Starting out!

[Brutha]

Hi All,

I've been interested in getting a Raspberry Pi for a while, and now the evenings are drawing in, I think I will go ahead...

I always find it's good to have a project as a way to learn my way round things. I'm thinking that I'd like to make something for taking HDR timelapse sequences.

I'm no expert at programming, but have used various languages in the past, pascal, C, VBA etc, and I'm usually fine jumping into new languages. I'm also no linux expert - but I use OSX and am fairly comfortable with the terminal.

Before I go ahead, here are some thoughts on how I would like it to work:

- It would need to be able to operate off a battery pack of some sort. If I could get a pack that would last around 10 hours, that would be great, but 5 hours would be fine as well I think.

- I'll use the raspberry Pi camera module, rather than control an external camera. I see that I can set EV values with the raspistill command, which is useful for the HDR. One question here though - how quickly does the camera take stills? Can I take e.g. 3 shots with around 1 second between them?

- I don't need the raspberry Pi to do any of the processing of the captured images. I'll do this with various programs on my mac.

- I will be using it outside, in areas far from any sort of internet connection (or even mobile phone connection!). So, I was thinking that in order to control the app I would get a wifi adapter and create an ad-hoc network on the Pi. Then connect to this with the iphone - ideally I'd then use the iphone to see a preview from the camera for framing and set various things e.g. time between shots. Then when i click "go" from the iphone, I'd want the Pi to shutdown the WIFI network (to save battery life) and start recording until I shut it down. Of course, I'm sure I'll need to code this, but would need to do it without coding on the iphone side.

- It will need to be reasonably weather proof, but I'm sure I can figure something out here.

So - if anyone has thoughts on whether the above is achievable that would be great! And also - which model Pi should I get? I've read that the A uses much less power, but I guess it might be limiting if I want to use it for other applications?

Thanks for any thoughts!

[elatllat]

The pi cam might be what you are looking for but it might not as it's got some limitations compared to something 10x the price ( there is an arbitrary eposure limit, and it needs to warm up a bit before getting the whitebalance, it's got a fixed focus and fov, etc)

So you might want 2 or 5 pi+cam to get perfect sync on images used to make the HDR, or if it's night and you don't want grain then use a fat lense and or a DSLR.

[Brutha]

Thanks!

So you might want 2 or 5 pi+cam to get perfect sync on images used to make the HDR

Interesting - are you suggesting just running them in parallel? Or did I misunderstand?

I'm also thinking about getting a cheapo compact camera that works with gphoto2. I'm a bit hesitant to use a dslr, because of the impacts on shutter life of taking lots of pics.

Anyway, more research needed there, as I'm not yet sure what exactly I can control with gphoto.

[d42]

Hi, I work on a similar project. I bought myself a Nikon Coolpix 3300. Gphoto2 supports it and you can power it over USB. I also got a USB hub, WIFI stick and and USB Powerpack. I packed all that into a waterproof plastic kitchen container, drilled a hole a glued some glass over it. You can use silicone or acryl for waterproof sealing.
It looks great, its waterproof but unfortunately it doesn't work as expected
The problem is that the camera doesn't focus correct. Often you get out of focus pictures which destroy the image sequences for the time-lapse. I think I have to get a better quality camera but it is hard to find one which you can power over USB or at least with 5V so that you can use one power source for the pi and the camera.
I am also looking for a web interface to control the camera. At the moment I am doing it over command line but that is not very comfortable.
It would be great if somebody could recommend a good camera and/or webfrontend.

Regards
Torsten