CHDK in the stratosphere

[fbonomi]

[fe50]

WOW - amazing !
This is the 2nd CHDK that worked above ~ 33 km ! (as the HAPS-1 Pegasus HAB Project, A550 - Script both stills and video?).
Since these images are top class, the panorama will be bombastic, i'm sure...WOW !

[Old Farseeing Art]

Outstanding!!!

I took my SD1100 up to a tiny 500 feet (about 1/2% of your mission) today.  I was feeling quite sassy until I saw your photos.   I used a glider and it is not likely to get over 1000 feet.   

Down in Florida, hey?  It would be TRULY outstanding to be up there during a shuttle launch and get photos of that.

I'm looking forward to seeing your script if possible.  Being a newby, I could learn a lot from it. 

Great job!!!

[reyalp]

Awesome pics, great work

[pepeloloz]

Outstanding

[Microfunguy]

Very, very interesting !

Great to see a practical use of sensor temperature and ISO override.

I am almost tempted to add to SDM  

[fudgey]

[yvesson]

[dcshrum]

maybe there's even other things in the rig keeping the camera warm? And it's so much colder that one just can't expect extrapolate linearly that far with confidence.

There is.   If you look here http://dcshrum.ais.fsu.edu/images/IMG_0022.jpg you can see we have a voltage regulator attached to a heat sync.  That was a result of having a 14 volt li-poly battery and a 12 volt motherboard.  The heat sync does get pretty hot.  I never measured it but I'd say after an hour you do not want to touch it.

Curious, has anyone ever wired an external battery?  It would be more efficient to use a voltage regulator off the larger battery.  Actually now that I think about it you could just wire a 5 volt regulator to the USB cable.  But then you would not be able to send signals to the camera.  I believe the camera will run off just USB power. 

[fe50]

[fudgey]

I believe the camera will run off just USB power. 

It's highly likely that it will not work from USB power without exceeding the 500 mA USB spec, not even if you step down to whatever your battery voltage is using a high-efficiency switching regulator. Even if you never use zoom or flash during your flights, you'll have a hard time starting up the camera and shutting it down safely before landing because the lens motors require lots of current.

[fbonomi]

I don't think the camera runs at all from the USB power.

Other cameras (such as the a570) have an external supply jack that could be used. I used it with a wall adaptor or with a motorbike battery for ver long timlapses...

Anyway, we must consider that we are using the USB 5v line as a "data" line to signal to the camera, so we couldn't anyway turn it off without turning off the whole system :-)

[cybercom]

maybe there's even other things in the rig keeping the camera warm? And it's so much colder that one just can't expect extrapolate linearly that far with confidence.

There is.   If you look here http://dcshrum.ais.fsu.edu/images/IMG_0022.jpg you can see we have a voltage regulator attached to a heat sync.  That was a result of having a 14 volt li-poly battery and a 12 volt motherboard.  The heat sync does get pretty hot.  I never measured it but I'd say after an hour you do not want to touch it.

Curious, has anyone ever wired an external battery?  It would be more efficient to use a voltage regulator off the larger battery.  Actually now that I think about it you could just wire a 5 volt regulator to the USB cable.  But then you would not be able to send signals to the camera.  I believe the camera will run off just USB power. 

I used the AC Adapter Kit ACK-DC10 (same for my TX-1s as your SD1100). Cut the cable from the Vdc output side of the adapter, attached connectors and used larger capacity batteries.

Used something like this I found at Radio Shack:

Horizon Hobby: Connector Set 7.2V by Tamiya America, Inc (TAM50106)

By putting matching connectors on the ac adapter as well, I can either use power off the wall or larger battery packs depending on the situation.

And, BTW, Great Pix!!!

HTH,

[fudgey]

[Microfunguy]

I believe the camera will run off just USB power. 

The USB V+ signal is not power, it is a logic signal that turns-on some transistors.
The output from the transistors goes to the DIGIC processor.

The USB signal can be very low power, far lower than some of the USB remote switch circuits pblished.