Greetings .... I'm 'new' to magic lantern, though I've been reading the forums on and off for a couple of years ... The following account *may* be of help to some who are starting out ...
Naturally I was fearful, worrying about possible camera damage. Trying to figure out *which version* of M/L to load was a nightmare and I pondered this for a long time. Would it be the December 24th, 2018 nightly build? That *seems* rather dated now. Then again, would I risk a more recent 'experimental' build? Decisions, decisions. Well, I finally chose the experimental version of March 24th 2019. Why? Simply because it offered the ability to record in 10, 12 or 14 bit RAW - straight from the 70D's sensor. Now I must say, I'm NOT an overly 'techy' sort of guy. I'm 'visual', and I prefer to keep things 'simple'.....
So, I got to thinking that this 'cropped' (3x or 5x - whatever) was toooo much of an inconvenience. I just wanted 'simple'. Soon I realized that the largest video 'frame' size M/L would allow me to capture (without the 3x), was 1832 x 776 pixels. That's based on a 2.35 to 1 aspect ratio. So not quite full HD width. But I'd read that you still get great results after up-scaling, so I continued in hope. Well, really the rest is history. At the end if the day, all I was after was a *film look* from the 70D - with it's amazing focus system. Based on this goal, here's how I proceded:
■ Normally, (without M/L), I'd go with 24 fps (like 'real' film), using a fixed aperture of 1/50th of a second (roughly 'twice' the frame rate).
■ Also I find that an ISO setting of 640 - is as high as I can get away with, without introducing too much visual noise. It also happens to be an *ideal ISO* for shooting indoors. In a room with bright natural or artificial light, you get a perfect exposure at f:2.8. Neat.
■ I followed M/L instructions, loading the (3 files) onto a fast SD card, (which I'd formatted first). I used a Samsung EVO 64GB SD card, 60MB/sec write speed.
■ As mentioned, I went with the March 24th, 2019 M/L 'experimental' build. I chose to record at 10 bit, which (I thought) was enough of a quality boost without stressing my camera too much. A more demanding 12 bit capture would mean reducing my frame resolution.
■ 10 bit recordings would give me 1832 x 776 resolution, (set for 2.35:1 aspect ratio), resulting in 40.6 Megabytes of data being sent to the SD card each second. This is the bottleneck of the 70D, since it's limit is 40MB/s throughput to the memory card. 40.6 MB/sec is *just over* the limit, and a test yielded just under 4 minutes before the camera stopped recording. (the M/L 'display' showed that the camera's internal temperature had risen from 26° to 32° during recording). 4 minutes would be ample for most shots, and *if* a longer duration was needed, the frame resolution could be lowered. Reducing to a 1792 x 762 resolution gives unlimited recording time, (the on-screen counter being 'green' this time, rather than amber). I only went to 7 minutes - way long enough, (this time the temperature rose from 31° to 41°). This is to be expected - the internals are working harder than usual.
■ After recording, I removed the SD card but
FIRST WAITING 5 seconds AFTER opening the SD card DOOR. The card is then slotted into a PC.
■ Using the free program called "
MLV App" (a 'RAW to Video' converter from Magic Lantern), just go to 'File' > 'Import MLV' & navigate to (open) your file.
■ In "MLV App"s right-side pane, select 'Fix Bad Pixels' > ON (This does *wonders* for hiding those bright 'hot' pixels).
■ Under 'Debayer Algothithm' I went with 'AMaZE' (which is the default and to me gave the best result).
■ To sharpen or not to sharpen. *Maybe* to just '20' - a tiny boost, to get a little more 'percieved' resolution. But with a sharp lens, I'd leave this at '0'.
■ Set RBF Denoise Chroma to desired level. Around the 40 to 60 range worked best for me.
Bear in mind, this run-down is for a 'basic approach' to quickly get your RAW files into a standard (editable) video file. By default this will output your video as 'REC 709'. You *could* do extra fine tuning with MLV's built-in 'level' and 'color' controls (or do that later in your NLE). You could also choose a 'log' profile for better grading control. You could even output as 'Digital Negatives' (DNG's) for maximum control in software like 'DaVinci Resolve'. But for now - back to basics.■ EXPORT: Click the "Cogs" icon at the top, choose 'Codec' > 'Uncompressed AVI' and 'V210 10bit' (or ProRes 4444 for smaller file sizes).
■ RESIZE: I entered 3664 x 1552 - exacly twice my recorded resolution. I wanted the best I could get straight out of the gate. But you leave this unselected if you're happy with the camera's recorded resolution.
■ I used 'Smooth aliasing' 3 pass. It does a fantstic job smoothing jaggy edges and reducing the high ISO noise. (Long render times though, and if you don't want (nice) Motion Blur at this stage then DON'T select it).
■ Click the folder Icon left of the 'Cogs icon', enter a File Name & Location and hit SAVE. That's it! - Editable files processed from the RAW data. Now it's onto the editing and color grading.
Uncompressed files are large, so I convert them to an intermediate codec inside Vegas, which reduces them to about 1/3 their size. A more economical approach would be to scale them to 1080p directly from inside the *MLV App* if that's the desired delivery resolution. I'm still experimenting, here's some comparisons (all set for 2.35:1),
10 bit recordings:1832 x 776 (largest FF) = 40.6MB/sec of data (Amber display - buffer's fed 0.6MB/sec above what it can write to the card)
test = 3m 50s1792 x 762 = 39.0MB/sec of data (Green display - buffer not being choked)
Unlimited record time12 bit recordings:1832 x 780 (largest FF) = 49.0MB/sec of data (Amber display - buffer's fed 9.0MB/sec above what it can write to the card)
test = 25 seconds1728 x 736 = 43.6MB/sec of data (Amber display - buffer's fed 3.6MB/sec above what it can write to the card)
test = 1 minute1632 x 694 = 38.8MB/sec of data (Green display - buffer not being choked)
Unlimited record time14 bit recordings:1832 x 776 (largest FF) = 56.8MB/sec of data (Amber display - buffer's fed 16.8MB/sec above what it can write to the card)
test = 14 seconds1728 x 736 = 50.8MB/sec of data (Amber display - buffer's fed 10.8MB/sec above what it can write to the card)
test = 22 seconds1520 x 644 = 39.1MB/sec of data (Green display - buffer not being choked)
Unlimited record timeNote: The resolution sizes shown here are what I was able to select on the 70D. They differ slightly to what's shown in the
M/L RAW Calculator https://rawcalculator.netlify.com/calculator_desktop , which indicates '1824' (not 1832) as the maximum available width.
Hoping this helps or inspires some-one ..... And I'd be amiss if I didn't say
a big 'thank-you' to the amazing M/L Gurus who've achieved such incredible results from these Canon cameras.
