Thursday, 28 March 2013

Timelapse with the GH3

One of the new, fun features of the Panasonic GH3 is the timelapse mode. Sure, one could do the same thing with previous cameras as well, given that you buy an external controller to connect to the camera's remote shutter release socket. But having the timelapse possibility built into the camera is easier.

To make an example timelapse video, I first set the camera on a tripod over my table, like this:



I'm using the Manfrotto 190XPROB tripod, which is useful since the column can be set horizontally. The ball head is Benro B-2, but most ball heads can be used here.

I used the Lumix G 14-42mm f/3.5-5.6 kit zoom lens at 14mm, and set the aperture to f/3.5. This was done mostly to avoid the aperture closing and opening for each shot, which is a somewhat annoying ticking sound. I prefocused, and then set the camera to manual focus (MF), to avoid the camera engaging the autofocus mechanism for each shot. I also used the electronic shutter mode of the GH3.



Since I was planning to make a video from the timelapse, I set the aspect ratio to 16:9. And to avoid bogging down the memory card with too much data, I deselected the RAW option, and only used the lowest quality JPEG option, as indicated by the three blocks in the mode display below:



Setting up the timelapse is very easy. Just go to "Timelapse" in the Photo menu, and then set how often and how many images you want. I selected one image per every six seconds, and set a total of 1111 images:



I wasn't planning to use all the 1111 images, this just gave me enough slack, and I can stop the time lapse when finished. Then, it's just a matter of starting the timelapse.

I wanted to make sure the output images were scaled down to 1920x1080 and then sharpened using a sensible algorithm, so I used the ImageMagick tool "convert", in Linux. Converting all the JPEG images at once can be done with this command line:

$ find . -name "*.JPG" -exec convert -unsharp 0.5x0.5+0.5+0.008 -resize 1920x1080\! {} {}.PNG \;

The converted images are made into PNG images to avoid loss of quality in this process. To compose a video out of the still images, I used the program MEncoder, released together with MPlayer.

$ mencoder mf://*.PNG -mf fps=8:type=png -ovc x264 -x264encopts bitrate=24000:threads=2 -o video.mkv

I set 8 frames per second (FPS). And here is the output video:



In the time lapse, one can set a long delay between each shot, i.e., several minutes. If so, the camera enters a sleep mode between each shot. Setting manual focus still works, even if the lens focus is reset between each frame. Apparently, the camera has indexed the focus position.




10 comments:

  1. Steven Sullivan30 March 2013 at 09:49

    Another great article. I must say, I appreciate all your reviews and detailed comparisons -- they've been very helpful. And it's great to see a fellow photographer using Linux tools. Consider your hand shaken.

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  2. Thanks very much for sharing this. I'm curious when using the timelapse function on the GH3, what shutter speeds are available? Are you able to use slow shutter speeds or long exposures to create motion blur?

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    1. You can use any exposure mode in time lapse. So you can set the shutter speed manually if you want, to expose each frame for several seconds.

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    2. Thanks Fredrik. What is the range of shutter speeds, or exposure lengths available in the camera? How slow or long can you make the exposure in TL? For example, can it be in seconds, long enough for star-scapes? I've been trawling the net trying to find precise info on the shutter speeds available in the GH3 but haven't come upon. I'd appreciate your advice/experience with the camera.

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    3. I checked the camera just now. In the "M" manual exposure mode, you can set shutter speeds as slow as 60 seconds. The fastest shutter speed you can set is 1/4000s. All of the shutter speeds between these can be used in time lapse mode.

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  3. Thanks very much. That's an impressive range. After quite a hiatus from TL I was looking forward to getting into again with the GH3 (which I'm contemplating buying). All my previous has been on cameras with mechanical shutters, both film and digital so curious about the concept of an electronic shutter.

    Was also curious to read this today.

    http://timelapse.org/update-panasonic-gh3-intervalometer-problem/

    Would be curious to hear if issue now resolved. From your experience would appear so?

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  4. Ah, if you are interested in using the electronic shutter, then please note that the shutter speed range is not as large. The electronic shutter only works up to 1s shutter speeds, not slower. So to get the range between 1s and 60s, you need to use the mechanical shutter.

    The timing problems with the time lapse mode was fixed in the first firmware update for the GH3. So that should not be a problem anymore.

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  5. OK, so it has an electronic and mechanical shutter. I was unaware of that.

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    Replies
    1. Yes, it sounds like you should read a bit more about the electronic shutter of the GH3. It is not only positive news, I'm sorry to say.

      So unless you have a tripod, and only slow moving subjects, you have to use the mechanical shutter for the best quality.

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