# Video capturing stops without reason



## mukul (Aug 16, 2014)

Hi all,
I have 600D and in my few tries I noticed video recording stops abruptly.

Last time I tried to see what's is happening
First one stopped at 36sec
Second one at 6 sec
Third one at 2min, 16sec
Camera was on tripod, using manual focus lens (m42) 

I'm using 16 GB Sandisk ultra 30MB/s class10 SD card.

Can you please tell me what is happening.

Thanks all


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## sjschall (Aug 17, 2014)

_Technically_ your card should work as it is class 10, but _realistically_ the 30Mb/s is a little slow and could be the issue. You may want to try some faster cards and see if the issue persists.

Do you see the little buffer icon on the LCD before it stops? It looks kind of like a battery indicator with 2 or 3 bars that flashes if the card buffer is filling up to quickly.


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## Mt Spokane Photography (Aug 17, 2014)

Class 10 cards write at 10MB/sec, so don't be fooled by the 30MB/sec baloney. There is a technical reason, but I'll not repeat it.

Where did you buy your card? A user in a similar situation returned his card and found it was counterfeit. That card was purchased from Amazon.

I have sold items on Amazon, and after spending lots of time reading the fine print, I discovered that some inventory is often being co-mingled, assuming it has the same bar code. It all goes into a big bin, each seller gets credit for the quantity he ships to Amazon. This means that you can get fake cards from Amazon, no matter who the seller is, even if its Amazon. I buy straight from a camera store, or on Amazon from someone like Adorama who ships the product from their warehouse. 

Amazon needs to find a solution. Many makers of high end items are already putting the brakes on Amazon sales.

http://online.wsj.com/articles/on-amazon-pooled-merchandise-opens-door-to-knockoffs-1399852852


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## Lightmaster (Aug 17, 2014)

> Technically your card should work as it is class 10, but realistically the 30Mb/s is a little slow and could be the issue. You may want to try some faster cards and see if the issue persists.




*WRITE* speed of class 10 cards is 10 mb/s.

that´s a mimimum rate the card has to fulfill for class 10 rating, but often SD cards deliver not much more.

i have a few sandisk 32 GB class 10 cards and have tested them with different benchmark programs. 
the max performance was around 12 mb/s.

i guess what sandisk prints on the cards as mb/s is not the write speed but the read speed.
at least that way the numbers come closer to reality.


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## Maui5150 (Aug 17, 2014)

Best two suggestions for you... 

Test it and watch it... Then get or borrow a faster card and see if it happens.

Slow cards are not noticeable in when you are shooting pictures generally unless you are doing a long burst. Video??? As you have found, can be noticeable in the first minute


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## Mt Spokane Photography (Aug 17, 2014)

First, do a low level format on your card. This erases the card and returns it to new condition, and it will write at full rated speed. That may fix the issue. If it doesn't, then do a low level format on a borrowed card before testing it.

All testing on SD cards should be done on cards that have first been low level formatted. The reason is that once a card has been used, a regular in-camera format does not erase the card, so the camera first erases a sector on the card in order to write to it. This is relatively slow and gives misleading test results. Card speeds are all based on a low level formatted card. 

The slower speeds should not be a issue for good quality cards. However, a counterfeit will often fail to erase / write fast enough because of the junk quality memory inside.


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## Lightmaster (Aug 17, 2014)

and you better use this tool instead of the OS tools:

https://www.sdcard.org/downloads/formatter_4/

i always wondered why low level format is so quick on SD cards.
there is an ERASE command that can erase many block simultaneously (ERASE_WR_BLK_START (CMD32), ERASE_WR_BLK_END (CMD33) commands).

the data at the card after an erase operation is either '0' or '1', depends on the card vendor.


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## mukul (Aug 18, 2014)

I was using 1920x1080 @25 FPS

@sjschall : yes "little buffer icon on the LCD.. like a battery indicator"


ok this is card problem... 
I tested another 4 GB Sandisk ultra 30MB/s class10 SD card. This card was supplied by canon with the camera. It recorded cool 08:25 mins of video till card was full and never showed the buffer icon.

After that I formatted the 16GB card with is program https://www.sdcard.org/downloads/formatter_4/ @Lightmaster and tried it. It stopped after ~2 and half mins and showed the buffer icon quite a few times.


Thinking what to do? 
Should I contact Sandisk directly with the issue?

thanks all for your time


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