Mark II, 43% of the width and 46% of the height on the Z8 and 51% of the width and 54% of the height on the R7.
Framed the way the reach calculator frames a crop, with the wings across half its width, here is how far away the tern can be and still give you each size, cut from the full-size original with nothing enlarged:
| Camera and lens | Image 2,048 px wide | A4 print at 300 ppi |
|---|---|---|
| Canon EOS R6 Mark II, 400 mm | up to 51 m | up to 28 m |
| Canon EOS R6 Mark II, 600 mm | up to 76 m | up to 42 m |
| Canon EOS R6 Mark II, 800 mm | up to 100 m | up to 56 m |
| Nikon Z8, 400 mm | up to 70 m | up to 38 m |
| Nikon Z8, 600 mm | up to 100 m | up to 58 m |
| Nikon Z8, 800 mm | up to 140 m | up to 77 m |
| Canon EOS R7, 400 mm | up to 95 m | up to 52 m |
| Canon EOS R7, 600 mm | up to 140 m | up to 79 m |
| Canon EOS R7, 800 mm | up to 190 m | up to 100 m |
With its wings across a third of the R7's frame (about 64 m at 600 mm), a crop with the wings across half its width is 4,608 × 3,072 pixels, a 39.0 × 26.0 cm print at 300 ppi. These distances count pixels only; at long range, heat haze and focus cost detail too. Crop from the full-size original, never from a downsized export, and never enlarge a crop to reach a size (how much you can crop a bird photo).
Try it with your own camera
The shutter-speed calculator opens set to the Common Tern, and the reach calculator to its wingspan; change the camera, lens or distance to see your own numbers. Guides for the bodies above: Canon EOS R6 Mark II, Nikon Z8 and Canon EOS R7. To see how a crop looks on one of your own photos, try the free online cropper.
BirdFrame for Mac finds every bird in a folder or Photos album and crops each from the full-size original, thousands at once, so a day of bursts doesn't mean cropping by hand.
Sources
Common Tern: wingspan 0.78 m (All About Birds); cruising speed 11 m/s (Pennycuick et al. 2013); 4.6 wingbeats a second (est. from size and weight, Pennycuick 1996).
Camera sensor sizes and pixel counts are the makers' published specifications. Every bird is taken to beat its wings through a 100° stroke (est.; 80–130° depending on speed, Park et al. 2001). Values marked est. are estimates.
Questions
What shutter speed freezes a Common Tern in flight?
Pan with the tern in flight, or catch it hovering, and its body stays put in the frame, so the wingtips set the shutter speed. With its wings across two thirds of the frame on a Canon EOS R7 and 600 mm lens (about 33 m away), 1/2000 leaves the wingtips about 28 px of blur mid-stroke, and keeping them sharp on screen (3 px) takes about 1/20000, beyond the 1/8000 top speed of most mechanical shutters. A burst catches them: at 1/2000, about 1 in 15 frames have the wingtips within 3 px, about 1.3 frames a second at 20 fps. Held still instead, the camera needs about 1/25600 to keep its body within 3 px as it flies across; when it hovers, its body barely moves, so only the wingtips count.
How many pixels does a Common Tern fill with a 400, 600 or 800 mm lens?
Across its 0.78 m wingspan at 25 m, on a 24-megapixel full-frame body: 2,120 px with 400 mm, 3,206 px with 600 mm and 4,309 px with 800 mm. On the 32.5-megapixel Canon EOS R7: 3,958 px with 400 mm and 5,986 px with 600 mm; with 800 mm the wings are wider than the frame. Halve the distance and the pixels roughly double.
How far away can a Common Tern be for a 2,048-pixel image or an A4 print?
With the wings across half the crop's width, as the reach calculator frames it: with 600 mm on a 24-megapixel full-frame body, up to about 76 m for a 2,048-pixel-wide image and 42 m for an A4 print at 300 ppi; on the Canon EOS R7, 140 m and 79 m. Crop from the full-size original and never enlarge a crop to reach a size.
Crop every bird in one go, at full resolution. BirdFrame finds the birds in a whole album or folder and crops each one from the full-size original. Free for up to 50 photos per run.