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#345747 - 15/06/2011 20:40 Weird idea
Dignan
carpal tunnel

Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
I'd love to hear what ideas you guys have for something pretty odd and specific that I'd like to try.

I'll give you the background: Last July 4th, we walked to the closest community fireworks show around us to see the display. It was insanely hot, we had to walk about two miles (in 95 degree heat with around 90% humidity), and the sightlines were terrible. The crowds basically had to stand under the tree-line to get far enough away from the launch site.

We live in a condo complex with an above-ground 6-story garage. Looking at Google Maps, it appears there's a direct line of sight from the top story of that garage to the same fireworks display, but it's at a different angle than the viewers at the park get.

Question #1: I've never thought about it before, but am I correct in assuming fireworks are mostly three dimensional? I assume some are not (like the ones that make shapes), but can most of them be seen from any angle and look the same? I won't be surprised if I'm completely wrong about this...

This year, my wife and I have already been invited to a 4th of July party, and I don't think I'd be able to convince her next year to hang out on the parking garage on the chance that we might have a good view of the fireworks.

So that leads me to a little project I was thinking of trying. I'd like to try to capture images of what the display looks like from that angle.

This lead me to thinking about the hardware I'd need for such a project. The easiest thing I can think of would be to get an old canon point and shoot and put that alternative firmware on it. I believe that would give it the ability to do timelapse, but I don't know how the battery would work for such a thing.

I see two challenges to this idea. The first is that I want it to be discrete. I don't want someone taking the capture device or moving it.
The second is, as I mentioned, battery life. We'll probably be gone for the entire afternoon, so it would have to last for up to a maximum of around 8 hours.

I'd love to hear what you guys can think up for such a thing.


ps- of course, in the end, I'll probably scrap all my plans, and leave a note under a rock asking any other possible people with the same idea to take a photo and email it to me smile
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Matt

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#345749 - 15/06/2011 22:02 Re: Weird idea [Re: Dignan]
pca
old hand

Registered: 20/07/1999
Posts: 1102
Loc: UK
You can certainly use CHDK for this sort of thing, it can have scripts set up for timelapse very readily. It works with most Canon camera that have a Digic 2,3 or 4 chipset, which is pretty any of them that use SD cards and aren't DSLRs.

You would need a reasonably modern one, that took SDHC cards, otherwise it would have a limitation of 2GB, which might be a problem.

Power shouldn't be too much of an issue. They all use a single cell lithium-ion battery, which is nominally 3.7v. They're generally rated at 4.2 to 4.3v. Assuming you don't have any mains electricity in the area you want to use the camera, the easiest method is probably something like a small 6-12V SLA battery, around the 7Ah range is very common, running a 4V switch mode power supply.

The quickest and simplest way of doing this with off the shelf parts that I can think of is:

1 x 12V 7Ah lead acid gel cell such as this (it's overpriced, find a cheaper one!)

1-4 diodes such as these

1 x RC model S-BEC such as this (this will give you 5V with 90%+ efficiency)

Wire the SBEC to the 12V battery, and you have a nice little portable 5V power supply. Use the diodes in series with the 5V line to drop enough voltage to get you into the 4.2V range the camera requires. In theory one will do it, but as the voltage drop of diodes goes down as the current goes up, you might need two in series. Use something like a 6V flashlight bulb as a load to draw about 1 amp, and make sure it doesn't go over 4.3v like this. The camera will work down to about 3V or so, it will just give low battery warnings.

You wire the power supply to the battery terminals in the camera, and run the wires through the little covered hole in the battery compartment hatch that almost all of them have, even though they never produced a battery eliminator that fits the damn things!. Put a switch and fuse, around 1.5A, in line as well.

The whole gubbins can be packed into quite a small discrete box that no-one will notice, and given a sufficiently large memory card will snap pictures for days with no problems.

You could obviously use different batteries, or power supplies, but this is all off the shelf bits that shouldn't cost more than perhaps $40. Plus the camera of course.

pca
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#345750 - 15/06/2011 22:11 Re: Weird idea [Re: pca]
larry818
old hand

Registered: 01/10/2002
Posts: 1039
Loc: Fullerton, Calif.
I think I would use a vid cam with a voice activated feature. I'm thinking that the booms from the fireworks would startup the vid camera and keep it going for the whole show.

Of course, you'd need a lot of power (why not just park the car up there and use it's battery? put the camera inside.) and you would probably have to build the noise activation feature...

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#345752 - 15/06/2011 23:15 Re: Weird idea [Re: Dignan]
tanstaafl.
carpal tunnel

Registered: 08/07/1999
Posts: 5549
Loc: Ajijic, Mexico
Originally Posted By: Dignan
I'd like to try to capture images of what the display looks like from that angle.
Having some experience photographing fireworks, I can tell you that shooting from your garage is feasible, but there are pitfalls.

How are you going to set up your exposure and your focus in advance? I have found that f2.8 @ 1/30 second works for me, with an ISO setting of 800, but YMMV.

The idea of time exposures is heading in the right direction, but I think you are underestimating the transience of fireworks explosions. You have about a 1/4 second window in which to catch the fireworks burst at or near optimum radiance. I found that I could not do this even when I was there operating the camera because between my reflex time and the shutter delay I was always too late. The chance of catching the proper moment with an unattended automaton taking the pictures is slim.

I finally (well, relatively quickly, actually) decided to give up on trying to "take pictures", and just zoomed out to a wide enough angle to catch the show, put the camera on continuous shooting (it ran at about one frame every second) and pointed it up into the sky, not even bothering to look through the viewfinder. This worked fairly well, out of 300+ exposures about 100 had something worth keeping.

However, if you're talking about eight hours of this, you better have a pretty big memory card because you will need about 28,000 exposures. That'll take about 120 GB at any decently high resolution. I guess if you can build in a timer to start everything up at the hour the show is scheduled to start...

tanstaafl.


Attachments
Firework.jpg


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#345753 - 16/06/2011 01:18 Re: Weird idea [Re: tanstaafl.]
Dignan
carpal tunnel

Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
I have a big day tomorrow so I have to get to bed very shortly, but some quick responses:

Patrick - thanks so much, I might actually attempt this one. I've never done anything like it, though, so I'm concerned about my abilities. Oh, and I'm also pissed that they never made something for consumers that utilized that hole in the bottom of almost every single Canon POS. You see them plugged in at the store that way!

Larry - unfortunately there really isn't any way to get power to the location. I'd need to rig something like Patrick is talking about, and a vid cam would take too much juice.

Doug - sorry if I wasn't clear, but I in no way care about the quality of the photos. I'm just going to be setting it to take a photo every 30 to 90 seconds at the lowest quality and hope that it grabs the general shape of the display. I'm simply looking to see what's visible from that location.
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#345754 - 16/06/2011 04:14 Re: Weird idea [Re: Dignan]
StigOE
addict

Registered: 27/10/2002
Posts: 568
If you use CHDK, you might be able to use a motion capture script instead of timelapse. They have been used for taking pictures of lightning, so should be fast enough.

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#345758 - 16/06/2011 10:05 Re: Weird idea [Re: StigOE]
pca
old hand

Registered: 20/07/1999
Posts: 1102
Loc: UK
Ah, yes, I forgot you could do that! It would probably work quite well.

pca
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#345763 - 16/06/2011 13:12 Re: Weird idea [Re: pca]
tman
carpal tunnel

Registered: 24/12/2001
Posts: 5528
Originally Posted By: pca
You wire the power supply to the battery terminals in the camera, and run the wires through the little covered hole in the battery compartment hatch that almost all of them have, even though they never produced a battery eliminator that fits the damn things!. Put a switch and fuse, around 1.5A, in line as well.

Eh? They've made AC adapters for the IXUS/PowerShot range. You get a little dummy battery with a socket on the bottom and a brick on a leash PSU that plugs into it via the hole in the camera. I used to have one for my old IXUS but I've since upgraded and they changed the battery shape slightly.

Like this AC adapter suitable for NB-6L batteries. It is pretty expensive though and you need to get the right one for your type of battery.

Third party adapters also exist.


Edited by tman (16/06/2011 13:14)

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#345764 - 16/06/2011 13:47 Re: Weird idea [Re: tman]
pca
old hand

Registered: 20/07/1999
Posts: 1102
Loc: UK
I spent ages looking for one those things some years back, and while they existed in the part reference on Canon's website, no dealer or distributor would admit to ever even having seen one, never mind stocking it.

I guess the sitution has changed. Funny, as the most recent Canon camera I got (an S90) no longer has the facilities to use such an adaptor smile

Well, as they are apparently available, the problem originally stated could be solved either with one of these plugged into the mains, or via the adapter to the PSU I previously mentioned.

pca
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Experience is what you get just after it would have helped...

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#345765 - 16/06/2011 13:49 Re: Weird idea [Re: tman]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
The core problem you face isn't powering the camera, it's dealing with the assorted drunkards who will also be taking advantage of the very same garage for the view it offers.

My suggestion is that you park your car up there and mount your camera inside the windshield, near the top but below any tinting that might be there. A wide variety of such gadgets are available (here's a cheap one from Amazon). Be sure to clean your windshield inside and out.

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#345772 - 16/06/2011 16:33 Re: Weird idea [Re: pca]
tman
carpal tunnel

Registered: 24/12/2001
Posts: 5528
Originally Posted By: pca
I spent ages looking for one those things some years back, and while they existed in the part reference on Canon's website, no dealer or distributor would admit to ever even having seen one, never mind stocking it.

Ahh. Yeah. It wasn't easy to buy the one for my old IXUS at all. I ended up finding it in a photography shop in the US whilst I was on holiday a few years back. I had the same problem as you when I looked for it in the UK as nobody knew what it even was and they wouldn't/couldn't special order it.

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#345811 - 17/06/2011 18:55 Re: Weird idea [Re: Dignan]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31600
Loc: Seattle, WA
Quote:
Question #1: I've never thought about it before, but am I correct in assuming fireworks are mostly three dimensional?


You just gave me an awesome idea. Don't know how it can be done, but man now I really want to do it.
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#345824 - 18/06/2011 02:30 Re: Weird idea [Re: tfabris]
Dignan
carpal tunnel

Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
Originally Posted By: tfabris
Quote:
Question #1: I've never thought about it before, but am I correct in assuming fireworks are mostly three dimensional?

You just gave me an awesome idea. Don't know how it can be done, but man now I really want to do it.

I don't know what you're thinking, but now I'm thinking Matrix-style bullet-time camera rig...


Edited by Dignan (18/06/2011 02:30)
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Matt

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#349703 - 06/01/2012 18:08 Re: Weird idea [Re: Dignan]
Dignan
carpal tunnel

Registered: 08/03/2000
Posts: 12341
Loc: Sterling, VA
Revisiting this thread (sorry), I'd like to try this again with a different camera. My wife's Christmas present was a fancy new Canon S100 (it's freaking awesome for a point and shoot), and so I'd like to do something with her nearly 5 year old SD1000. It has the little flap on the bottom that you'd use for an AC adapter, so now I could use something like this to power the camera. However, I'd like to be able to power it for a long time without an outlet available. Does anyone know of a battery I could use for this kind of purpose? I'm looking for a pre-built solution, as I don't have the know-how to wire this kind of thing myself and make it look prettier.

*edit*
I think an ideal solution would be if I could find something like this, but with the right plug for the little phony battery you put inside the camera. Then I'd have a way to connect the camera to an AC outlet when I wanted, and have a little portable battery pack when I needed it placed somewhere where that isn't possible.

Heck, that would be kind of nice for just carrying around. Those tiny little Canon batteries have pretty bad capacities...


Edited by Dignan (06/01/2012 18:14)
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Matt

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