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projects:timelapsecamera [27/12/2012 00:26] admin [The controller] |
projects:timelapsecamera [31/01/2013 23:05] (versione attuale) admin [First Video] |
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| ==== Hardware ==== | ==== Hardware ==== | ||
| - | * Issue #1: The timer. An atmega8 microcontroller (or any other) would be fine. Must draw the smallest current possible. The lapse-interval is set through six dip-switches with weight 2, 4, 8, 16, 32, 64 seconds. A led is for test purposes, it may be disabled removing a jumper. 8 Mhz quartz is optional, actually the internal oscillator would have been enough. | + | **Issue #1: The timer.** An atmega8 microcontroller (or any other) would be fine. Must draw the smallest current possible. The lapse-interval is set through six dip-switches with weight 2, 4, 8, 16, 32, 64 seconds. A led is for test purposes, it may be disabled removing a jumper. 8 Mhz quartz is optional, actually the internal oscillator would have been enough. |
| - | * Issue #2: Power. I've used a pre-built module that converts 9-12V into 5V through an LM2576 based switching step-down converter, and a 7585-3.3 linear regulator that provides 3.3v. An additional diode provides about 0.6v drop, so the camera is powered at about 2.7v. Other cameras may need different power requirements. | + | |
| {{:projects:timer.png?200|}} | {{:projects:timer.png?200|}} | ||
| {{:projects:img_2158.jpg?200|}} | {{:projects:img_2158.jpg?200|}} | ||
| + | |||
| + | **Issue #2: Power.** I've used a pre-built module (see photo at top of page) that converts 9-12V into 5V through an LM2576 based switching step-down converter, and a 7585-3.3 linear regulator that provides 3.3v. An additional diode provides about 0.6v drop, so the camera is powered at about 2.7v. Other cameras may need different power requirements. | ||
| + | |||
| + | The system is intended to be powered with a 12V lead-acid battery. By theorical analisys, current drawn from the 12V battery should be about 0.5 times the current drawn by the camera. Experimental results are an average camera current of about 440mA, and a battery-drawn current of about 300mA. With this data 7Ah battery (like ups' ones) would last 23 hrs (less than a day). | ||
| + | |||
| + | Possible alternatives: | ||
| + | * 6V battery directly connected to 3v3 regulator (and microcontroller powered by 3v3 instead of 5v). The big drop of 2.7V means lower efficiency and worse performance. | ||
| + | * Other kind of power converter, like a switching 6V (or 12V) directly to the 2.7-3V needed by the camera. Surely better performance, but by now I don't feel like building this. | ||
| + | |||
| ==== Software ==== | ==== Software ==== | ||
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| * The focus signal is first driven low, then after 2 seconds the shutter signal is driven low, another second and both are released to hi-z state. | * The focus signal is first driven low, then after 2 seconds the shutter signal is driven low, another second and both are released to hi-z state. | ||
| * An optional led shows when the photo is being taken (lits up when focusing, turns down a second after the shot). | * An optional led shows when the photo is being taken (lits up when focusing, turns down a second after the shot). | ||
| + | |||
| + | Source can be found here: [[http://www.maetech.it/docs/proj/lapsetimer/main.c]] | ||
| The images below show the working timer. (green trace is focus, active low; yellow trace is shutter, active low) | The images below show the working timer. (green trace is focus, active low; yellow trace is shutter, active low) | ||
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| {{:projects:screen-0001.png?200|}} | {{:projects:screen-0001.png?200|}} | ||
| - | ===== Usage ===== | + | ===== First Setup ===== |
| + | |||
| + | The whole system has been enclosed in a plastic box. There is a hole for the camera lens, protected by a transparent plastic shield, fixed with glue. | ||
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| + | You can see a lead-acid battery in the box, lately it has been detached and put outside the box, and linked with a panel-mount connector. | ||
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| + | {{:projects:img_0806.jpg?200|}} | ||
| + | {{:projects:img_0808.jpg?200|}} | ||
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| + | The first, experimental, usage of this system was capturing the making of the Traditional Bonfire in our town. | ||
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| + | The box and battery have been placed on the roof of an electric power distribution room, 20-30 meters far from the scene. | ||
| - | ===== Converting images to video ===== | + | You should keep in mind the following matters when positioning the camera: |
| + | * You should check with the camera display or in other way how the photo are taken from the point of view you choose | ||
| + | * Imagine where the sun will be at each moment, it could enhance or blind your photos | ||
| + | * Take care of marking down the positioning, or better fix it in a way that it could be detached and placed again in the same position it was before | ||
| + | Make the best adjustments on the camera, automatic would be fine. Decide the size of the photos, we've used 1024x768. Calculate how long the camera will work in standalone, basing on SD card capacity and battery capacity. After that period you have to change battery and/or SD card. | ||
| + | ===== First Video ===== | ||
| + | Over 10 thousands photos have been shooted, of which only 4 hundreds have been used to make the video. A selection and proper ordering is a must. | ||
| + | The video have been made using VirtualDub for Winzoz, other tools can be used (maybe also opensource). | ||
| + | Here it is: | ||
| + | <html> | ||
| + | <iframe width="640" height="480" src="http://www.youtube.com/embed/i5e0a_IXucM" frameborder="0" allowfullscreen></iframe> | ||
| + | </html> | ||
| + | Note this is first version of video, some photos have to be deleted, other have to be inserted. | ||
