I've purchased my magnets here and the ferrous mounting stripes here. I've used UV cure superglue for attaching the magnets, as standard superglue sometmes failed after longperiod of being wet.

Just be aware of the limitations; you'll be transmitting at a very slow baud rate on frequencies that may have strict duty cycle (transmission time) and ERP (transmission power) limits. Check up on the rules for the region in which you intend to operate and make sure that the restrictions fit in with your intended application.

The following two papers describe our attempst to develop an open source RPi camera trap platform with long range communications capability, and may be of interest:

Nazir, S., Fairhurst, G., Verdicchio, F., 2017. WiSE - a satellite-based system for remote monitoring. Int. J. Satell. Commun. Netw. 35, 201–214. https://doi.org/10.1002/sat.1176

Nazir, S., Newey, S., Irvine, R.J., Verdicchio, F., Davidson, P., Fairhurst, G., Wal, R. van der, 2017. WiseEye: Next Generation Expandable and Programmable Camera Trap Platform for Wildlife Research. PLoS One 12, e0169758. https://doi.org/10.1371/journal.pone.0169758

More details can be found here: https://erg.abdn.ac.uk/wise/

/Scott

Vasudev

I have had no issues using ubiquiti device and pushing internet out to 5 miles line of site, what I am curious what are you using for you camera on the other end, I have always wanted to try and build a long distance wifi trail camera ( true wifi ).

is it solar powered or battery powered that has been my issue trying to figure out the power issue 

Hey Ellie--

Glad to see you getting started with this. 

I'll speak to the data-storage question, it might be worth it for you to do something like paying for extra google drive space rather than go through the external hard drive process. That way you're ensuring you don't have to worry about losing your drive or just leaving it at home. It's $30 US for 200GB of space for a year, which is quite reasonable, especially for a single recorder / camera trap. 

I'd also make sure you have an SD card reader, and maybe a sealed card holder/wallet to keep data safe while it transitions from the field. How much to budget for batteries will depend on exactly what sensors you end up purchasing but in my experience, ordering high-end alkaline batteries is the best bet (for example, in the Duracell line, their Procell D batteries really do perform better than the normal consumer level coppertop batteries). I'd recommend playing around with the scheduler software for whatever acoustic sensor you end up obtaining to figure out whether you'll be limited by power or storage depending on how you set things up.

Oh very cool Robin. Do you mind if I ask how much it is for the unit?

Thank Capreolus,

for your feedback, did you try it where the cellular network is weak? 

Thank you.

much appreesh @StephODonnell 

@Freaklabs 

Akiba may be interested?

I think it would be technically possible. Something like the camera being put to sleep, and only activated when an outer sensor is triggered. I would be more worried about getting ethical approval for such a study where the aim is to have a live domestic animal being attacked by a predator in a confined space.

My guess is that the camera triggering will prove to be far less of a challenge than getting ethical approval for penning livestock where predators can reach them. If you have such a high rate of wolf attacks in free-ranging flocks then you can directly measure the decrease in rate of attacks in flocks that have the repellent vs those that do not. 

Hi Ivonne,

Have you considered using a GOPRO? They have some pretty natty features now  and they have a good range of mounting and waterproofing gadgets. If you don’t need traditional camera trap features these work well and you can dial up the image quality to suit your needs.

Dave 

Do you need the photos during the timelapse, or just all at once at the end?  If the latter, how many exposures will you need per timelapse recording?  Depending on your answers, that might limit you to only options that let you retrieve images during recording - perhaps requiring wifi or celular?

Not knowing your requirements there, just some general thoughts:

GoPros

I too would think a GoPro would be an option, iff wide angle suits your purposes (though, if resolution isn't a high priority, GoPros do have exposure-time cropping options).  Cheap, robust, with myriad accessories easily available.  They also have wifi support - though, last I checked, you can't browse & download images while the GoPro is in recording mode (not even between exposures).  Maybe newer models have removed that limitation?

There's also relatively novel options like the GoPro MAX with 360° video recording.

Trail cameras

I've used several different trail cameras that have timelapse options - they're pretty common.  I haven't used Reconyx ones, though.  In general I find trail cameras to be pretty useless photographically - fine, maybe, for just monitoring wildlife activity.

Mirrorless / DSLR

If you do go for a 'real' camera, go for one with (at least the option of) a pure electronic shutter.  Few DSLRs have this option.  Some - but not all - mirrorless do.  Mechanical shutters (a) can cause motion blur and (b) tend to break after a few hundred thousand exposures.  e.g. if you're doing one exposure per minute, you'd get less than a year from most consumer cameras.

The Sony a6100 (or later) cameras are good options for this - they're old and therefore can be found very cheap, but the image quality is still light-years ahead of trail cameras & GoPros.

A slightly more up-market option - probably only of any interest if night-time exposures are important - would be a Nikon Z5.  Alas they're current-model so you probably won't find big discounts, but you get:

• Excellent image quality (provided 24MP is sufficient resolution for you - are you aiming for 8K timelapse?).  There are higher-end options (Z6, Z7) as well as Sony a7r options if you need higher resolution or (marginally) better image quality.

• The ability to use practically any lense ever made on them (their Z mount supports adapters to practically any other mount system).  In case you have particular lens requirements, or existing lenses you want to use.

• Twin UHS-II SD card slots, so you can record to two cards simultaneously if data loss (from a faulty SD card) is a concern.

Keep in mind, though, that most mirrorless/DSLRs have limitations on how many exposures they'll allow on their built-in intervalometers (e.g. 9999 for Nikons).  But there's usually ways around that using $10 plug-in intervalometers, if need be (and fancier options if you want more control, such as "bulb ramping" for recording across day & night smoothly).

Hi Ben,

This is relatively straightforward. It just requires an IP network camera, a 12V PoE injector, 12V power source, high-capacity SD card and an ethernet cable to your laptop.

I designed and put this ruggedized system together in a Pelican case for outdoor use. It may interest you:

https://envirocam.com.au

Various lenses from 2.8mm (wide-angle) to 16mm (close-up) can be used for or even thermal for complete visibility in darkness. Up to four lenses can record simultaneously for multiple angles of view.

Whist used for illegal-dumping detection in bushland, it can be equally used for your scenario.

I'm happy to give you some pointers - just reach out.

Best regards,

Anthony

I would suggest, if time is of the essence, to use an off-the-shelf "security" camera.
I had some luck using Wyze cams, they are $35 apiece and connect via wifi. You power them via USB and it should be easy to set up either a large car battery with a usb charger or even a simple solar setup with a 5V output. The new version is weatherproof, although it would probably require further waterproofing for a rainforest setup. They are fairly small (I think something like a 5x5x5cm cube) and have visual motion detection, something that would be of benefit for your as it would also pick up reptiles as they move into the frame. They a microSD slot and you can view the data remotely, the app will send you notifications every time there is a movement detected. They are not in real-time but usually with less than a minute delay and for a couple of $$ a month you get unlimited cloud storage as well.
As mentioned earlier, of might be easier to run a camera on wire and power it with PoE, the connection would be much more stable but then you need to have a physical connection and a cable running through the forest which is another challenge.
Just my $0.02, keep in mind this is not as robust of a solution as, let say, envirocam, but it will allow you to set it up really quickly, given you have internet access.

Could you explain a bit more, do you want a measurement of length, or whole volume?

Like @wkcmark said, there are some simple solutions for measuring length fish, using stereo arrangements for example (2 cams looking at the same spot from slightly different angles). I also found this creative solution, using a single camera in a special acrylic case, that makes use of refraction indices. This, again, is for underwater systems.

If you could project two lasers at a known angle on the body of the animal like in exploration submarines, you could calculate the distance from the camera and measure the animal, although this would be a manual process.

The simplest version might be a laser rangefinder, a measurement of image size, and some straightforward geometry, whihc would allow reasonable calculations of linear measurements. 

I've been wondering about rangefinding/size-measuring technologies that could be incorporated into camera traps for a long time, and am following this thread and the work of @Freaklabs with great interest.

So far I see there's stereo photography, Lidar, structured light/illumination, laser rangefinding, being suggested. I'm curious if we could come up with a relatively exhaustive list of potential technologies, then possibly discuss the pros/cons of each when used in a camera trap? For example, laser rangefinding might give precise and accurate measurements but maybe because it is an active sensor it drains the battery quickly and the laser might affect animals?

If there's interest I can start a separate thread so as to not detract from this one.