The International Space Station crosses the evening and morning sky as a bright, steady point of light, often brighter than any star. On camera it becomes a clean streak across the frame, and with good planning you can place that streak over a skyline, a tree line, or a mountain ridge. This guide covers how to find a pass, how to frame it, which settings record the full arc, and how to stack frames when a single exposure is not long enough.
Finding a Pass Worth Shooting
The station is only visible when it is lit by the sun while your location is in darkness, which happens shortly after sunset and before sunrise. Pass prediction apps and astronomy websites list the start time, the direction it appears from, the maximum height above the horizon, and the direction it disappears. A pass that climbs high in the sky is brighter and longer than one that skims the horizon, so prioritize those.
Note the exact start time and the compass directions. Most passes last a few minutes from first sight to fade out, and some end abruptly as the station enters the earth shadow, which can give your streak a neat ending in the middle of the sky. Check the weather and the moon phase too, because a bright moon or thin cloud lowers the contrast of the trail.
Framing the Arc Over a Foreground
A wide lens lets you record most or all of the arc in one frame. The station travels quickly, so a long lens will only capture a short section. Plan where the station will enter and leave the frame using the compass directions from the prediction, and place a foreground subject so that the streak curves above it. Buildings, trees, and ridgelines all work, and a small amount of ambient light on the foreground adds depth.
Use a sturdy tripod and set the camera before the pass begins, because you will not have time to adjust once the light appears. The articles on finding a dark sky site and light pollution settings help you pick a location where the streak stands out, though the station is bright enough to photograph from most towns.
Settings That Record a Clean Streak
Set manual focus on a bright star or a distant light using magnified live view, then switch the lens to manual. Start with a moderate aperture to keep the stars sharp, a low to moderate ISO, and an exposure long enough to capture a good length of the streak. A thirty second exposure is a common starting point, and the camera will record the station moving across a section of the frame during that time.
Set the camera to continuous shooting with a remote or intervalometer so that each exposure starts immediately after the previous one ends. That way, the station draws a continuous line across a series of frames. Turn off long exposure noise reduction, because it inserts a gap after each frame equal to the exposure length, which will break the streak into pieces.
Brightness of the trail depends on aperture and ISO, not on exposure length, because the station spends only a moment over any one patch of sensor. Opening the aperture a stop makes the streak bolder, while a longer shutter only adds more sky glow and more stars. On a town sky with heavy glow, shorten each frame to fifteen or twenty seconds and simply shoot more of them.
Stacking Frames to Join the Full Arc
A single exposure rarely covers the whole pass, so you will usually combine several frames. Stacking software or a lighten blend mode in an editor layers the frames and keeps the brightest pixel from each, which joins the streak segments into one unbroken arc. The technique is the same one used for star trails, and the guide on stacking without visible gaps covers how to avoid small breaks.
- Keep the camera untouched between frames so they align perfectly.
- Shoot a few extra frames before and after the pass for clean sky.
- Use the same exposure for every frame to avoid uneven brightness.
- Remove aircraft trails that cross the frame by masking them out.
A Worked Example and a Common Mistake
Picture a high evening pass rising in the west and fading into the earth shadow in the east. The photographer sets up near a lighthouse with a wide lens, focuses on a bright star, and starts a continuous run of thirty second exposures a minute before the predicted start time. Five frames capture the whole streak, and stacking them produces a clean arc that ends abruptly above the lighthouse as the station slips into shadow.
The most common mistake is starting too late. The station appears suddenly near the horizon, and photographers who wait to see it before pressing the shutter often miss the first part of the arc. Start the sequence a minute early and let it run until well after the predicted end.
Frequently Asked Questions
It is often one of the brightest objects in the night sky, brighter than most stars and planets during a high pass. Brightness changes with the height of the pass and the angle of the sunlight on its panels.
No. The station moves much faster than the stars, so a tracker does not help. A fixed tripod and a wide lens are all you need.
You can capture a short section of the streak, or with specialist tracking setups, detail of the structure itself. For a beginner, a wide lens that captures the whole arc gives a more reliable result.
Gaps usually come from long exposure noise reduction or a delay between frames. Turn noise reduction off and set the intervalometer to start each exposure immediately after the last one.
Passes happen throughout the year, but visibility depends on your latitude and the season. Check a prediction tool regularly, since good evening passes come in clusters every few weeks.
The Short Version
Use a pass prediction to choose a high, bright pass, frame the arc with a wide lens over a strong foreground, and run continuous long exposures without gaps. Start early, stack the frames with a lighten blend, and you will have a clean streak across the sky.