mako lightning talk
TRANSCRIPT
![Page 1: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/1.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
Lightning
Atmospheric discharge of electricity.
Often accompanied by thunder.
Travels at 60,000 m/s
30,000 °C (54,000 °F)
![Page 2: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/2.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
Photographing Lightning
A tricky problem:
Hard to predict.
Over pretty quickly.
Cameras can get wet.
![Page 3: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/3.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 4: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/4.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
Approaches using CHDK
Free Software (CHDK) offers two approaches:
The old way: “Wait and hope.”
The new way: Motion detection.
![Page 5: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/5.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
Wait and Hope
Using a CHDK intervalometer script to take long-exposure shots repeatedly.
1-15 second exposures (1-second can work better for lightning) can keep shutter open between 80-95% of the time.
“Dark frame subtraction” addresses noise from long exposures.
Tends to work poorly during the day.
http://chdk.wikia.com/wiki/UBASIC/Scripts:_OMNI_Intervalometer
![Page 6: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/6.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
Motion Detection
A user named “MX3” wrote motion detection functionality for CHDK using variance in luminance.
Triggered by the “lead” strike which immediately precedes every main lightning strike.
Every photograph on camera has a lightning strike.
Works in daylight or even without tripod.
![Page 7: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/7.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 8: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/8.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 9: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/9.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 10: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/10.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 11: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/11.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 12: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/12.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 13: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/13.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010
![Page 14: Mako lightning talk](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a3ce4b1a28ab140d8b46e7/html5/thumbnails/14.jpg)
ben
jamin
mako
hill :: lig
htn
ing
:: deb
con
f 2010