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(sample photo)

I took this self portrait this morning getting out of the shower. There are some white squiggly lines: two near the sink and one on the door handle. What causes them?

The picture was taken with a Ricoh GR II (without flash). I'm very new to this, so maybe this is a no-brainer for a more experienced photographer, but I'm stumped and would appreciate any help.

  • EXIF Info please? – Itai Sep 6 '17 at 13:38
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    Read about light painting. You may start with squiggles, but a bit of practice and you can draw some pretty stuff. And it's fun. – Gallifreyan Sep 7 '17 at 18:50
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This image shows a rather long exposure.

The image in general is very dark, but a few spots are light. Probably some reflection on shiny surfaces like the door knob, the sink and the tap.

If you take a long exposure shot without a tripod you always move the camera around a bit. While it is not visible for the dark areas you can clearly see movement trails for any shiny spot.

The trails on the left are nearly identical. The trail in the center has less movement. Therefore you probably "shook" the camera and also rolled a bit.

Basically, what you did was something close to "light painting" but with moving the camera instead of the light source.

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When we take a picture, the camera lens projects an image on the surface of a light sensitive imagining sensor. The brightness of this image is important. If too dim, an under-exposure results and the picture will be too dark. If too bright, an over-exposure results and the image is washed-out. The camera’s software makes a determination as to how to ease this situation. If the scene is feebly lit, the software will call for a flash to augment the ambient light. If a flash is not available, the software will hold the shutter open long enough to allow light energy to accumulate on the image sensor. This is what happened! The shutter remained open in an attempt to achieve a better picture. During the extended time of the exposure, highlights (shiny spots of light from polished surfaces) recorded as squiggly lines.

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    nice answer, but i think it would be great to add at the end something like "...because of the movement of your hand whilst holding the camera.". This conclusion is not obvious to a newbie. – Sharky Sep 7 '17 at 6:43
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This is definitely a classic example of camera shake. To prevent this, there is a general rule of thumb when shooting at questionably slow shutter speeds: Your focal length (the distance from the plane of sensor/film to the first element of glass in the lens) should roughly equal the denominator of your shutter speed. For example, if you're shooting with a 100mm lens, your shutter speed should be no slower than 1/100th of a second.

  • While the general gist of your answer is definitely a truism, there are a couple problems with this answer. 1) Focal length is not defined as the distance from the plane of sensor/film to the first element of glass in the lens. 2) The rule of thumb is implicitly sensor-size-dependent. How does the rule of thumb work with a APS-C size sensor? What about Micro Four-Thirds? – scottbb Sep 18 '17 at 21:58

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