PDA

View Full Version : Magic Lantern on Canon EOS 550D / T2i - great for extreme low light video



Olivier Staiger
04-02-2012, 03:01 AM
I recently discovered Magic Lantern, a firmware that runs alonside the original firmware of my Canon T2i, booting from the SD card.
http://magiclantern.wikia.com/wiki/Magic_Lantern_Firmware_Wiki


Playing with it now. I almost was going to erase it, as I first found it to be too complicated, bringing too many settings and I might get confused. But for stormchasing it has a few nice features specifically, such as FPS override, so in FHD 1080 video instead of being stuck at 25 or 24 or 30 fps, I can go as low as 4 fps, with exposure times instead of 1/30 sec. now going as long as 1/4 of a second. This can be great for shooting storms at night, in extreme low light conditions. However, you must film without sound . Also, it shoots at 4 fps but the playback is still 25 or 30 fps, so it actually gives you a low-light timelapse shooting. Of course with specific software you can stretch it back to 4 fps, e.g. with the Windows freeware Live Movie Maker you can set the clip to play back at 0.125 slowmotion, so it plays at a spead close to the 4fps originally used for shooting. So, in a dark night storm, you can film at 20 fps, or 15 fps, or 10 fps or as slow as 4 fps and the exposure time of the frames are stretched accordingly, and you may choose afterwards if you want to use this for timelapse-at-night or to stretch it back to normal speed. Also even if the video is not too good to keep, you may be able to video shoot a tornado at night and keep a video still from FHD, which is still 2 MB in size. And I mostly use a lens that goes down to f/3.5 , but when using a faster lens such as 50/1.4 it really explodes lowlight video. Looking forward to seeing clouds and storms at night now. Anyone here played with that already ?

another feature I like also is the motion detection, photos are shot when there is motion, that can be brightness variations, so I wonder if I can use it for shooting lightning in daytime ? Indeed shooting lightning at night is rather easy and I had good results with it
see http://www.klipsi.ch/blitze/lightning.htm but in daytime it is not so easy, I have caught a few but more by luck than tech, so I look forward to testing the lightning detection capability in daytime storms of Magic Lantern. Has anyone here tried it ?


Magic Lantern works on various EOS models, The one used for the 550D is here :

http://magiclantern.wikia.com/wiki/Unified/Install


important: first update the Canon EOS firmware to the latest version.

here's the user guide. Agreed, it is 'complicated', and not recommended for beginners, it is best to first know your T2i inside out and start using this later. And , it is not guaranteed to work, if you do something wrong, it may kill your camera, that firmware is not allowed by Canon.

http://magiclantern.wikia.com/wiki/Unified/UserGuide

Skip Talbot
04-03-2012, 04:45 PM
Olivier, does dropping the framerate extend the movie recording time? I know the camera is limited to recording up to 4GB files, and was wondering if dropping the framerate extended the time it takes to hit this file size. How about issues with overheating the sensor running in movie mode that long? I haven't gotten around to loading Magic Lantern onto my 60D but am definitely planning on it for timelapse and low light video. Thanks for sharing

Olivier Staiger
04-04-2012, 02:27 AM
Olivier, does dropping the framerate extend the movie recording time? I know the camera is limited to recording up to 4GB files, and was wondering if dropping the framerate extended the time it takes to hit this file size. How about issues with overheating the sensor running in movie mode that long? I haven't gotten around to loading Magic Lantern onto my 60D but am definitely planning on it for timelapse and low light video. Thanks for sharing


I have to verify this specifically.

from the usermanual: quote:

How do I record for more than 12 minutes?
• Lower the bitrate (CBR 0.4 will let you record continuously for 30 minutes).
• Use Movie restart, but you will lose a few seconds when a new file is created.
• To record continuously for more than 30 minutes, you need to use a HDMI recorder. Select
ClearScreen: Always to hide all graphical overlays and enable Half-press shutter:
Every second to prevent the camera from shutting down.
Technically, there’s no 12 minute limit. There’s a 30 minute limit and a 4 GB limit, whichever
comes first. With default bitrate settings, the 4 GB limit is reached after around 12 minutes
(more or less).

end quote

so the limit seems to be the 4 GB file, and if you lower the bitrate you may get beyond the 12 minutes normal limit.

Now,. when shooting at 4fps in low light, and then playing it back, it plays back as a timelapse, fastforward, because it is shot at 4fps but playback at 30 or 25 fps. However with software, such as windows live movie makers freeware, you can slow it down so it comes back to normal or near normal. Thus, I could imagine that when I shoot e.g. 2 minutes at 4 fps the videofile should be smaller than if I shoot at 30 fps, and therefore it takes longer to reach the 4 GB limit , so you should be able to shoot longer. I will verify this.

also, important: when shooting at lower fps, you have to turn off the sound, so you shoot mute.

you can also shoot lowlight nightshot WITH sound by adjusting the gain, but it quickly gets noisy. Still, it may be useable occasionnally. Fast lens will give better result.

Olivier Staiger
04-04-2012, 03:22 AM
update:
I just did another quick test:

SECAM 30fps, shooting 30 seconds MUTE FHD 1080 video resulting in a file of 166MB ,

but at 10 fps override it resulted in a filesize of only 54 MB ( = that's one third, which sounds pretty logic )

and at 4 fps the file was only 20 MB ( about 2.5 x less than the 10 fps, logical again ).

As a result the 4GB limit is far far away when shooting video at fps override to very slow shutter.












Olivier, does dropping the framerate extend the movie recording time? I know the camera is limited to recording up to 4GB files, and was wondering if dropping the framerate extended the time it takes to hit this file size. How about issues with overheating the sensor running in movie mode that long? I haven't gotten around to loading Magic Lantern onto my 60D but am definitely planning on it for timelapse and low light video. Thanks for sharing


okay I just did a quick test . For comparison:

shooting 1 minute MUTE video in SECAM , FHD 1080 at 30 fps, at 1/30 exposures, aperture 2.8, ISO 100, resulted in 313 MB file ( I presume the file is probably even larger if filmed with sound)

Same scene, same settings but FPS override to 4 FPS , one minute shooting at 4 fps ( resulting in 1/4 sec. exposure times for each frame ) would result in about 8 seconds video timelapse if played back at 30fps, or 1 minute non-timelapse video if played at 4fps, but now the file is only 42 MB in file size.

so, a 4fps video is about 8-9 times smaller in filesize than normal video. As a result, you need much longer than 12 minutes to reach the 4GB limit, Thus I would think that yes you can probably shoot longer than 12 minutes video. To be tested .

Olivier Staiger
04-04-2012, 04:24 AM
update, magic lantern now has an update with FPS as long as 0.2 instead of 'only' 4FPS !!!
now that's really cool, amazing UP to 5 seconds exposures on each frame in video. wow.


http://groups.google.com/group/ml-devel/browse_thread/thread/b52839bfdf48ee54

will try it next night

Olivier Staiger
04-04-2012, 08:20 AM
so here I show an example, of how low light capable it gets in fps override slow shutter. first shooting at 24 fps with ISO 100, closing window it gets pitchblack, then switching to 6400 ISO , still hardly nothing visible, but then I go fps override to 10, 5 and 1 fps, and the black scene lightens up.

http://youtu.be/pH6H6uiNCgQ

Skip Talbot
04-04-2012, 10:48 AM
That is super sweet. I was shooting most of my timelapse on my camcorder, speeding it up to the equivalent of 1.8 fps. I'll probably just use my 60D now for timelapse as the picture and low light quality is going to be superior and I'd love to be able to use the 10-22 for timelapse.

Karen St John
04-04-2012, 11:28 AM
I wonder if they wiil have it for the EOS 7D?

Terrence Cook
04-04-2012, 11:58 AM
I have been quite hesitant to play with this, but I see no way to avoid after the latest update. Thx for the info and thorough testing Olivier!

Matt Tottle
04-04-2012, 02:56 PM
The 4GB per file is actually a limitation of the file system used by SDHC cards (FAT32). The newer SDXC cards (exFAT) do not have this issue. The T2i is capable of using SDXC, so you should not hit the 12 minute ceiling if you use a 64GB or larger card.

Sent from my Samsung Galaxy S II using Tapatalk

Olivier Staiger
04-04-2012, 03:30 PM
67816782

two videostills . Camera EOS 550D. Lens Tokina 11-16 f/2.8 . Setting at f/2.8. ISO 6400.
the dark image , at night, is at lowest lowlight originally possible, in 24fps at 1/30 sec shutter speed.
then
the second image, bright, is with FPS override shot at 1 fps, resulting in 1 second exposure times
Sure there is some noise at ISO 6400 but this was with a 2.8 lens, now if I used a 50/1.4 lens I could easily use ISO 3200, 1600 or even 800 and reduse noise. Also using B/W instead of colour may reduce some minimal amount of noise.
anyway, I think this could be interesting for shooting tornadoes at night when there's no powerflahes.

Thomas Dolmer
04-04-2012, 04:01 PM
What these guys have managed to get out of the firmware is amazing. I have followed the Magic Lantern project for some time with the purchase of a 60D in mind. HDR video, bulb ramping time lapse, focus peaking & stacking - the list goes on. And now the new fps setting....
And the sweet thing is that your original canon firmware is safe because the Magic Lantern firmware is loaded from the sdcard during startup.

Ryan McGinnis
04-07-2012, 11:29 PM
What's great is that this software works backwards to the 50D -- which without this firmware can't shoot video at all. With this firmware, it will shoot video without sound. This isn't a big deal, since you can record sound seperately and sync it up later in your favorite video editor -- if you're cheap like me, you can even use your iPhone as a mic, which works surprisingly well (that thing has a rather powerful noise cancellation system).

The "shoot a timelapse without firing the shutter" thing is great in that is doesn't wear out the shutter. Though note that you get much better image quality if you shoot the timelapse as stills instead of as video. I don't know why this is, but 1080p video looks nowhere near as good as 1080p stills.

Derek Weston
04-19-2012, 01:41 PM
What's great is that this software works backwards to the 50D -- which without this firmware can't shoot video at all. With this firmware, it will shoot video without sound. This isn't a big deal, since you can record sound seperately and sync it up later in your favorite video editor -- if you're cheap like me, you can even use your iPhone as a mic, which works surprisingly well (that thing has a rather powerful noise cancellation system).

The "shoot a timelapse without firing the shutter" thing is great in that is doesn't wear out the shutter. Though note that you get much better image quality if you shoot the timelapse as stills instead of as video. I don't know why this is, but 1080p video looks nowhere near as good as 1080p stills.

Stills would have higher resolution.

Ryan McGinnis
04-19-2012, 04:53 PM
Indeed! But what I mean is that even with the resolution downsampled (either via camera settings or manually in Photoshop later), you're still better off shooting stills than using the video timelapse feature. The way the camera captures video information seems to be entirely different than the way the camera captures photo information.

Skip Talbot
05-11-2012, 11:51 PM
Finally got around to playing with this mod on my 60D. I did a side by side video comparison with my camcorder in extreme low light to see how the performance compares. The motion is significantly blurred by the low framerate of course, but that shouldn't be an issue when shooting storms, and I'll probably be making timelapses out of this anyway. Camcorder is a Sony HDR-XR500 shooting at 60 interlaced frames per second (left) compared with a Canon 60D and a 50mm f/1.8 ISO 1600 shooting at 4 progressive frames per second (right):


http://www.youtube.com/watch?v=p9nQmqfCMAI