My T2i stops recording after a few seconds a lot all of a sudden! Very frustrating.

skital

Well-known member
I'm using a class 10 Transcend card which has been pretty good to me so far. I have magic lantern btw, but I went back to the original bitrate. Even before at -7 Qscale it wasn't stopping the recording nearly as quickly or often as it is now at the default Canon bitrate. I'm lucky if i get 10 seconds and it's quite frustrating. What is going on here? I do get the buffer bars a lot, btw.

Thanks!
 
I would recommend upgrading your ML version and making sure to reformat in Camera. Based on your description it seems likely those are the issues.
 
Agreed- IMO, the bottleneck in image quality is not the bitrate. Its in the codec and sensor resolution, which qscale values won't fix.

That being said, fragmented cards are the most common reason for this to happen. Have you been deleting items to clear the card, or reformatting?

My practice is to NEVER DELETE ANYTHING OFF THE CARD. Don't like a take? Just keep going. You'll delete it all when you reformat later. Deleting items individually leaves the memory addresses fragmented on the card, which will slow down even the fastest write speeds (as the camera needs to go hunting around aggregating memory addresses on the card to continue shooting- this causes the buffer cache to fill up too quickly and stop recording).

Since adopting this practice, my 550D only stops recording when it reaches the 4GB file limit (12-15 min).
 
Like they said... h264 isn't anything like AVCHD bitrate, and especially not on these very low res, line-skipping video outputs you get on the first-gen Canon DSLR's. Personally I've just had trouble with ML.
 
Agreed- IMO, the bottleneck in image quality is not the bitrate. Its in the codec and sensor resolution, which qscale values won't fix.

That being said, fragmented cards are the most common reason for this to happen. Have you been deleting items to clear the card, or reformatting?

My practice is to NEVER DELETE ANYTHING OFF THE CARD. Don't like a take? Just keep going. You'll delete it all when you reformat later. Deleting items individually leaves the memory addresses fragmented on the card, which will slow down even the fastest write speeds (as the camera needs to go hunting around aggregating memory addresses on the card to continue shooting- this causes the buffer cache to fill up too quickly and stop recording).

Since adopting this practice, my 550D only stops recording when it reaches the 4GB file limit (12-15 min).

Yeah, I delete stuff off of the card that I don't want regularly, but it never has hurt my shooting time performance before like this. Guess I need to reformat and see what happens.
 
Like they said... h264 isn't anything like AVCHD bitrate, and especially not on these very low res, line-skipping video outputs you get on the first-gen Canon DSLR's. Personally I've just had trouble with ML.

What kind of trouble did you have? And yeah, I hope Canon fixes these issues with the T4i.
 
Yeah, I delete stuff off of the card that I don't want regularly, but it never has hurt my shooting time performance before like this. Guess I need to reformat and see what happens.

Yeah, stop doing that. I can almost guarantee the problem will go away. Its a textbook example and nothing at all to do with ML.
 
I have the newest version of ML with HDR video.

That is why I said based on your description. As far as I can tell from my versions they stopped using Qscale as a term awhile ago. That is why I thought you might have an older one.
 
Yeah, stop doing that. I can almost guarantee the problem will go away. Its a textbook example and nothing at all to do with ML.

Ok, thanks. I had no clue that affected peformance whatsoever. I've always done it before ML and never had an issue nearly this bad. Guess I need to upgrade to a bigger card then. This 8GB is not cutting it.
 
That is why I said based on your description. As far as I can tell from my versions they stopped using Qscale as a term awhile ago. That is why I thought you might have an older one.

Ah. Ok. I just tested out Qscale because their CBR thing stopped recording almost immediately. Qscale seem to do ok for me at around -7, but now it's worse even with the Canon default without Qscale.
 
set CBR at 0.9, especially if you are shooting with lots of motion or at 50P/60P or variable framerates in HDR mode. neither my Sandisk 8GB class 10's nor Kingston 16GB class 10 seem to like what i was shooting (lots of motion, sun coming through window blinds or between wooden slats at 720P 60 at 3 or greater EV difference, and CBR 1.0) but with CBR at 0.9 i had no further problems.
 
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