Crib sheet: Time-lapse calculation

While on a day long time-lapse shoot today, I wondered about how long my various cameras' card space would last and how much video I'd end up with. I had various memory card sizes. In the past I'd just work it out on the fly but today I thought a quick crib sheet would be useful.

Calculating video length

(assuming playback is 25fps, as it always is here in Europe)

• 30 seconds interval = 5 seconds of video per hour of shooting
• 10 sec interval = 14 seconds of video/hr shooting
• 5 sec interval = 29 seconds of video/hr shooting
• 1 sec interval = 144 seconds (2min 24secs) of video/hr shooting

How long before the memory card is full?

(assuming 1.7Mb per picture and actual card capacity is ~90% of nominal capacity)
(1.7Mb is the average file size of 'Medium Normal' quality on the Canon 600D, YMMV etc)

• 30 seconds interval: 4Gb card in 17 hours, 8Gb card in 35 hours, 16Gb in 70 hours
• 10 sec interval: 4Gb in 5.8 hrs, 8Gb in 11.6 hrs, 16Gb in 23.2 hrs
• 5 sec interval: 4Gb in 2.9 hrs, 8Gb in 5.8 hrs, 16Gb in 11.6 hrs
• 1 sec interval: 4Gb in 35 minutes, 8Gb in 70 mins, 16Gb in 141 mins (2hrs 20mins)

How long before the battery is flat?

Canon (or your camera manufacturer) will have their own claims about the number of shots the camera will make on a single battery. The typical battery capacity in my various Canon SLRs is 1200mAh.
In recent months I've been experimenting with battery technology, and I have a custom-modified battery pack which has a capacity of 6500mAh, and in my tests will last for 3700 shots. I also have a 9800mAh pack which I will test soon.