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I am trying to make timelapses all day and night long using gphoto2. I am making a picture every 2 minutes.

When looking to the results at night, I see very black pictures, sometimes there are some stars on it. When looking to the exposure, I see it has a max of 3 seconds (at ISO 1600).

I set auto ISO to a max of 1600. I used the 'A' mode, with a diaphragm of 4 (my lens is a 35mm lens). I use spot metering. The spot that is measured is somewhere on a mountain without any lights. Autofocus is off.

Last night I also tried 'P' but that does not make it any better. It is maybe even worse, the max ISO is now 1100 and the max exposure 1s.

Why is my camera not using the min exposure of 30s when it is so dark? Is there a way it can do that without setting the exposure manually? Does anyone have any idea? I did not find a setting to control the min exposure time when set to auto exposure.

Added an image here but it is just pitch black. :P I don't know if the exif data is still included here.

Picture of last night

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  • \$\begingroup\$ have you tried any other ways? what about the internal intervalometer (Interval timer shooting on the d5000)? Using the latter, A mode, stopped down, and try fixing the ISO at a low number (and Auto off). The camera will adjust the shutter speed. \$\endgroup\$ Mar 12 at 20:40
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    \$\begingroup\$ Yes we tried manually a lot of different settings with a Nikon D5100 but it shows exactly the same results. So it is something in the software, I just can not understand what exactly happens and find any settings related to this etc. \$\endgroup\$
    – Maaike
    Mar 13 at 9:43

3 Answers 3

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I've never used gphoto2, so have no idea about its capabilities. My answer assumes stand-alone use. Your software might have similar functionality.

It's standard fayre that the auto timer only goes to a few seconds. After that you have a 'bulb' setting that will stay open as long as the shutter release is held - which is a recipe for shaky photos, even on a tripod.

The cheap way round this is to get a remote with timer from eBay etc. There are a myriad of them, all cost next to nothing. eBay UK search for 'remote shutter timer' They come with interchangeable plugs on the end, pick one for Nikon. You can dial the exposure time into the remote & not have to touch the camera at all, so no shake.

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  • \$\begingroup\$ Well with gphoto2 I can also set the exposure etc. But what you say is that auto exposure will never be 30 seconds, but only like 1 or 3? Only if you set it manually? No you don't need to have knowledge about gphoto2, I was only mentioning it to show my setup. But the problem is actually that when setting the camera to 'A', the exposure never goes to more than 3s, despite it is very dark outside :(. I do not understand why it is 'stuck' at a maximum of 3 seconds. \$\endgroup\$
    – Maaike
    Mar 10 at 13:45
  • \$\begingroup\$ This type of shot is one I'd be doing in full manual anyway. I've done very long exposure with my remote, but never tried in Auto, so i'm not really sure how I'd expect it to behave, tbh. \$\endgroup\$
    – Tetsujin
    Mar 10 at 16:29
  • \$\begingroup\$ If an exposure sensor would receive 1,000 units of light for what would normally be a 1/100-second exposure, reducing the amount of light by seven f-stops would mean that it only received about 8 units of light, for about a one-second exposure. If the sensor has about +/-2 units of uncertainty, that wouldn't be any problem under the brighter conditions, and would even be tolerable in the lower light conditions, but the sensor would become less and less usable at lower light levels. \$\endgroup\$
    – supercat
    Mar 10 at 19:43
  • \$\begingroup\$ Yes @supercat, it looks indeed like that's the case. We played a lot with it but the camera can't just do it, can't measure well enough maybe. \$\endgroup\$
    – Maaike
    Mar 13 at 9:32
  • \$\begingroup\$ @Tetsujin no normally you do this kind of things manually indeed, but we now have a timelapse of half a year, so doing stuff manually is not really a good idea :D. Maybe we can do something with software, don't know yet. \$\endgroup\$
    – Maaike
    Mar 13 at 9:34
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Why is my camera not using the min exposure of 30s when it is so dark?

If it's so dark that it takes more than three seconds (maybe a lot more than three seconds) to take a well-exposed photo, how is the camera going to judge the incoming light to decide on the right exposure, within the tenth of a second or so that the auto-exposure takes? All it knows is that it's dark. Really dark. The difference between "so dark it needs a 10s exposure" and "so dark it needs a 30s exposure" is below the noise level of the sensor — at least until you expose for around 10 seconds.

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  • \$\begingroup\$ It indeed looks like the camera just takes a maximum amount of light, kind of (so for example when at is this dark, it will do something with iso 1600, aperture 4, exposure 4 seconds). If you increase iso with a certain amount of stops, it will just add that amount of stops to exposure (if you set the camera to 'A'), so the ratio between them will stay the same. \$\endgroup\$
    – Maaike
    Mar 13 at 9:31
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With some Nikon cameras you need to be in shutter priority (S), or manual mode (M), to access the extended exposure settings (down to 30").

The extended shutter speeds are also available to program auto mode, but only at certain ISO settings. The auto exposure program is shown in the manual (p.126); but it doesn't really clarify much of anything.

For exposures longer than 30" you need to use manual mode. After the 30 second setting there are two options, "bulb" and "time" (indicated by - -). In bulb mode the shutter stays open as long as the shutter release button is held. In time mode the shutter remains open until the shutter button is pressed a second time. Use of a remote release is recommended for both.

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  • \$\begingroup\$ Well I have seen it going to 30 seconds, if you for example set aperture to 11, and iso to 400, it will set the exposure to 30 seconds. But as soon as you for example set aperture to 4 and iso to 1600, it will set the exposure to like 3 seconds or something. So it looks if it is too dark, there is a certain 'max number', which is a combination of those settings (so if increasing exposure with 1 step, the aperture will be decreased with one step). \$\endgroup\$
    – Maaike
    Mar 13 at 9:41
  • \$\begingroup\$ @Maaike; Like I said, the combination of settings auto program will use is on p.126 of the manual. And it does seem to include 30"... \$\endgroup\$ Mar 13 at 12:23
  • \$\begingroup\$ Interesting graph. Will look into that one in detail later but I don't think it clarify's this indeed. \$\endgroup\$
    – Maaike
    Mar 14 at 9:01

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