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 Magic Lantern ETTR Timelapse 
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Joined: Tue Jul 02, 2013 1:47 pm
Posts: 60
Location: Wirral UK
Post Re: Magic Lantern ETTR Timelapse
I guess you've answered these questions for yourself by now but I'll answer what I can, better late than never I hope.

Test shots allow ETTR to zero in on the correct exposure. I've never tried using live view mode so can't tell you if this would work but you certainly don't need to. Just take a few shots until the exposure has stabilised. The version I use beeps once for a correct exposure, twice to indicate it's out but it has scope to correct it, three means it can't get a correct exposure with current settings. I don't know what the numbers you speak of refer to.

Newer versions of ETTR supposedly will automatically adjust the interval to accommodate longer exposures. So in theory you could set the interval to 5 secs and the max exposure to 15 secs, and as the exposure time increases the interval will stretch to allow this. If you read back through this thread, or the thread on ML, then you can see this has not worked for me. Using the ML intervalometer I find I need at least 4 secs between the end of one exposure and the beginning of the next. The fastest I can reliably go is an interval of 8 secs with a max shutter of 4 secs. But I'm basing this on old versions of ML and as Karl says, you should probably look for answers to this on the ML forum.

Highlight ignore is one of those things you need to get an intuitive feel for. I'd probably start with the default 0.2% for most subjects. If you're shooting into the setting sun, on a clear evening, with a fairly wide angle lens, then you may wish to increase it to 0.5%ish to avoid black foreground. If the sun is backlighting clouds then 0.5% may clip more than you'd like, it's a bigger chunk of the image than you might imagine. If you're using a longer lens then you may need to go for 1% or more. As I say, lots of real world factors, not something there is simple rules for.

For a day to night shot I would try settings like those Karl suggests. I had another go at the Hilbre tides shot (below). This was a 16 sec interval with a 11 sec max exposure. Bare in mind that ETTR shots won't look like this straight out of the camera. It's exposing to make best use of the sensor, not to produce images that look right. A considerable amount of manipulation in post has been done to make it look this way. Good luck...


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Wed Oct 22, 2014 2:10 am
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Joined: Tue Jul 02, 2013 1:47 pm
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Post Re: Magic Lantern ETTR Timelapse
We've finally finished the short film that many of these ETTR shots were for (some even made the cut).


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Sat Mar 28, 2015 3:23 am
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Joined: Mon May 11, 2015 12:44 pm
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Post Re: Magic Lantern ETTR Timelapse
Regarding the above intervalometer automatically stretching when shutter speed reaches interval length ... I also have not seen that work what I have seen is the intervalometer start freaking out at that point because it's triggering shots while there is still an exposure under way. I was told that you always have to have 10 seconds between exposures for the live view and ettr to catch up with a little time to spare. So that means if you plan to shoot from daylight into night you need to have the interval set for night at the beginning ie: 20-30 second exposure times = 30-40 second interval. It's taking exposure time and adding it in to the interval time which threw me off a bit at first.


With all that said I am having a problem with ETTR/Post Deflicker that I'm hoping someone here might be able to assist me with. After much trial and error (the ML forum pages on ettr and deflicker aren't very clear) I was finally able to get ETTR to expose well and I did a few golden hour time lapse tests where the results were very promising and I was able to bring in the XMP deflicker files and have adobe bridge read them successfully. My problem is with cropping ... I like to use lightroom for cropping my images to 16:9 because ACR doesn't specify aspect ratio when cropping. I can bring the files in to lightroom and lightroom reads the metadata from the xmp files but after I crop, develop settings, and copy to the other files all the deflicker data is lost. I relatively new to a digital work flow I spent a lot of time working with 35mm film and B&W so maybe this issue is my shortcoming but if someone could please explain to me what I need to do in post to crop but still keep the deflicker data in tact I would really appreciate it. Should I be using exiftool to adjust any exposure tweaks then exporting the files to jpeg or tiff then cropping the jpeg or tiff files in lightroom? I hope that's not the solution because it seems like a lot of exporting just to preserve deflicker :D Again any help would be very much appreciated.



thank you !


brae


Mon May 11, 2015 1:01 pm
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Joined: Mon May 11, 2015 12:44 pm
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Post Re: Magic Lantern ETTR Timelapse
I am hoping someone here might be able to assist me in better understanding the post deflicker portion of the ETTR time lapse process?....

I successfully shot a golden hour time lapse yesterday evening using ETTR + Post Deflicker modules (using CR2 and XMP files). I work on a MAC and I was able to get the files imported to lightroom (in the thread regarding how too ETTR/Post Deflicker on ML site it says this works) and I got it to read the metadata fine and I even moved the files to bridge to preview for any flicker between frames (it was looking great). Once I cropped my images in Lightroom is where the trouble started (I think). I used lightroom to crop to 16:9 then I developed settings (pasted to all) and exported the files out to high quality jpeg and imported as footage to After Effects. I thought all was well but my final render from After Effects was full of flicker. this has to be a problem on my end I'm just not sure what I'm doing wrong. any insight or suggestions would be appreciated.


thanks in advance!


brae


Mon May 11, 2015 1:51 pm
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Post Re: Magic Lantern ETTR Timelapse
Hi brae, I'm going to test the ML AETTR timelapse soon but looking at the deflicker script, it seems that it only change the exposure value in the xmp file for each picture in order to deflicker the sequence.

Code:
xmp.setProperty(XMPConst.NS_CAMERA_RAW, exposureEnXMP, ev)


In Lightroom, if you copy paste all the settings, it will erase that exposure change (that you can see in the develop module in LR) for all the other pictures and you'll loose the deflicker effect.

I've not test it yet, so I suppose that it's happening.

Just select the Crop setting when you copy paste the parameters in Lightroom and that should work.

Yannick

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Tue May 12, 2015 12:16 pm
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Joined: Mon May 11, 2015 12:44 pm
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Post Re: Magic Lantern ETTR Timelapse
yayasite wrote:
Hi brae, I'm going to test the ML AETTR timelapse soon but looking at the deflicker script, it seems that it only change the exposure value in the xmp file for each picture in order to deflicker the sequence.

Code:
xmp.setProperty(XMPConst.NS_CAMERA_RAW, exposureEnXMP, ev)


In Lightroom, if you copy paste all the settings, it will erase that exposure change (that you can see in the develop module in LR) for all the other pictures and you'll loose the deflicker effect.

I've not test it yet, so I suppose that it's happening.

Just select the Crop setting when you copy paste the parameters in Lightroom and that should work.

Yannick




thanks Yannick (and sorry for my two posts in a row, obviously things got convoluted on my end) ironically I did try just checking the crop settings and it still blew out all my deflicker information in the XMP files. MY solution was to totally abort the post deflicker workflow from ML and use David Milligans Bridge Ramping Script in adobe Bridge which totally kicks butt! :)

the workflow that worked for me was to use ETTR for exposure but ignore the post deflicker information, import files to lightroom, crop to 16x9 then open Adobe Bridge CC update the metadata and bridge saw the crop changes then I ran the Bridge Ramping deflicker script http://davidmilligan.github.io/BridgeRamp/ from the Bridge CC startup Scripts folder and I was good to go with no flicker. I then exported to high quality jpeg using ACR, imported to AE and rendered to apple pro res 422. It was only a 10 second test clip but I was quite impressed with how it turned out. I am very much looking forward to getting out to capture a longer golden hour time lapse maybe this evening.

Thanks again for your reply.


brae


Tue May 12, 2015 1:01 pm
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Joined: Thu Jul 22, 2010 12:03 pm
Posts: 33
Post Re: Magic Lantern ETTR Timelapse
Hi, here is one on my first tests with ETTR Night to Day Timelapses.

Camera : 550D
Lens : Canon EF-S 10-18 mm f/4,5-5,6 IS STM

Camera and Lens Parameters :
Focal Length : 10mm
Aperture : f/4.5 (I wish I had a f/2.8 lens but that is the wider I could go :cry: )
Maximum ISO : 1600 (550D is not good in high ISO, noise starts at 800 and ISO 3200 doesn't help getting more light, it just crop even more the highlights. If I had a 6D I would have put 3200 or 6400)
Image Review : On, 2sec (needed to enable it for ETTR to works)
After starting shooting, I hid the camera display (with the DISP button) to preserve battery (it only shows the previews ofter each shot). The cameras stops after 7hours of shooting which was enough for me.
I also used the Lens Twist Trick to avoid aperture flicker.

Parameters in Magic Lantern
Beeps : OFF (wanted to get some sleep without hearing beeps all the time 8-) )
Interval : 26 sec (the best compromise I could find between getting the most stars I can at night and not a too horrible effect on the day)
ETTR Parameters :
- Trigger Mode : Always On
- Slowest Shutter : 20 sec (which seems to be in reallity 22.6 seconds. With the ETTR process and everything, I should have put 27sec interval to be more secure)
- Exposure Target : -0.5EV (default value was -1EV, -0.5EV seems to expose a little more to the right, that will let me more time before it starts changing the ISO and shutter speed down and loosing some crucial light info)
- Hightlight Ignore : 0.2% (not sure if it was the best value, it's the more difficult parameter to choose)
- Midtone SNR Limit : 6 EV (default value)
- Shadow SNR Limit : 2 EV (default value)
- Link to DUAL ISO : OFF

Here is the final video after many tweaks to get it usable (it's the 1080p version, the final one will be 4K):



My Camera and Lens are not good enough for shooting stars (but it forces me to try to understand how I could use it to maximize the quality and minimize the noise). I've done also a lot of post prod (with Lightroom, LRTimelapse and After Effects) on it to get rid as more as I can of the light pollution and to see the most stars as I can. I cheated a lot on After effect ;) and speed up the video at 2x (but I used all the pictures to add some sort of stacking to increase brightness and decrease noise). I didn't used the Bridge script for deflickering but used the new visual deflicker in LRTimelapse 4 which is truely awesome. Magic Lantern and the ETTR module seems to write wrong EXIF data for the shutter speed in my case. On my camera, it uses 1/3 and 1/2 stop intervals but only choose 1/3 intervals in the EXIF info, so I have jumps that are not repercuted in the EXIF (LRtimelapse visual deflicker was able to correct that problem).

Here is the difference between the original (untouched pictures out of the camera) and the final result :



The original pictures don't seems so overexposed as I think it would be with ETTR (on the day for exemple, they are not that bright), maybe I missed something.

If you have some advice to make this timelapse better, I'm open to any critics.

Yannick

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Sat Jun 06, 2015 9:54 am
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