Working With Magic Lantern Raw

Working With Magic Lantern Raw

I’ve recently been shooting some pick up scenes for our short film Mother’s Boy. We opted to use my Canon 5dmk2 and the Magic Lantern raw video software to match up with some footage shot on a Canon C300. I wanted to write a bit about our experiences of using ML raw for a real world, low budget production.

What is Magic Lantern raw?

For those that don’t know, magiclantern.fm have created software for Canon DSLR cameras that, amongst other things, unlocks the ability to record raw video files. This means that each frame of video is a 14-bit raw image, with all of the flexibility of editing raw photos in Photoshop.

Raw Editing

Raw images give you a huge amount of flexibility to alter the image in post production

The quality and detail of the footage is absolutely fantastic. The reason we chose to use the Magic Lantern software was to match up with footage that had been shot on a Canon C300, and the image quality was certainly similar to, perhaps in some ways better than that of the of the £10,000+ camera.

There are downsides though, the raw image quality comes at the cost of huge file sizes. We were filming for just over 2 days and ended up with around 450gb of raw clips! To put that into perspective, it’s about the same size as of all of the footage  from our original 9 day shoot using the C300…

If you’re on a slower computer you probably won’t be editing using the raw files themselves, you’ll need to create Quicktime ‘proxy’ files which can take a long time.

To give you an idea; using my 2008 Macbook Pro it has taken us an entire week to process our 2 days worth of footage! This is such a huge amount of time when compared to cameras such as the Black Magic Cinema Camera which record editable ProRes clips natively. This means that you don’t need to convert anything and can start editing with the clips straight from the camera.

Edit: You can half the time it takes to create the proxy files by setting them at half resolution. Da Vinci Resolve does this really well and you can easily create a proxy at half resolution that is scaled up to 1920 x 1080.

As for storage of the raw files, this is going to be costly no matter what. You will want to retain the raw files for grading, even if using proxies for editing.

Da Vinci Resolve

This is only for half a days worth of footage!

There is also the issue of reliability. I must admit I was quite nervous about using Magic Lantern for an actual production. The software is being created by developers in their spare time for the love of it, it isn’t subject to the rigorous testing which companies like Canon put their cameras through.

On the whole though it’s been really reliable and it’s remarkable what they’ve managed to achieve. That’s not to say there weren’t issues and I’ve had to spend a lot of time trawling the internet for answers. Things are improving all the time though and all of the issues I’ve had seem to stem from the fact that I was using older versions of software such as RawMagic. The important thing is that all of our footage is present and correct and aside from the time it takes to process the footage I would go so far as to say that (in my experience) ML raw is suitable to be used in a real world production.

Important: ML raw is a work in progress and is being continually improved. If you do a Google search you’ll find lots of articles saying that it isn’t reliable enough to use in a serious way. If you do read an article questioning the reliability of ML raw it’s very important to pay attention to WHEN it was published, as things may have moved on since then. In fact if you’re reading this article in the future then some of the things I mention as drawbacks might even have been solved! See below for the list of errors I have encountered and found solutions for.

Why did we choose Magic Lantern raw?

The main reason we considered ML raw, in spite of the drawbacks, was that we didn’t have the budget to hire a C300 for our pick up scenes, but still needed footage that would look as good. There are other cameras that are slightly cheaper than the C300, which can do similar quality, but I already owned a Canon 5dmkii and some nice lenses so using ML raw meant no hire costs in terms of equipment. All we had to do was buy a couple of fast CF cards and a new hard drive, so this was going to be by far the cheapest option for us.

Before committing to using ML raw I did some tests of whether the standard H.264 clips from my 5D would suffice for this project, but it really does look a bit pants when compared side by side with the C300 or ML raw footage.

Raw vs h264

A comparison of the standard DLSR video footage & the Magic Lantern raw

We were stuck for budget so the only really feasible option for us was to shoot with the Magic Lantern hack and hope that it would turn out okay!

The Results


Note: If possible please watch on Vimeo in HD

As I mentioned, quality wise there is no issue whatsoever and for the cost of the 5dmkii (under £1000 as opposed to £10,000), and the fact that Magic Lantern software is completely free, you really can’t complain. There is a bit more noise than I had hoped for (I’m not sure if I had quite the right ISO settings in the Magic Lantern menu). Other problems with the 5dmkii such as aliasing are still there, but the main issue you’re faced with really is the workflow and that the image quality comes at such a massive price in terms of file size.

In the interest of helping others I’m going to try and summarise my experience, and collate the various useful bits of information I’ve found.

Will shooting with Magic Lantern raw harm my camera?

My first question was whether there was any chance using ML raw might damage my camera with having to write such huge amounts of data per second? However, this was based on a misconception about how the camera records video. In fact the camera always captures video in raw format, even when you’re not using Magic Lantern. In the standard Canon video mode the raw is compressed into a lower quality h.264 file, and then the raw data is discarded. All Magic Lantern does is save the raw data stream to the memory card. In fact the camera is actually doing less because it doesn’t need to compress the video, so it actually requires less processing power in that respect!

In terms of data rate, so long as you have a memory card that is fast enough (see below), the camera will have no trouble keeping up, it’s actually rated to be able to record higher mb/s than is required for raw video.

Is it difficult to use?

Once you’ve installed Magic Lantern raw and set your preferences it’s quite straightforward to shoot with, it’s pretty much just the same as using your DSLR normally.

Installation is a little fiddly and it’s best to follow along with a tutorial.

A guide to installing Magic Lantern

Some of the advanced options are more confusing, as I say I had some issues with setting the ISO. More on this below

Which Memory Cards Should I Use?

A general consensus is that the best cards to use are Komputerbay 64gb 1000x cards. You’ll need at least 2 to be able to shoot continuously, 3 or more if you don’t want to be overwriting the CF cards on set.

You will also need a fast card reader and a computer with USB 3.0 ports. With this set up it took us around 15 mins to offload 64gb of footage.

How much footage you can get on a card will depend on the resolution you record at. On the 5dmkii you can shoot up to nearly 1920×1080 at 25fps if you wish, though at this resolution the camera may not be able to write the data fast enough and may stop recording mid-take. Our film is a wide 2.35 aspect ratio, which means the image is smaller in size than full frame 16:9. We were able to get around 10 mins of footage per card and we didn’t have any issues with buffering at all.

Ratio

Ideally we would have shot 16:9 so there would have been room to re-frame the shots in post production, but in this instance we felt that the trade off was worth it to ensure that every clip was recorded safely.

What else do I need?

Hard drive(s)! Big ones, again with USB 3.0 connections and a computer with USB 3.o ports.

Over 3 days of shooting (two of which were half days) we managed to record 450gb of raw clips!

Shooting Tips

1. Highlight Recovery

In my experience, it’s possible to significantly overexpose the image by a few stops and regain the lost highlight data. But doing so may introduce some strange flickering artefacts in areas of high contrast. I don’t know if this is specific to my camera, the 5dmkii, or a more general issue, but it’s something to be aware of and it’s a good idea to test this out for yourself to see how far you can push it.

Histogram

EDIT: This may be something to do with using the highlight recovery option in the Adobe dialog box, as this is functionality for stills cameras. Using other software such as Da Vinci resolve’s highlight recovery option may produce better results.

2. Noise

If your DSLR suffers from noise then the raw will too, even with raw it’s still a good idea to expose your image properly, as you can’t recover underexposed areas too much without introducing noise.

Apparently it’s best to use Magic Lantern’s own controls for ISO as this results in less noise. But this just confused the heck out of me and I’m not sure if I had the right setting. I’m going to do some more research and tests on this before using the ML raw again.

Noise

3. Playback

At present, it’s not possible to play back raw clips in camera. Nor is it possible to play them back instantaneously on your computer once offloaded.

Playback

Post production

Processing the raw clips is relatively straightforward once you know how, but unless you have a powerful computer it’s going to be a sloooooow process.

I’ve estimated that on my Macbook Pro (2008) it’s going to take more than 100 hours to convert our 3 days worth of footage! Though my computer is quite old and sluggish and if you have a more powerful one that time can decrease significantly. You can also decrease the time by setting resolution of your proxies to half in Da Vinci Resolve.

This video shows the workflow I used for converting raw files into an editable format (I didn’t make the video). The helpful video also covers some of the common issues you’ll be faced with such as files that are larger than 4gb.

Common Issues  (5dmkii, Mac OSX)

To save you hours of internet trawling, here are solutions to some common issues you may come across:

1. Files Bigger than 4gb

Files bigger than 4gb (ish) get split into 2 files, these are supported in RawMagic v1.0 and above (see video above).

Files bigger than 4gb in Magic Lantern raw get split into 2

Files bigger than 4gb in Magic Lantern raw get split in 2

2. Vertical Lines Appearing on DNGs

This seems to be a bug with RawMagic, make sure you’re using the latest version. If you already are then the issue can simply be solved by simply restarting RawMagic and reconverting the clips. Lines should disappear.

Vertical Lines Error in RawMagic

The lines look something like this

3. Pink Noise of Doom

I freaked out when I saw this… around 10-15 of my clips that were over 4gb appeared to be corrupted and I was struggling to find any posts with relevant solutions. It turns out that I was able to solve this by simply upgrading to version 1.0 of RawMagic (Mac App Store)

Solution for pink noise on some DNGs with Magic Lantern raw

Solution for pink noise on DNGs with Magic Lantern raw

Summary

Would I recommend shooting raw video on a DSLR? Absolutely, but it does bring about an interesting dilemma.

On the one hand it’s great because it makes you really consider what you’re shooting. You can’t play the clips back which means you have to really pay attention, and since you’re aware of how long it’s going to take to process, or even view your footage, you feel compelled to make every frame count. This can only be a good thing in the age of disposable digital footage, if you have the opportunity and the time available I would recommend trying raw shooting.

Using Magic Lantern On The Set Of Mother's Boy

Using Magic Lantern On The Set Of Mother’s Boy

On the other there is the question of whether you’re going to be in a position to handle the footage.  Ordinarily if you were to shoot raw it probably would mean you have the equipment and budget to be able to deal with the post production side of things, but we’ve just shot raw and it’s really pushing the limits of what our equipment can deal with (not to mention the time we have available). Obviously the more you shoot the more time is required to process the footage. For a 9 day shoot, if you’re on an older computer such as mine then i’d estimate you’re talking around 2-3 solid weeks of processing the clips into an editable format!

If you’re considering raw I’d suggest doing some test shots and seeing how long it takes to convert them on your own computer.

If you’re a) on a longer shoot b) don’t have a lot of time for processing or c) don’t have a decent computer to process the footage then I’d suggest a camera which shoots higher quality compressed images such as the Canon C300 or Black Magic Production Camera.

For us though, using Magic Lantern was our only real way to get footage of this quality. If it didn’t exist we’d pretty much be stuck with the standard, fuzzy 5dmkii footage, so inspite of the drawbacks I’m extremely thankful that it exists!

We’re only using raw to get sufficient image quality to match our C300 footage, which was shot in a compressed format (8-bit ProRes). We’ll be converting the raw files to ProRes before colour grading them anyhow and so won’t be utilising the full grading potential of the raw . With the spec of my computer we wouldn’t be able to grade the raw, even if we wanted to…