Size of video file in Digital Camera

[kaneohe]

I have a simple inexpensive point and shoot Canon digital camera. If I have a 2GB SD
card installed, the camera tells me that there is a potential for
somewhat less than a thousand pictures (say 800) at default settings making the average size about 2MB/photo which roughly agrees w/ what I have read.
I have avoided doing video assuming this would fill the memory in no time at all. Is there a rough general multiplier that applies to estimate the MB/min.
when doing video vs photos? Just looking for some ballpark figure.

[ERD50]

You gotta check the manual. Depending on the format, and what kind of compression they use, it can be all over the map. I have two Casio cameras, similar models, purchased ~ a year apart, and the old one compresses much more, much smaller files, yet looks as good. No rhyme/reason.

Take a video, time it and check the file size. There are usually multiple quality settings, this will affect it a lot. SD cards are ~ $1/GB, maybe a bit more if you need a higher speed one (also in the manual).


-ERD50

[Texas Proud]

Heck, change it to video and it will also tell you how much time you can record... at least all of the ones I have owned has....

[donheff]

I shot a number of short videos (20 sec - 2 min) on my recent trip to Africa and they averaged about 1M/sec. It had it set on the larger video size (640x480?). I kept about 700 photos and two dozen videos and only used one 4G card. One of my traveling companions shot about 2000 photos and dozens of videos and had tons of room to spare on her 16G card.

[kaneohe]

Thanks all for the info. ERD50....the answer may very well be in the manual but it wasn't immediately obvious. TP.....good suggestion. Looks like 20+ min for 2GB so 0.1GB/min or 100MB/min or 1.5MB+/sec which is in the ballpark of donheff's 1 MB/sec. Another way of thinking about it if a still
pic is 2.5MB , then a minute of video equivalent to 40 pics stored (I guess there really are more pics if they are compressed?)

[Texas Proud]

Quote:

Originally Posted by kaneohe Thanks all for the info. ERD50....the answer may very well be in the manual but it wasn't immediately obvious. TP.....good suggestion. Looks like 20+ min for 2GB so 0.1GB/min or 100MB/min or 1.5MB+/sec which is in the ballpark of donheff's 1 MB/sec. Another way of thinking about it if a still pic is 2.5MB , then a minute of video equivalent to 40 pics stored (I guess there really are more pics if they are compressed?)

Actually you can not compare them to a still pic.... still pics are much higher resolution than video...

[Walt34]

Much depends on the resolution. On my Nikon D7000 with a 16 GB card the number of still exposures ranges from 452 shooting RAW to just over 4.2k shooting at the lowest resolution jpg.

Of course that low resolution jpg will make a lousy 8x10 print.

[ERD50]

Quote:

Originally Posted by Texas Proud Actually you can not compare them to a still pic.... still pics are much higher resolution than video...

Not only resolution, but with video, they use one shot as a 'key frame', and then they can follow with several shots with only 'difference' information. As an extreme example, if you take a video of a still scene from a tripod, there is no added info, other than to code the digital equivalent of "the same", until something changes or the system calls for a 'refresh' with another key frame. If a ball rolls across a fixed scene, only the changes along the ball path are recorded in the new frames.

You can see this easily on some high compression videos. Slow moving stuff will look quite detailed (I think they use the extra frames to keep adding detail progressively). But fast moving, or the whole screen moving moderately fast causes a lot of 'pixelation'/blurring.

-ERD50

[BigMoneyJim]

It depends.

I had a camera that stored video in mJPEG format which really is just a series of static JPEGs and not very efficient. It depends on the camera's video hardware encoding format and resolution.