On examining the files on the card after continuous recording each file is 3.9 gb in size. So i assume the 4 gb limit was reached before the 12 minute limit in every case.
I was pointing camera at a tv screen.

Gotcha, thanks for that information

They are one and the same thing. 4gb = 12 minutes because codec is set up to do CBR so it's predictable what length you'll get..

Setting the qscale in magic lantern to a lower value lets you record much longer - over half an hour if you don't mind the quality loss. You can choose a good trade off that suits you between clip length and quality. Qscale means going over to VBR, so it is not possible to determine the maximum clip length for a given setting, because it depends on the complexity of the images being recorded.

It seems Canon were not expecting Magic Lantern to achieve this ability, because while the 29 minute limit does exist in 640x480 mode (tax reasons), it has not been applied in 1080 mode :)

Thanks for that James.
Could you tell me James what qscale value equates approx. to the default CBR bitrate from Canon?

So is the continious recording feature in the latest stable version of Magic Lantern?

This almost sounds too good to be true

I was just about to buy a small camcorder to leave up the back, but with ML I can just use my 550d?

too good to be true?

It is not totally continous recording, there is a gap of about 1.5 seconds before the next clip starts recording. I tested this with a digital stopwatch, so beware if you are syncing 2 cameras. Its to long a gap to use for anything like a wedding ceremony, but still very handy for a lot of uses. The 29 min 59 second limit does apply to 1080 clips. I have tried all the lower minus settings and every clip is exactly 29 mins 59 seconds long. Simply go to the last frame of the clip to get the length of it.

-1: 8.8 Mb/s
-2: 9.6 Mb/s
-3: 11.8 Mb/s
-4: 13.9 Mb/s
-5: 15.0 Mb/s
-6: 17.1 Mb/s
-7: 21.0 Mb/s
-8: 24.3 Mb/s
-9: 29.6 Mb/s
-10: 35.3 Mb/s
-11: 42.0 Mb/s
-12: 48.0 Mb/s
-13: 56.3 Mb/s
-14: 64.2 Mb/s (flashes overheating icon and stops recording after 2 seconds)
-15: 67.5 Mb/s (flashes overheating icon and stops recording after 2 seconds)
-16: 86.7 Mb/s (flashes overheating icon and stops recording after 2 seconds)


Hope this helps

thats great to know, i would use the 550d ad a c-cam up the back of the church, getting a wide, so I can deal with the 2 sec gap between 12min / 4gig clips.,

Now to install ML on my 550d,

is the continious rec feature in the latest stable version? I dont see it mentioned on th page

550D - Magic Lantern Firmware Wiki


?

Russ, sorry I missed your query earlier.

False colors is another way of judging proper exposure. Advanced monitors and cameras have this feature. I first ran into on my Marshall monitor, and found it resolve a lot problems with trying to guess how the image was going to be exposed. Essentially it converts the image into zones of lighting that tell you what a particular part of the image is being exposed at in IRE.

The zones break down as shown on the attached chart. I understand that you want your lighter faces to come in around 55 to 60. You want to keep your images out the red because of clipping, and also out of fushcia to avoid loss of shadow detail.

While in ML and using movie mode, you just have to press and hold the flash button on the top left of the prism housing.

It really is great guys isn't it. There hasnt been a very big deal made out of continuos record.
I suppose it hasnt been a big deal for movie makers.
But for us event guys, its a game changer.

Thanks for the bitrate breakdown Colin.

This is the latest version as far as im aware, stable too.
Magic Lantern 0.2.0 RC1 for 550D firmware 1.0.9 - Magic Lantern firmware development | Google Groups

False colours looks like something worth familiarizing myself with. Thanks Chris

I can confirm the 29.59 limit applies to my 550d too, despite earlier claiming that the clip length restriction did not apply to 1080p recording.

I was basing my statement on the Trammell Hudson interview where he made the comment that this was the case. I guess he must have been referring to the behaviour of the 5d.

Using the Jan 22 build myself and really love ML. Simply amazing. Have toyed with a few of the features, but really wanted to kill AGC first. Will probably get a Juiced Link to keep in camera gain low.

False colors
 

Follow up on False Colors:

In the first addition of false colors, in order to get proper false color readings, we were told we had to press the play back button once. Then exit. I thought that had been fixed but it appears not. So after staring ML, and before actually using, just hit the play button (>) once and exit it, and your false colors will be a go for the session.