Noob question for a near space project

Status
Not open for further replies.
S

sichroteph

New Member
Hi all,
I want to do a near space project by sending a camera recording at 100.000 feets high.

One of the problem I met is that my camera (which I do not care to lost if problem and take gorgeous videos) only record 15mn of video.

The solution would be to disassemble it and sold an automatic trigger with a pattern like the one I uploaded in attachment.
I do not know where to start and my electronic knowlegde is very rusty...
 
Last edited:
What lifts your camera as high as 100,000 feet? A rocket? A balloon?

It is very very cold up there. Will your camera and its battery work when they are very very cold?
 
I share AG's concerns. Temperature could be way below -60C. If the camera has any moving parts, lubricant on them would be extremely viscous; and battery voltage may drop to to an unacceptable level preventing correct operation of the electronics. You could, I suppose, make an electrically-heated enclosure for the camera.
Do you have some way of tracking the ballon? High-altitude wind could take it miles away from the launch site.
 
thanks for your answer and your worries about the temperature.
The box will be radiation and temperature isolated, with hand warmers and a usb heater plugged into a 18000Mah lithium battery.

It will be by meteorological balloon. My tracking device is android phone bought on Ebay, with an antithieft software. (A sms to the phone make him repond the Gps coordinates)

My camera is a panasonic Lx3, videos taken with it are gorgeous.
Do you think my 15mn video limitation problem can be solved with an automated timer ?
If that work I promise you will be first to see the results
 
Last edited:
It would appear from the manual that the camera, with the appropriate memory card, can be configured to meet your specs without any external control.

At least, that's how I read it.

View attachment 64054

To be sure, you may have to sacrifice resolution for longevity.
 
Last edited:
Having never been inside a camera, I can't even speculate accurately. My assumption would be that the pushbutton is a N.O. pushbutton and wires could likely be soldered in parallel with it for external control. have you opened it? Can you post pics?
 


False hope. It is a cumulated time, at the end of the table it precise that we actually are limited to 2Gb max for a video. (Probably a Fat32 limitation) No burst mode available or custom firmware to help.
@Strantor, I plan to open and post pics it tomorrow. I believe (and hope) that every big button has big welds to be resistant.

Edit : Here is an example of what I try do do:
https://www.youtube.com/watch?v=UAifzh7_-cg
 
Last edited:

Saw that limitation note. Wondered why they listed the additional storage options when they couldn't be accessed.

As for a timer, not a difficult task or circuit (a bistable oscillator driving a monostable w/ output to a simple reed switch to emulate a finger-push). Although reed switch "chatter" might be a problem.

I am curious, however, what your timing scheme represents: is it 12 minutes of recordOFF followed by 2 seconds recordON, then a 2 second recordOFF, then 2 seconds of recordON, etc? Seems odd...

If that's the case, then over a 4 hr period that would only give you only ≈80 seconds of video.
 
Where did the 15min figure come from? (According to the manual, 2GB = 10min 30s of HD quality, 19min of WVGA etc.).
For any timer circuit we would need to know whether the camera 'run' button provides a positive-going or a negative-going signal to the control IC; also the camera operating voltage.
Wondered why they listed the additional storage options when they couldn't be accessed.
Click to expand...
As I read it they can be accessed; it's just that 2GB is the limit for a single continuous run.
 
@cobowbob : I know, they don't say that when you buy it. It is common to all pictures camera.
My plan was to do that pattern with camera on, so it is 12 minutes of record On, 2seconds Off to let the video record into the card etc ...
@alec_t : The 15mn come from what I see on the screen, on my camera with this settings I have a 15mn limitation.

I opened the camera today (always a stressful operation) but I am not happy with the result. The welds are very small, and actually I am not even sure it is welds or just ties.
Mayble you will have an idea seeing the pictures I made. (It is the push button into the circles) It is a multi-layered card so no weld appear on the other side. Do you think I should quit this project and borrow a real camera ?

View attachment 64112
View attachment 64113
View attachment 64114
 
Last edited:
How does the camera button work when recording video? (I looked at the LX3 Manual description, but I'm checking to confirm).

By that, I'm asking the sequence of button pushes to start, stop and then restart the video capture process.

If alec_t is correct (which I think he is), i.e., max 2G file size, but with multiples of that file size allowed as separate, distinct files, up to max the memory card can handle, then maybe a timed, external, solenoid actuated "button pusher" rig might suffice.

BTW, of all the things I've had occasion to disassemble, cameras, IMHO, (especially film - springs, ya know) are often the toughest. Assembly ain't no joy, either. And the PCBs often require a microscope to do any soldering.

Which is why I'm thinking an external solution.
 
Last edited:
strantor said:
View attachment 64124

Wha is the thing I circled in red? Is it a plunger that is depressed by the record button?
Click to expand...

No unfortunately it is the ON/OFF switch :
View attachment 64140

@cowboybob : you and alec_t are perfectly right.
I gave the sequence on my first post, with camera first On. So it would be a 12mn wait while the camera record, followed by a push to stop recordind, 3 secs wait and a push to record a new video etc ...
The mecanical button pusher is a good idea (if it resist to the cold upthere), but I am afraid it is too hard to me to do and it doesnt exist on the market.

Before give up there is an easier solution I didn't thought about in the first place :
- Resetting the camera every 16mn by cutting down the power.
I noticed that when you power on the camera with the button pushed, then the video start recording immediately. Until we reach 15mn, then the camera go to sleep.

- Can we at that moment cut the power for 1 sec with 17 mn cycles ? Seems easier to do, the switch would be on the battery side :

View attachment 64141

In the process the lens goes in and out, not sure it will work in the cold too.
 

If the 'start" button can be continuously be held "on" (somehow taped in place), then that's an excellent solution.

Google "timer Kits", or the like. There's tons out there. Just need one that re-sets itself to zero (after a time interval you can choose) and restarts the count automatically.
 

Great advice, I found that Vellemann made something that probably correspond to my needs:
https://www.apogeekits.com/PDF_Files/datasheet_vm188.pdf

View attachment 64143

If that works and everything goes well I will post here the video just after the lauch, panned for 13 of august, because without you I do not know how I would solve this problem!
Thanks to all of you who tried to help, this community here is completely fantastic.
 
It worked ! The Vm188 worked during the flight, resetting the camera every 16mn and allow me to capture several space video movies.
The youtube link is here :

Video link

View attachment 66516

Thank you all for your precious help, without you I would not have the bottom camera.
 
Last edited:
sichroteph,

WOW!! Great video.

I am mightily impressed!

Quite an accomplishment on a shoe-string budget.

If I may ask, where was your point of launch, where did it land and how did you find it?

I'm guessing that there was a cell phone on board with GPS?

Congratulations. What fun.

CBB
 
hi sichroteph.

Very nice science project.

I was initially concerned about the range of curvature of the Earth shown on your images for 20 miles altitude.
I would not have expected a curvature like that, so I looked back thru your images and I see that the camera lens was introducing the extended curvature.

Dont misunderstand, I am not criticising the project , I think its a great achievement, well done.

E.

The still image looks like its over the Cherburg region.?
 
Last edited:
Status
Not open for further replies.

Similar threads

R
  • Question
Schottky diodes question for circuit
Replies
14
Views
4K
Nigel Goodwin
W
  • Question
PSU choice for Micro project
Replies
5
Views
2K
Pommie
P
S
  • Question
Capacitor question
Replies
16
Views
1K
SentinelAeon
S
  • Question
Project using a Credit Card Payment Terminal as a switch device :))
Replies
15
Views
2K
AnalogKid
A Simple Power Supply Project
Replies
1
Views
2K
Tony Stewart
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…