Author Topic: 64megs = how much Raw Video ?  (Read 11436 times)

Promist

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64megs = how much Raw Video ?
« on: April 03, 2014, 03:11:16 AM »
hi,

I've seen info online which suggests that RAW video takes around 85mb/s.
According to this and an online calculator, that equates to around 306 megabytes per hour.

So, does a 64meg card hold around 10 minutes of RAW footage in practical use ?


ted ramasola

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Re: 64megs = how much Raw Video ?
« Reply #1 on: April 03, 2014, 05:06:23 AM »
So, does a 64meg card hold around 10 minutes of RAW footage in practical use ?
If you will get a 64 "megabyte" card it will hold about about less than a second. ;)

The more useful ones are 64gigs which would hold about 15 min depending on your frame rate and resolution.
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Promist

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Re: 64megs = how much Raw Video ?
« Reply #2 on: April 03, 2014, 03:01:32 PM »
Hi.  Sorry for the mis-type... I wasn't sure if it was megaBYTES or megaBITS per second. 

Yes, I was referring-to a 64GB card.   :)


Thanks for the info.

mageye

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Re: 64megs = how much Raw Video ?
« Reply #3 on: April 03, 2014, 03:49:20 PM »
You will get even less on a 64Mb (megabit) card (by a factor of 8 ) (if one existed that is!) :D
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Promist

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Re: 64megs = how much Raw Video ?
« Reply #4 on: April 04, 2014, 03:26:43 AM »
Ha :)

Please remind me not to post anymore when I'm fighting off a cold   : ???

moswanted

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Re: 64megs = how much Raw Video ?
« Reply #5 on: April 24, 2014, 04:39:56 PM »
Depending on resolution and frame rate 64GB usually result in something between 8-25minutes of raw footage.

Ramon

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Re: 64megs = how much Raw Video ?
« Reply #6 on: April 26, 2014, 11:41:46 AM »
It's not completely accurate, but around 1.7 Bytes are used per pixel, per frame.
So if you would have recorded 1920 x 1080 at 24 fps, you would have 1920*1080= 2 073 600 pixels in a frame. That means a file size of about 2 073 600*1.7= 3 525 120 bytes per frame, which is around 3.5 Mega Bytes (MB). (more like 3.4.. but I'll leave it to 3.5)

So your file size per second will be 3.5*24≈ 84.6 MB
When you calculate this the other way around, for example.. how many seconds will fit into 1 GB? It will be around 1000/84.6≈ 11.8 seconds per GB.

So a 64GB card.. which results in something like 59 GB of usable space, will store about 59*11.8≈ 696 seconds.. Which is about 726/60≈ 11-12 minutes of 1920 x 1080 24p raw

This way you can calculate it for any resolution and frame rate ^^
For example 1344 x 562 in 24 fps will be:

1 000 000 000 / (1344 * 562 * 1.7 * 24)≈ 32.4 seconds per GB
(1GB in Bytes)--(width)-(hight)-(1.7)-(fps)

So a 64 GB card will hold about 59  *  32.4/60≈ 32 minutes of 1344 x 562 24p raw

As you can see, file size will depend a lot on your resolution. But if your card can't even write as fast as 90 MB/s.. you won't be able to record at 1920 x 1080 24p at all.. not to mention a stable continuous recording ^^

Hope this helped in some way, haha

poromaa

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Re: 64megs = how much Raw Video ?
« Reply #7 on: April 26, 2014, 02:20:06 PM »
Another way to get an estimate is to look in the ML-menu. While browsing resolutions you can see how many MB/s and even a frame/time approximation [this however seem to be non-working at latest build??] :). This works only after you have recorded something as the estimate is based on previous recording speed.

Would be nice to see time instead of frames IMO (or both).