topic SD Card in EOS DSLR & Mirrorless Cameras

SD Card

chief — Tue, 11 Mar 2014 01:24:25 GMT

Ihave T4i an just purchased a Delkin 32gb 600x memory card, is there a way to tell on my camera lcd how much time I have left in shooting videos. I know it depends on format and such. You can tell how many still photos you have left but how about video.I see on the lcd it shows 29.59, does that tell you how much time for video you are shooting? On the package sd card came in it says about 4 hours so would that mean I can shoot 7 or 8 videos of 29.59 minutes each?

Re: SD Card

Richard — Wed, 12 Mar 2014 20:01:08 GMT

Hi Chief,

When you're recording in Full HD (1920 x 1080) a 32GB card should hold between 94 and 97 minuted of movie recordings (32GB/ 330MB/Min- overhead (File Allocation Table).

The "29.59" is the amount of time you may record unless the 4MB limit is reached before this.

You may find the following table to be useful:

Total Movie Recording Time on Memory Cards and Approx. File Size Per Minute

Movie-recording Size	Total Recording Time (approx.)	File Size (approx.)
Movie's image size	Frame rate (*)	4GBCard	8GB Card	16GBCard
Full HD (Full High-Definition) recording quality [1920x1080]		11 min.	22 min.	44 min.	330 MB/min.


HD (High-Definition) recording quality [1280x720]		11 min.	22 min.	44 min.	330 MB/min.

Standard recording quality [640x480]		46 min.	1 hr. 32 min.	3 hr. 4 min.	82.5 MB/min.

*:Frame rate is the value that indicates the number of frames recorded per second (fps).

[ ] [ ]: For areas where the TV format is NTSC (North America, Japan, Korea, Mexico, etc.).

[ ] [ ]: For areas where the TV format is PAL (Europe, Russia, China, Australia, etc.).

[ ]: Mainly for motion pictures.

NOTE
About Movie Files Exceeding 4 GB
Even if you shoot a movie exceeding 4 GB, you can keep shooting without interruption.
During movie shooting, approx. 30 sec. before the movie reaches the 4 GB file size, the elapsed shooting time displayed in the movie shooting screen will start blinking. If you keep shooting the movie and the file size exceeds 4 GB, a new movie file will be created automatically and the elapsed shooting time or time code will stop blinking.
When you play back the movie, you will have to play each movie file individually. Movie files cannot play back consecutively automatically. After the movie playback ends, select the next movie to be played.
Movie Shooting Time Limit
The maximum recording time of one movie clip is 29 min. 59 sec. If themovie shooting time reaches 29 min. 59 sec., the movie shooting will stop automatically. You can resume movie shooting by pressing the button. (A new movie file is recorded.)

IMPORTANT
When shooting movies, use a large-capacity SD card rated SD Speed Class 6 "
" or higher.
When shooting movies and using a card with a slow write speed, the movieshooting may automatically end or the movie may not be recorded properly. Additionally, when you play back a movie using a card with a slow read speed, the movie may not play back properly.
An increase of the cameras internal temperature may cause movie shooting to stop before the maximum recording time shown in the table above.

Re: SD Card

chief — Thu, 13 Mar 2014 22:27:35 GMT

What do you mean by unless the 4mb is reached. does all this mean I have roughly 3 29 minute long videos?

Re: SD Card

hernhombeecaryb — Fri, 14 Mar 2014 20:27:50 GMT

If I read that correctly it means

The max file size is 4GB
The camera auto creates a new file when needed
You need external editing to spice the video files
Your video may or may not be interrupted when the new file is created
You can not view video files >4GB in camera

Kind of out of order but I think the list cover it.

Re: SD Card

ebiggs1 — Sat, 15 Mar 2014 16:34:13 GMT

Video clips could not be longer than 12 minutes due to the 4GB size limit in the FAT32 file system.

Also there is a over-heating problem. Newer cameras overcome heating problems with redesigned hardware. The 12 minute FAT 32 cap is negated with seamless file spanning. But the 29:59 minute continuous recording cap still stands.

The 29:59 limit has to do with the EU deciding to classify high-end digital cameras as video recorders, which attached a customs duty of 5-12% for cameras imported into Europe. The limit was to offset the classification and avoild the extra tax.

Re: SD Card

TCampbell — Mon, 17 Mar 2014 14:52:40 GMT

The camera uses a "FAT32" type filesystem on the memory card. This provides compatibility with PCs and Macs (and frankly just about every other current operating system) which can read this filesystem.

The downside... is that due to the technical nature of how the filesystem works, no single file may be larger than 4GB. This is not a Canon limit... this is a limit of using the FAT32 filesystem (originally developed by Microsoft).

To get around the limit, the camera would have to use a different filesystem. Windows PCs get around the problem by using the NTFS filesystem. Macs get around the problem by using the HFS+ filesystem. There are lots of filesystems that do not have this limitation. But these solve one problem while creating other problems. NTFS is Microsoft proprietary. If anyone else wants to use the NTFS filesystem, they have to pay licensing royalties to Microsoft. Similarly, if anyone else wants to use HFS+ they would have to pay licensing roytalties to Apple. This means that if Canon chose one of those filesystems, a large percentage of their customers would have a compatibility issue. There are open-source filesystems that get around the problem, but these are not standard on either PCs or Macs and would require that consumers understand how to download and install them -- making the products complicated to use for the average consumer.

As such, they stick with the FAT32 filesystem and it's 4GB limit.

The limit isn't really a problem in professional video. In professional video, they shoot lots of short clips (and cut them into even shorter clips). They do not do the "one long continuous scene" type shooting that home users tend to do. Watch any movie, TV show, or even a TV commercial. When you see a scene cut to a new camera angle begin counting out seconds to yourself... you may be surprised at how difficitult it is to count to 10 before they switch camera angles again. The "one long continuous shot" is not very interesting.

As for the 30 minute limit (29 minuts and 59 seconds).... this is a trade agreement problem. The World Trade Organization "Information Technology Agreement" (ITA) apparently sets an agreement that if a camera cannot record video longer than than 30 minutes then it does not have to be classified as a "video" camera. This is important only because of how cameras are classified and tariffed for purposes of trade. If a camera is classified as a video camera, then there are trariffs applied which are not applied to regular cameras. In other words, the cost of all cameras that can record video for 30 minutes or longer would have to go up.

So this is an example of a situation where there is no technical problem... it's a political problem. But it's a political problem beyond the control of Canon (or any other company that produces cameras).

If recording video continuously for at least 30 minutes is a true necessity, you would need to use a true "video" camera rather than a DSLR. Incidentally, those cameras still have the 4GB file size limit too... but they solve it by storing long videos into chunks... at the end of a 4GB section of file, they automatically start a new file. This might get you to wonder why they don't just do the same thing for DSLRs. That's probably because if the DSLR has a way to skirt the 30 minute limit then they'd be forced to pay the tariff.

One last thing to keep in mind... a 1080HD video camera has a sensor which is only about 2 megapixels (1920 x 1080). A regular DSLR has a sensor which has vastly higher resolution. There are heat issues for DSLRs that video cameras don't have. If you REALLY need long clips, you probably want a video camera anyway.