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For a oceanographic/atmospheric proof of concept project I need to set up a camera which will take a picture of the water's surface every 5 minutes during the day for up to two years. The pictures will be analysed and when conditions are right, other equipment will be turned on. I'd like a decent quality picture but I'd also like to keep costs low. The camera will be tethered via USB 1.1 to a machine running Debian Linux, so a camera supported by gphoto2 is a must. Decent low-light performance is a plus so we can see what's going on when the sun is low.

I was going to get a used Nikon D40 with the 18-55 off of eBay, but then I remembered that the rated shutter life of 50,000 actuations doesn't take long at this duty cycle.

A good P&S might work, but what to choose?

I've looked into webcams which do 1080, but the camera will be mounted up on a mast and the 3m maximum USB cable length is too short.

Anyone with suggestions?

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  • \$\begingroup\$ Are you mounting in some sort of weather-sealed enclosure? Do you need to account for powering the camera externally, too? \$\endgroup\$
    – D. Lambert
    Dec 7, 2012 at 21:27
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    \$\begingroup\$ I'm looking for something similar. So far, DSLRs seem problematic due to limited shutter life. How about using a smartphone as a webcam? You can choose between wifi and bluetooth for the tethering, and will only need a power source. Low-light performance won't be great, but it might be sufficient. And I don't know the life expectancy of a smartphone camera when used like this, it's probably slightly outside the design parameters :) \$\endgroup\$ Dec 7, 2012 at 22:29
  • \$\begingroup\$ I was going to get a PVC electrical enclosure and modify it to my needs. My USB cable will need to be about 5m. Power is not an issue as I've got plenty of wind and solar generating capacity. \$\endgroup\$
    – RyanN
    Dec 9, 2012 at 13:51

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I would look into hacking a GoPro camera/camcorder to use a continuous power source. The GoPro is very well suited to harsh environments, and already comes with a housing that could be utilized. Further, it is very reasonably priced. If you are serious about low light ability, the newest Hero3 Black Edition claims 2x better low light ability then the previous models and sensors. You can easily set them up to do timelapse, or shots every 5mins.

For more info about hacking one to work off a constant/hard wired power source, take a look at Google results. The first result seems to be a good example: http://www.jk720.net/post/9040461577/my-gopro-hard-wire-setup-and-remote-trigger-i

enter image description here

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  • \$\begingroup\$ +1, I like the weather proofing and image quality. For the Hero 3 Black Edition I don't think you need the power hack - according to the user manual, "you can charge the camera's battery while recording video or taking photos", so just leave it permanently plugged in. Two challenges: 1) The longest time lapse interval that can be set is 60 seconds, and I can't see a way to connect a third-party intervalometer. 2) The built-in wifi is only for remote control, it won't transfer files, so you'll still need a USB cable, some form of wireless USB, or some way to hack around the limitation. \$\endgroup\$ Dec 8, 2012 at 17:22
  • \$\begingroup\$ @j-g-faustus - The difference is that the linked to hack not only allows for hardwired power, but also control of the camera functions. With the Hero3 Black Edition specially, you can use the wi-fi remote, USB, etc - many options exist to extend this and so forth. The linked to hack will allow USB power, transfer, and control. The other limitation that you mentioned - only 60 second lapse maximum, is correct. But if the poster really needs every 5mins, then they could discard every 4/5 images I suppose on the hardware they are downloading to fairly easy. \$\endgroup\$
    – dpollitt
    Dec 8, 2012 at 18:15
  • \$\begingroup\$ A go pro would be ideal except for the write angle lens. It may be too wide. I've got a hero 2 I band do some tests with. \$\endgroup\$
    – RyanN
    Dec 9, 2012 at 13:53
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So I've decided to do the following:

I'm going to buy a used Nikon D40 kit with the 18-55 lens off of eBay for about $200. To power it I'm going to use a $9 Nikon EP-5 power supply connector and a 18W 12v to 9v buck converter I found for $4.

For communications, I'm going to try a $7 10m USB 2.0 Active Extension / Repeater Cable.

I'm going to modify a PVC electrical enclosure box to fit the camera and lens which I will then mount on a pole.

While I realize I'm somewhat limited by the D40's shutter life to be prepared I'm going to get a spare body. I've seen a few with broken flashes for under $100. I'm also going to try to limit my picture taking to when wind conditions are favorable. I've read that when getting Nikon to repair a shutter (~$200), you may be able to specify a new shutter with a longer rated life.

For software I'm going to use the following running on Debian:

I'll update this as the system is built if anyone is interested.

Feb 8, 2013 update:

I've mounted the camera in an enclosure I made and deployed it. I wish I had taken a picure of the box, but here's the first picture I took with the camera using python and gphoto2: Neuse River Estuary It's been raining, so there are some drops on the enclosure window. That black shape in the lower right is a wind generator blade. Those streaks on the water are the phenomenon we are going to study. I'm currently refining the time lapse software. No need to take pictures when there isn't enough light.

March 5, 2013 update: Have had problems with the usb port locking up and I now reset it before every picture. I've added an overlay to the picture to make it easier to analyse later. The overlay is added using PIL.ImageDraw. Unfortunately, this strips the exif data, so I'm saving that to a text file. I'm also using paramiko to sftp the file back to my office right after it's taken and delete the local copy to save disk space. We're also thinking that a low-res time lapse between pictures would be useful. To this end, I was able to do a image_capture from an old webcam using streamer. I may now add a webcam to my enclosure with it's own window and do a capture every 5 seconds. Picture with annotation February 26, 2014 update: I'm still very happy with how this has worked. The shutter count is 38,000 so we're reaching the camera's design rating. We'll see how much longer it goes. enter image description here

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  • \$\begingroup\$ I think you are making a mistake getting a camera with a mechanical shutter. The D40 and similar SLRs are not designed to continuous use in a humid environment. If you don't have available expertise (I don't mean someone who has never done it but thinks they know how) at encapsulating equipment for this environment, you are asking for problems sooner than you think. You must know that your sealed PVC box may appear to do a good job keeping water out (it won't 100%), but experience shows that is will also keep water in. Think about how water inside your box will affect your D40 in the sunlight. \$\endgroup\$
    – Jim
    Feb 8, 2013 at 18:00
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    \$\begingroup\$ While I do have some concern over the life of the shutter, the environment doesn't worry me. I've got a great deal of experience building enclosures for equipment in harsh environments, including submerged electronics. The enclosure I built (PVC welded with watertight cable glands) could probably survive submersion to a meter. Which should be fine mounted on a pole 3m in the air. In addition, there is a great deal of desiccant in with the camera. I sometimes put humidity sensors in with more valuable equipment, but I'm not too worried. \$\endgroup\$
    – RyanN
    Feb 8, 2013 at 19:20
  • \$\begingroup\$ Sounds good. You didn't mention how often you will service it. What is your plan on that? \$\endgroup\$
    – Jim
    Feb 8, 2013 at 19:25
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There are devices available which will extend USB substantially while maintaining a USB output.

You can do USB to TCP/IP using any of many low cost microcontroller boards.

You can translate USB to wiFi 802.1... and then need feed only power.

You may be able to use solar powering and need no cables.

The Canon A series Cameras, are aVailable at a good price new and used. Superb free software named CHDK (Canon Hack development kit) is available. This loads from the SD card slot at power up and allows many features to be combined in new and interesting ways. This software will not work on many of the latest A series cameras, but works on many of the older ones. The software would easily meet your time lapse requirement. CHDK: - and CHDK tutorial here

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  • \$\begingroup\$ I've seen USB to cat5 converters but they either only do USB 1.1 or are expensive. USB to wifi is worth looking in to a I already have wifi capabilities. \$\endgroup\$
    – RyanN
    Dec 9, 2012 at 13:56
  • \$\begingroup\$ There's also wireless USB extenders, around $400. The advantage over USB to IP (or WiFi) is that it's hardware only and thereby OS agnostic, it doesn't need a dedicated driver on the PC. \$\endgroup\$ Dec 9, 2012 at 16:10
  • \$\begingroup\$ For the USB connection, I'm going to try a 10m Active Extension / Repeater Cable from monoprice. For under $7 it's worth a try. \$\endgroup\$
    – RyanN
    Dec 18, 2012 at 20:10
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Brinno make a specialized time-lapse camera for $149 Sold by Photojojo and others

  • weather resistant (don't have to risk your SLR getting soaked)
  • has normal and macro lens setting macro is about 19" or .5m
  • six standard time settings of 1 minute, 5 minutes, 30 minutes, 1, 4 and 24 hours
  • one custom time setting you can program anywhere between 5 seconds and 12 hours

battery life (4 AA)

  • @5 second setting, will capture 28000 frames over 38 hours
  • @24 hour setting, will capture 200 frames over 200 days
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How is your project going ?

Using gphoto2 as you mentioned is a very good way to go.

We are doing something similar here: http://www.webcampak.com

On my side I would suggest to avoid using USB extenders (long term reliability). What you could do is use an embedded computer (or a Raspberry PI) with a Wi-Fi (or Ethernet) to your home.

It will slightly increase your costs, but it's likely to increase reliability.

In terms of actuations, I would recommend to go for a new camera, the issue with second hand, is that you never know how it was taken care off. For a dev platform we once bought a second hand camera, and it failed at 40 000 shots, where our standard setups with low-end Canon models (T2i, T3i ...) bought new usually reach close to 300 000 shots.

I hope it helped.

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  • \$\begingroup\$ I've purchased a used Nikon D40 and an 18-55 lens. I'm currently building a weatherproof enclosure for it. This is somewhat a proof of concept so if it works, and I get more funding, I could see a newer camera, but a clean DSLR for $110 isn't a bad deal. The USB2.0 extender I bought seems to work well and the ends won't be exposed to the environment. We already have an embedded Atom PC/104 with a 3G modem aboard our floating platform, and while I see the benefit of a Raspberry pi controling the camera, I think I'll try the 30' USB cable for now if only to stay within my power budget. \$\endgroup\$
    – RyanN
    Jan 28, 2013 at 19:14
  • \$\begingroup\$ You are right, a DSLR for 110$ can be a good deal :) At the end it all comes down to reliability. If you are lucky your camera will last, if not you might find another 110$ camera and still be lower than the cost of a full camera. In some of our setups we need to rent a cherry picker to access the camera, at 400e per 1/2 day we try to avoid using that to often therefore using only brand new cameras :) \$\endgroup\$
    – Francois G
    Jan 28, 2013 at 23:33

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