One hundred milliseconds guaranteed: where long exposure ends on a phone
The shutter dial stops where the hardware says it stops. What the Android and Apple camera APIs actually promise about your phone's exposure ceiling.
Read →3SIGNUM: smartphone astrophotography
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Magnitude 3.4 and invisible: the number the catalogue leaves out
Andromeda is magnitude 3.4 and it still refuses to show up from your garden. Surface brightness explains why nebulae vanish and stars don't.
Thirty degrees up: altitude is a camera setting
At thirty degrees the light crosses twice as much air, at ten almost six times as much. Why your target's altitude decides the shot more than any setting.
Two and a half millimetres of light: a phone at the telescope eyepiece
A disc of light 2.5 mm across floats above the eyepiece, and the camera has to sit inside it. The arithmetic of scale, brightness and alignment.
Three cameras, and the phone does the choosing: which lens actually works after dark
The zoom button isn't wired to a lens. What really decides which sensor shoots, why it can change its mind halfway through a run, and how to take the wheel.
ISO is not a light switch: how much gain a dark sky actually needs
Gain is applied after the photons have been counted. What the ISO slider really changes, where analogue amplification stops, and how far to push it.
Four pixels into one: why twelve megapixels beat fifty after dark
Your phone adds its photosites up in fours before handing you a file. What that buys you, and why full resolution at night is a poisoned gift.
