periodic pictures and remote retrieval

jcarrr

3

« on: 10 / January / 2013, 21:20:07 »

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Hello,

I need to tap into the collective stream of imagination and knowledge. Our company routinely collects data from a number of unattended sites that monitor flow, pressure, levels, etc. We need to collect high quality photos from some sites that will be individually examined each day to determine that we are not causing a flood, have not been vandalized and the station is not on fire. The links link to the net by 802.xxx.xx channels, cell modems and by satellite up-links.

I don't seem to be able to get my mind around a good way to reliably get acceptable photos. The crummy little camera I carry around in the glove box of my pickup takes pictures that would be perfectly acceptable. Still frame grabs from video monitors are not acceptable. If the system takes a couple of photos per day, a card would last a long time.

I realize the Sony DSC-S650 lying on my desk is not a candidate for CHDK, but it has features I am familiar with. Other cameras are easy to find.

This camera would be fine if:

It could be powered through the USB connection (as opposed to trying to power the USB system with the 2 AA batteries in the camera).

The bulk storage card file system was accessible while the camera was in a mode where pictures could be taken and stored.

Picture taking could be triggered on a schedule, or better, triggered by a remote command.

The jpg image would be fine. With access to the file system as discussed above, the local controller coordinating the facility can FTP the images to the remote server at a data rate that does not overwhelm the channel.

Perhaps the camera already exists and I have not found it. It may be acceptable to gear up and build them. We might use a hundred of them.

Do these cameras have a life time if they are powered up for a couple of years?

If they get cold and quit working ( know mine does) will they come back to life when it warms up?

Is it possible to hack current production cameras? Expected in the future?

Recommend a camera? It would be nice if well intentioned non tech wrench wielders could change out inoperative units, so a simple system is better. Expensive cameras are not out of the question, but I doubt they would meet the need any better than the point and shoot type.

I am not opposed to programming and hay wiring devices, we are pretty good at it, but, if there are cameras that meet the criteria without modification, point me at them.

Please, any and all constructive thoughts are welcome.

jc

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waterwingz

12138

Re: periodic pictures and remote retrieval

« Reply #1 on: 10 / January / 2013, 22:09:59 »

From the looks of it, you are going to need a CHDK camera and some sort of computer node. A Raspberry Pi would be more than adequate. You can get external power supplies for all Canon p&s cameras. You might want to plug everything into a UPS or at least some sort of power conditioner.

With the kit listed above, something like chdkptp with a simple script Lua script on the computer node could trigger shots on a schedule and email / ftp them wherever you want.

Bear in mind that CHDK is a hack. It might work reliably for years. Or it might not. Its up to you to decide the cost of a failure and make the appropriate design decisions.

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Ported : A1200 SD940 G10 Powershot N G16

jcarrr

3

Re: periodic pictures and remote retrieval

« Reply #2 on: 11 / January / 2013, 17:42:30 »

Thank you waterwingz.

I will give it a try. Even if we do not adopt this approach it will be interesting.

In your opinion are there better or worse choices of a camera for this use? If the camera takes pictures on demand or on schedule, it will be a major good deal.

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reyalp

14034

Re: periodic pictures and remote retrieval

« Reply #3 on: 11 / January / 2013, 22:44:15 »

Quote from: jcarrr on 11 / January / 2013, 17:42:30

In your opinion are there better or worse choices of a camera for this use? If the camera takes pictures on demand or on schedule, it will be a major good deal.

It sounds like almost any supported camera should meet your needs. In that case, I'd start with a cheap A series like the A810 or A1200. Since you are talking about using multiple cameras, you could always get higher end ones later if it the system works but you need more capabilities.

A few other comments from your first post:

Quote

It could be powered through the USB connection (as opposed to trying to power the USB system with the 2 AA batteries in the camera).

AFAIK no Canon P&S do this. The current draw is too high for standard USB. Most have a plug for an external power connector, and for those that don't, you can buy or make a fake battery. The Canon branded power supplies are a rip-off.

Quote

The bulk storage card file system was accessible while the camera was in a mode where pictures could be taken and stored.

As waterwingz said, this can be done with the PTP interface http://chdk.wikia.com/wiki/PTP_Extension You might also consider wifi SD cards like http://www.eye.fi/ although if you also need control, PTP is probably a better approach.

Using PTP does require a USB host within USB cable distance of each camera. Something like the raspberry pi that runs a normal linux will allow you to use existing client software.

Quote

Picture taking could be triggered on a schedule, or better, triggered by a remote command.

External control is available either using PTP or a simple electrical control with the USB remote http://chdk.wikia.com/wiki/USB_Shutter_Remote

The latter is mutually exclusive with downloading files over USB.

Quote

Do these cameras have a life time if they are powered up for a couple of years?

Don't think many people have actual data on this, but I wouldn't expect just being powered on to be a problem. Extreme conditions like vibration, dust, large temperature swings, condensation could all be a problem.

Quote

If they get cold and quit working ( know mine does) will they come back to life when it warms up?

If the camera shuts down or crashes, it will not automatically start back up. On some cameras, people have gotten around this by rigging the power button to always be pressed, but I don't know which models this is possible on. I don't know if canon has a cold shutdown threshold, they do specify high and low temp ranges on their specs pages. One common reason cameras shut down in the cold is because the battery output drops, which wouldn't be an issue using an external supply.

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Don't forget what the H stands for.

waterwingz

12138

Re: periodic pictures and remote retrieval

« Reply #4 on: 11 / January / 2013, 23:35:29 »

Quote from: reyalp on 11 / January / 2013, 22:44:15

Quote from: jcarrr on 11 / January / 2013, 17:42:30
In your opinion are there better or worse choices of a camera for this use? If the camera takes pictures on demand or on schedule, it will be a major good deal.
It sounds like almost any supported camera should meet your needs. In that case, I'd start with a cheap A series like the A810 or A1200. Since you are talking about using multiple cameras, you could always get higher end ones later if it the system works but you need more capabilities.

Just what I was thinking - cheap is good. Photo quality for a low cost P&S is probably 90+% of what a premium model gets you for most shots. And from a CHDK perspective, the lowest cost model basically gives you the same functions as the top of the line model. And it cost less to replace when it magically "disappears" into someone's pocket.

However, be warned that CHDK support for any particular new model is not guaranteed and the current models in the store are often not (yet) CHDK supported.

Quote

AFAIK no Canon P&S do this. The current draw is too high for standard USB. Most have a plug for an external power connector, and for those that don't, you can buy or make a fake battery. The Canon branded power supplies are a rip-off.

Sorry- but in this case, buy the genuine Canon brand for your application. The extra $60 per site is nothing compared to your insurance risk from a fire from a Chinese eBay knock-off with no real UL certification.

Quote

The bulk storage card file system was accessible while the camera was in a mode where pictures could be taken and stored.

Really - think about doing this with an external host/remote node like the raspberry pi.

Quote

Do these cameras have a life time if they are powered up for a couple of years?
Quote
Don't think many people have actual data on this, but I wouldn't expect just being powered on to be a problem. Extreme conditions like vibration, dust, large temperature swings, condensation could all be a problem.

Moot point. Same problem with anything you could buy / build.

Quote

Quote
If they get cold and quit working ( know mine does) will they come back to life when it warms up?
If the camera shuts down or crashes, it will not automatically start back up. On some cameras, people have gotten around this by rigging the power button to always be pressed, but I don't know which models this is possible on. I don't know if canon has a cold shutdown threshold, they do specify high and low temp ranges on their specs pages. One common reason cameras shut down in the cold is because the battery output drops, which wouldn't be an issue using an external supply.

If you a building something anyway, being able to cycle the power to the CHDK camera to periodically reset it .. rather than relying it to stay running for months on end ... seems like a wise precaution. So a shutdown from extreme cold would get you restarted once it warms up. And I can only assume that whatever central monitoring s/w you have would alert you to the fact that the "cold soaked" node was offline?

« Last Edit: 11 / January / 2013, 23:43:06 by waterwingz »

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Ported : A1200 SD940 G10 Powershot N G16

reyalp

14034

Re: periodic pictures and remote retrieval

« Reply #5 on: 12 / January / 2013, 01:01:48 »

Quote from: waterwingz on 11 / January / 2013, 23:35:29

Quote
. Extreme conditions like vibration, dust, large temperature swings, condensation could all be a problem.
Moot point. Same problem with anything you could buy / build.

Don't really agree with that. Outside of the D10 and D20, Canon P&S aren't ruggedized at all. It's very likely they are more sensitive to stuff like this than purpose built industrial, security or camera trap systems.

D10 or D20 could be an option, but they are relatively expensive and you have to have the door open for USB and power. You could probably rig something that made a pretty good seal with the plugs in place.

Quote

If you a building something anyway, being able to cycle the power to the CHDK camera to periodically reset it .. rather than relying it to stay running for months on end ... seems like a wise precaution.

This is a very good point. The CHDK cameras are designed to run for a battery pack life (generally a few hundred shots) between reboots. They are not designed to run continuously for weeks on end, and it's likely that things will break down if you try. A daily reboot would be a good idea.

If you use something like the raspberry pi as a controller, you could easily use one of the GPIOs to control power. It would be quite easy to make it attempt to reboot the camera if the USB connection goes away too.

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jcarrr

3

Re: periodic pictures and remote retrieval

« Reply #6 on: 12 / January / 2013, 18:37:47 »

Everyone,

Thank you for the gratifying response. Please gentlemen, feel free to continue the discussion.

Some quick reactions to suggestions and assurance that I am listening.

I purchased a Power Shot A1100 IS for a few dollars on ebay. We will see if it is the supported one. If not, a granddaughter will probably take it off my hands.

We take power supplies quite seriously. Most installations will have enough power available that a heater is easy to implement, some times with just an I/O port, a transistor and a resistor. I read that cameras have some temperature signals available. A bonus! It is important to keep the device and enclosure above condensation temperature. If line power fails, we can warm up the enclosure and camera before powering the camera.

Certainly there will be provision to cycle power. The question really was about the life cycle strategy of keeping it alive continuously verses the component degradation that power cycling might accelerate.

Raspberry Pi is fun. We have a couple of them, but haven't used them except to play.

Thank you for the eye.fi suggestion. It may well solve another, unrelated challenge. Who would have guessed? I wonder how tough they are ....

Even if this approach is not the final solution, I will learn the talk and walk.

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ant_thomas

28

Re: periodic pictures and remote retrieval

« Reply #7 on: 29 / March / 2013, 08:42:12 »

If you are comfortable with a bit of small soldering then the combination of....

Raspberry Pi
Cheap Single Channel Arduino Relay
CHDK Capable camera
Alternative PTP client (http://chdk.setepontos.com/index.php?topic=6231.0)

I have a basic guide here - http://www.antthomas.co.uk/webcam/guide.php of what I did - Camera 2 is the camera in question. I have mine taking photos every 40 seconds which you obviously don't need, but the basics are the same.

The basics are:

You solder two wires to the power switch or view pictures button and attach them to the relay.
Once this is done you can flick the relay on and off to replicate pressing the button.
This turns on the camera.
Using the chdk alternative ptp client you can take a photo, download it from the camera and once that it's downloaded you can do whatever you want with it. In your case upload it via FTP.
Turn the relay on/off again to turn the camera off.

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