Timelapse Help

[DJHaze596]

Shot another Sunrise timelapse today & was very disappointed on how it came out.  It keeps  over exposing.  I get my Exposure,  which was 2 second exposure and take a picture every 3 seconds.  worked perfectly.  but once intervalometer & bulb ramping started,  after about 30 Pictures,  it starts to over expose. I tried EV 20, 10, & 5.  Didn't change anything,  than i set it to spot metering and focused for the Clouds.  Still didin't help.  The timelapse i shot before i started at night taking pictures at 5 second exposure and as sun rised,  my Settings changed.  It still started to over expose after a while,  but atleast it was working.  Idk it wasn't working right this time.  Yeah i'm shooting RAW but its so washed out in the clouds,  your not going to be able to recover that in Post.  I know once that sun peaks,  its going to be a little washed out.  But this was before it was peaking,  Also it doesn't correct the exposure.  You'd think it would correct the exposure in the next shot if the previous one was over exposed but it didn't so i had to keep stopping it after about 100 shots to fix the exposure which means on playback i'm going to have skips.  Any ideas?

[Haliburton]

After an exhaustive search, I've not been able to find a dedicated help topic for time lapse film makers, so please excuse me while I hijack this appropriately-named thread.

Mods, please move this, if in fact there already is such a thread. In any event, there are a number of lonely requests for help, which might best be consolidated into one thread.

So: here's my 2¢ :

With respect to time lapse film making, the Magic Lantern feature I'm most thrilled about is to use RAW video with FPS override, to vastly reduce the number of shutter cycles the camera is bruised with.

Unfortunately, there seems to be a lower limit to exposure override, so that one cannot even approach 180º shutter angle with intervals approaching the current 0.2 fps (ie. one frame every five seconds) limit.

During daylight, people use ND filters and/or polarizers to allow long exposures.

In this example, I have FPS override set to 1 fps, but the slowest shutter speed that I can set is 1/10 second:



I'm wondering if there are technical hurdles which can be overcome, to allow even longer exposures to be used via exposure override?

Also interesting is that when shooting RAW video, if Global Draw is on (bad idea), the red crossout indication of you-are-not-recording, stays drawn during recording:



Further differently additionally interesting, is that even at 1 fps, the on-screen indication is that the card is still being written to at the 60D's limit of just over 20 MB/s:

[brapodam]

I was quite interested in ML's capabilities to shoot time lapse sequences without moving the shutter mechanism, and I have done some testing.

H.264 video, FPS override, Video Auto Exposure
-Images were okay, but lacked clarity and dynamic range of RAW video
-Have to have appropriate ND filter
-No flicker

Silent Pics, Auto ETTR, post-deflicker
-Might be an issue with my settings for auto ETTR or post deflicker, but the post deflicker exposure changes made all my images horrendously underexposed, as described here: http://www.magiclantern.fm/forum/index.php?topic=6649.0
-No ability to record with screen off; internals of camera heat up too fast as a result, producing images with a lot of noise
-Recently there has been a change to make powersave more aggressive when shooting silent pics, but if you enable screen off in powersave, the screen will not come on in time for Auto ETTR to change your exposure, rendering it useless.

RAW video, FPS override
-Shutter speed too limited. You'll also need an appropriate ND filter for the light conditions
-Longer intervals results in longer exposures, which can produce more noise
-Has ability to record with screen off

RAW video, Manual ETTR (put it to set and press it every time you see the ETTR hint change), with this mod http://www.magiclantern.fm/forum/index.php?topic=6451.0
-Exposure changes too drastic
-Due to screen not being able to be off for too long, internals of camera heats up, noise becomes a problem even at low ISOs

RAW video with video automatic exposure
-Camera shoots at non-native (pushed/pulled) ISOs, which are useless in RAW video. As a result, exposure changes are drastic (since exposure only really changes once it hits the next base ISO)
-Has ability to record with screen off

RAW video with Aperture Priority mode, Gradual Expo, with this mod: http://www.magiclantern.fm/forum/index.php?topic=6451.0
-Did a short test at home, and flicker seems to be less of a problem. Still visible but it could be because the exposure change I tested was too much (or my Gradual Expo setting needs to be tweaked)
-I believe shooting RAW video in photo modes was disabled in the more recent RAW video builds, but if you use the mod, your raw video module will be the old one
-Has ability to record with screen off
-EDIT: After further testing, this still produces flicker. Less noticeable, but there still is flicker. There might be a possibility of tweaking the mod further to increase compatibility with gradual expo.

Silent Pics, Post Deflicker, Aperture Priority Mode
-Again, could be my settings for post deflicker, but it seems to choose exposure offsets that make the images way underexposed
-If you don't use Lightroom, it becomes extremely challenging to do anything (see below)
---As far as I know, there is no way to do image adjustments on the DNG files directly before post deflicker
---This means you'll be doing image adjustments on the output from ufraw-batch, which have limited dynamic range compared to DNG files
---Many image operations just don't work as well if you're not editing raw files. At least for me, things like noise reduction produce crap results compared to raw/dng files; they become either too soft or you don't remove enough noise

[Haliburton]

mmm, lots to chew on, thank you @brapodam!

FWIW, while recording RAW time lapse video, I close the swing-out monitor of my 60D, just far enough that the monitor switches off (not quite closed).

Also using eBay special external power adapters for both the T3i and 60D.

"I believe shooting RAW video in photo modes was disabled in the more recent RAW video builds..."

I was completely unaware of this ability in the first place?

Thanks for the link.


In other news, though with my cards formatted ExFAT, I no longer have the 4GB file-size limit, my RAW time lapse sequences still halt recording exactly 1/2 hour from start.

Is that a hard-coded Canon thing, or is there a workaround: anyone know?

[brapodam]

mmm, lots to chew on, thank you @brapodam!

FWIW, while recording RAW time lapse video, I close the swing-out monitor of my 60D, just far enough that the monitor switches off (not quite closed).

Also using eBay special external power adapters for both the T3i and 60D.

Why do you have to close the screen? I set powersave to the info button, so I just press it when I start recording. If I want to check something, pressing info again wakes the screen.

"I believe shooting RAW video in photo modes was disabled in the more recent RAW video builds..."

I was completely unaware of this ability in the first place?

Thanks for the link.

I was not aware of this ability until I saw the changelog. The change was recorded here: https://bitbucket.org/hudson/magic-lantern/commits/5155c8dbe34c8369e8e0dd74e272fa1ab667c6a4

In other news, though with my cards formatted ExFAT, I no longer have the 4GB file-size limit, my RAW time lapse sequences still halt recording exactly 1/2 hour from start.

Is that a hard-coded Canon thing, or is there a workaround: anyone know?

I don't know if movie auto restart will help. I've never really tried that since I never really tested long enough sequences to bust the 4GB limit.

[Haliburton]

Why do you have to close the screen? I set powersave to the info button, so I just press it when I start recording. If I want to check something, pressing info again wakes the screen.

It's just a routine I got into with regular film making: switches the view on or off without the slight jiggle that pushing a button, however carefully, can cause. Especially visible when filming with telephoto lenses. Again, I swing the display _almost_ closed: no snap into or out of position.

I was not aware of this ability until I saw the changelog. The change was recorded here: https://bitbucket.org/hudson/magic-lantern/commits/5155c8dbe34c8369e8e0dd74e272fa1ab667c6a4

So is the ramification of this, that one can film in raw, using still auto exposure modes such as AV, or M with ISO being auto?

I don't know if movie auto restart will help. I've never really tried that since I never really tested long enough sequences to bust the 4GB limit.

While my 60D was cutting out at the 1/2 hour mark (1800 frames at 1 fps), movie auto restart was set to "on."

-  -  -

Blurring the line (what line?) between timelapse and undercranking, I wondered, what's the maximum frames per second that I can film continuously at the maximum 16x9 pixel dimensions (1728x972) that the 60D can capture in raw video?

I took the ML displayed data rate required for 24 fps, divided by the 20 MB/s the camera can write, and it came out to 7 fps. A bonus is that at 7 fps, 180º shutter (1/14 second) can be set:


For natural settings in the driving rain (and without cues like trees jerking in the wind), there really isn't any context to the viewer that the film is undercranked, and as can be seen by the empty buffer (stripes at the top of the display) and running time of 2min 26sec (and counting), one can indeed film at close to full HD 1080p indefinitely... at this lower frame rate:



Yes, it's not "proper" full-motion video, but sometimes constraints open creative possibilities, just as many of us are discovering the joys of widescreen film making and shorter takes (34 seconds at 1280x544), because that's all these SD cameras are capable of in RAW, so far.

[brapodam]

It's just a routine I got into with regular film making: switches the view on or off without the slight jiggle that pushing a button, however carefully, can cause. Especially visible when filming with telephoto lenses. Again, I swing the display _almost_ closed: no snap into or out of position.

I don't do normal video, I only ever used video for time lapse purposes. I may venture into normal video in the future, but not for now. For time lapse purposes, you can press the button during the frame interval, so the camera shake during the button press is a non-issue unless your frame interval is very short.

So is the ramification of this, that one can film in raw, using still auto exposure modes such as AV, or M with ISO being auto?

I do not recommend using auto ISO. When ISO is auto, gradual exposure does not work, so you will experience flicker in your video. Gradual exposure, however, can change your ISO, so if you are referring to that, then yes, it's sort of an Auto ISO

[brapodam]

After all my testing, I think that the best way to do it currently is to use Silent Pics in Aperture Priority mode with post-deflicker. Processing will have to be done in Lightroom or ACR for the best possible results (editing DNGs directly rather than output files from ufraw, which lack the flexibility of raw files).

If anyone has a workflow that works (for editing files before post deflicker exposure adjustments) without Lightroom or ACR, do share it 

Of course, if your time lapse does not involve any exposure change, the RAW video frame interval mod works pretty good.