file size for HD video

what approx file size would you expect on a HD video of 30 mins on an EOS 550

It depends which mode you shoot in. The owner's manual gives a rough estimation of file size in 'megabytes per minute': Multiply the Mb/Min X 30 and you should have a close estimation.

640X480 = 165 Mb/Min ---- 1280X720 = 330 Mb/Min ---- 1920X1080 = 330 Mb/Min

Note that the memory card uses FAT32 format and as a result, the maximium size allowed for a single file is 4 Gigabytes. When the 4 Gig limit is reached the camera will stop recording. This means you can't record continuously for 30 minutes in any of the video modes. You'll get about 24 continuous minutes at 640X480, but only about 12 minutes continuous shooting at 1920X1080.

Jim_T wrote in post #11369593
It depends which mode you shoot in. The owner's manual gives a rough estimation of file size in 'megabytes per minute': Multiply the MB/Min X 30 and you should have a close estimation.

640X480 = 165 MB/Min ---- 1280X720 = 330 MB/Min ---- 1920X1080 = 330 MB/Min

Note that the memory card uses FAT32 format and as a result, the maximium size allowed for a single file is 4 Gigabytes. When the 4 Gig limit is reached the camera will stop recording. This means you can't record continuously for 30 minutes in any of the video modes. You'll get about 24 continuous minutes at 640X480, but only about 12 minutes continuous shooting at 1920X1080.

Fixed the units for you. "MB" = megabytes; "Mb"= megabits.

The calculation is good, but it is approximate, since the size is also dependent on the effectiveness of the data compression, which is impacted by the subject of your video, including how much things are moving.

davem01 wrote in post #11368997
(W)hat approx(imate) file size would you expect (from) a(n) HD video of 30 min(ute)s (using) an EOS 550(D?)

After actually using a 550D/T2i to record video at 1920x1080 resolution and 30fps: expect a 30-minute video recording at that resolution and frame rate to fill around 12 gigabytes.

RTPVid wrote in post #11369801
Fixed the units for you. "MB" = megabytes; "Mb"= megabits.

Actually, in the Canon T2i/550D owner's manual on page 132, Canon shows it as MB/min so guess I should have said Megabytes per Minute .... And yes, the subject and compression rate can vary things a bit.

DC Fan wrote in post #11370713
After actually using a 550D/T2i to record video at 1920x1080 resolution and 30fps: expect a 30-minute video recording at that resolution and frame rate to fill around 12 gigabytes.

Are you getting single files that are 12 Gig in size on your memory card?

Jim_T wrote in post #11371429
Are you getting single files that are 12 Gig in size on your memory card?

Not yet. But when you get a 3.8 GB file from recording 11 minutes and 30 seconds of 1920x1080 / 30fps video, it's safe to assume that three times the length will generate three times the file size.

DC Fan wrote in post #11371756
Not yet. But when you get a 3.8 GB file from recording 11 minutes and 30 seconds of 1920x1080 / 30fps video, it's safe to assume that three times the length will generate three times the file size.

Actually, it will result in 3 separate files, assuming you restart after each file, since Canon DSLRs stop recording at ~4GB. (Caveat: I haven't tested this personally; it comes from what I've read.)