Flicker Free ETTR Timelapse: - -Beginners Guide & Basic Post Processing --

Started by RenatoPhoto, May 26, 2013, 01:35:58 AM

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toddex


okay - thanks. I'm using ufraw batch mode, and tried the "temperature" parameter but I seem to be having issues getting the whole sequence to look right - it's either right for the first 75% or for the last 25%. You're probably right I need to ramp it somehow - anyone have experience doing this with ufraw if it's even possible? Trying to avoid switching to bridge since I've got the workflow running pretty much with ufraw...!

Thanks again,

-toddex


ecek2

some of my CR2 files do not have XMP, how to resolve this problem ?


ETTR-problem by agus telo, on Flickr

settings: Interval 5s, AETTR slowest shutter 1", post deflickr XMP

Canon EOS 550D Nightly 2015Mar29
EOS 550D 18-55mm IS - 50mm F/1.8

dmilligan

You need a longer interval, if the deflicker module doesn't have enough time to analyze the image, it won't create the xmp file. Or you can deflicker in post: http://www.magiclantern.fm/forum/index.php?topic=8850.0

keepersdungeon

Quote from: ecek2 on May 30, 2015, 01:57:46 AM
some of my CR2 files do not have XMP, how to resolve this problem ?


ETTR-problem by agus telo, on Flickr

settings: Interval 5s, AETTR slowest shutter 1", post deflickr XMP

Canon EOS 550D Nightly 2015Mar29
Like dmilligan said, usually 6 sec is gd. Or u can disable AETTR then u won't have missing files with 5 sec

squidman90

hey there

I've just run a test sunset time-lapse using auto-ETTR and the post deflick module.
just a couple of questions.

To my knowledge auto-expsoure to the right is a shooting technique to get best signal-to-noise ratio of a photo.

I know it automatically sets the exposure on your camera for you, so the RAW histogram is to right (more lights then darks). I also believe AUTO-ETTR automatically adjusts your shutter speed and ISO to achieve this.

A previous statement on this forum was:
"Take two or three pictures until the RAW histogram ETTR hint is less than 0.2 "

My ETTR hint at the start of the timelapse shooting was less than 0.2  - so when I took a photo it beeped once .  But when I came back to the camera a hour later (night) to check, it started beeping twice after each photo was taken.
Why is this? I know 2 beeps means i have to take the photo again, but why?

Also I want to ramp exposure using shutter speed not ISO, but instead throughout the shooting the camera just kept increasing the ISO automatically and the last photo ended up with a ISO of 3200, which gave me a really noisy photo as Canon 7Ds aren't really good past a ISO of 1000. Whilst the shutter speed remained constant.

Would someone please give me a few pointers, would be greatly appreciated! , Thanks Matt

dmilligan

It's probably beeping twice because the scene lighting is changing, and by the time it takes the next picture there is less light than AETTR expected there to be, and so AETTR is letting you know the photo was slightly underexposed.

The shutter speed isn't changing because either: you reached the slowest shutter set in the AETTR menu or you had AETTR set to only change ISO.


squidman90

Quote from: dmilligan on June 15, 2015, 12:56:57 PM
It's probably beeping twice because the scene lighting is changing, and by the time it takes the next picture there is less light than AETTR expected there to be, and so AETTR is letting you know the photo was slightly underexposed.

The shutter speed isn't changing because either: you reached the slowest shutter set in the AETTR menu or you had AETTR set to only change ISO.



hey dmilligan thanks for the reply. I read in previous comments, that you can change the ISO max limit in the Canon menu, so I did that (ISO 800). Yes, the scene lighting was changing as it was getting dark, but i was taking each photo at 10 second intervals so it wasn't drastically changing with each shot.  I can't see anywhere in Auto ETTR menu where it says "change only ISO" or something of that nature.

dmilligan

What was your slowest shutter speed set to (and did you have 'link to canon shutter' enabled)? and what was the shutter speed of photos? (and just to make sure, you were in M mode, correct?)

(perhaps you should post a screen shot of the AETTR and/or Modified menus, and list the exposure parameters chosen for photos in the sequence)

If the shutter speed of your photos was equal to the slowest shutter speed you had set in the AETTR menu, then AETTR was behaving exactly as expected, increasing the ISO to 3200 (once shutter speed limit is hit, AETTR begins increasing ISO). You can either increase the slowest allowed shutter speed or get faster glass.

If your photos were overexposed, then you might have had the SNR limits or highlight ignore percentage set too high.

Quote from: squidman90 on June 15, 2015, 10:38:20 AM
Also I want to ramp exposure using shutter speed not ISO, but instead throughout the shooting the camera just kept increasing the ISO automatically
There is no reason to not increase ISO once shutter speed limit is reached. All else equal (shutter and aperture), higher ISOs have less noise than lower ISOs (i.e. the SNR per photon is better with higher ISOs), otherwise they would be pointless.

If you don't believe me, then take two photos of the same subject with the same shutter and aperture and different ISOs (say ISO 100 and ISO 1600). In post, adjust the exposure of higher ISO photo down to match the lower ISO photo (or vice versa) and compare the noise levels, esp. in the shadows. You will find the higher ISO shot has cleaner, less noisy shadows, but it clips to white sooner. If your ISO 100 shot was underexposed such that the ISO 1600 shot didn't clip anything (i.e. underexposed by 4 EV), then you would end up with two identical photos, except the higher ISO shot will have much cleaner shadows. Given the choice between the two, why wouldn't you pick the less noisy one (the higher ISO)?

I assume since your interval was 10s, your slowest shutter speed was probably less than that. If you were somewhere that's rather dark (i.e. not in a city with bright artificial light), once it's fully night, even an exposure of say 32", ISO 3200, f/2.8 might still be underexposed. This is why I like to use a ~45s interval for day to night timelapses with a slowest shutter of "32 (like in this example: http://www.magiclantern.fm/forum/index.php?topic=12330.0 which hit those limits even in the presence of an almost full moon).

squidman90

Auto-ETTR Settings:
Exposure target:-2 EV                                                                Canon 7D   Start of time-lapse: 24mm f/4.0, 1/25, ISO 100, AutoWB
Highlight ignore: 0.1%                                                                                  End of time-lapse: Shutter = 8" (slowest) ISO 800 (which i had set to max)
Midtone SNR Limit: 6 EV
Shadow SNR Limit: 2 EV
Link2CanonShutter: OFF
Link2DualISO: OFF
Slowest Shutter: 8"
Always ON
Intervalometer: ON 13 seconds  Post Deflick: XMP -4EV /50%                     

  << Quick test


hey dmilligan,  thank you for the concise answer (I need to try that ISO experiment). I ran a test time-lapse before I had read your reply though.  As you can see
at the end of the time-lapse the ISO had maxed out to 800 therefore making it really noisy in the image, but hopefully increasing the shutter time next try will fix this.

I should have also turned off auto white balance as you can see the temperatures changing all around the place. Question - I don't think i did the post deflicker in ACR correctly, i did read the instructions on page 1 though. I selected all the photos and corresponding XML files and imported them into ACR. I could see the exposure slider increasing throughout the images (deflicker module doing its job) but as you can see in the video there are the odd few frames that are overexposed?  is the deflicker normally like this or have I missed a step??  Also right at the end of the time-lapse it was pretty much pitch black, though in the time-lapse it looks like quite a lot of light. how can you reduce the exposure when its dark - is a there setting or should I just do it in post manually.

any other suggestions please let me know! I'm going to try another time-lapse tomorrow. thanks matt



Nick

I haven't used ML since a1ex was developing it for the 5dmk3, but once I figured out the new way to bulb ramp with this guide it was pretty much perfect.

First attempt once I got ML 1.2.3 working with my stage 1 dolly:

https://vimeo.com/132007327

Worked great I think, I don't see any flicker. Thanks for the guide!

leandroprz

I noticed AutoETTR tends to "overexpose" my shots when the sun goes down and there's moonlight. It's not actually overexposed because the histogram is far from the edge, so I could bring down the exposure and get a nice exposed image, but I was wondering, is there a way to make the module underexpose a bit the images during night? Less steps in post are always welcome.

I was shooting on a 6D and my settings were:
Exposure target: -0.5 EV
Highlight ignore: 0.1%
Midtone SNR limit: 6 EV
Shadow SNR limit: 2 EV
Trigger mode: Always ON
Slowest shutter: 8"
Interval: 15"

dmilligan


leandroprz

Quote from: dmilligan on July 30, 2015, 06:01:09 PM
Exposure target
But if I change that setting to let's say -2 EV (what I would need for night time), during daylight I'll get an underexposed shot.

dmilligan

Oh, I see what you're asking now. Lower the SNR limits if your night shots appear overexposed. AETTR will keep exposing right and even start clipping highlights to maintain the SNR limits you set.

mattb3476

so i have to use this: http://ufraw.sourceforge.net/Install.html#Mac

to deflicker?

ugh.





also, i really don't even really get Exposure 2 the ---> (ETTR).

i mean, i GET it.  this article was great:

https://luminous-landscape.com/expose-rightf

which is from this thread:

http://www.magiclantern.fm/forum/index.php?topic=5693.0



but, so, the module....

after reading up, i assumed...

i would take the first picture, watching the EV value in the histogram, and overexposing without blowing out highlights i want - and taking this picture then set like the to-the-right tolerance or something.

and then, every other picture would find the best exposure, expose to the right, and then bring the image back the it's ideal exposure, and then save that glorious gloss, hooray.



but that's not what happens.  i have to install a command line program?   :'( :'( :'(  (i try.  but i never finish...  i still don't really get it.)

but as a mac user, then, this one, then..?

http://ufraw.sourceforge.net/Install.html

?

but i am le tired.   :-[

https://www.youtube.com/watch?v=kCpjgl2baLs



also,

if i understand ETTR right (right?), then i'm really rarely going to use it.

because i'm usually already trying to expose for past my camera's range.

so i don't have room to the right.

as in....

QuoteAnd of course not every photographic situation will lend itself to this technique. A shot taken on a sunny day with a cloud, a mountain and a forest will challenge the dynamic range of any camera, and so there will be little opportunity of biasing the exposure toward the brighter tones without blowing out the clouds.

from https://luminous-landscape.com/optimizing-exposure/

mattb3476

here it is, without the deflicker.

https://vimeo.com/135436192

i don't know what's causing the big jumps towards the end.

mattb3476

n/m.  i think i am le confused.

https://www.youtube.com/watch?v=kCpjgl2baLs

night, folks.

and don't forget to unscrew that automatic lens.

dmilligan

Out of all of that giant mess of the 3 previous posts, the only real question I could find was this:

Quote from: mattb3476 on August 05, 2015, 08:30:58 AM
so i have to use this: http://ufraw.sourceforge.net/Install.html#Mac

to deflicker?

ugh.

If you have Adobe Bridge, then you can try this script instead: http://www.magiclantern.fm/forum/index.php?topic=8850.0



If you have a real question, then could please try being more concise and specific, and please spare us all the gifs. It's really hard to figure out what exactly your issue is (or if you even have an issue). Please read: http://www.catb.org/esr/faqs/smart-questions.html before posting anything else.

mattb3476

sorry, friend.  i was just being myself and having fun and was anxious to say hello and start talking with you guys.  i didn't mean to annoy.  but i get it.  i have asked a couple premature, dumb questions over the past couple days.  ...but one or two valid ones, too, i think.

like many of us newbies, i super appreciate magic lantern and am stoked to be settling into it.  it's amazing, and i would give you, dmilligan, for your contributions, a big hug, if i could.

at the same time, it takes a massive amount of reading and tests to understand and talk competently about magic lantern's different capabilities.  and this is coming from the post-supervisor of the production arm of a media agency, who's been working with video for a decade.  is there a place for stupid, newbie, wtf questions in the forums, where there is a "no stupid question" rule?  ...where other people can talk and not have to rely on you developers who understandably have better things to do?

the past week, i have read hundreds of thread posts and a bunch of recommended articles, and am slowly making sense of things.  i'll figure things out.  no worries.  and i'll save my comments for when i'm no longer a newbie.

thanks again.  magic lantern is amazing.

smilemirroreos

Hi there
I'm using ML's deflicker module and I had a problem. :(
The picture seems too dark after applying .ufraw files.
I used the settings of 50% and -4EV just like the article says.



Do I have something wrong(-4EV or...)?
The AETTR works fine on the photo but when I apply the .UFRAW files, it darken the image too much.

P.S. I set deflicker from -4EV to -1EV, and the photo became brighter(but I haven't tested it for a long time yet).
So the initial settings(-4EV) needs to be changed in some condition?
Or the AETTR need to be brighter in order to compensate the -4EV?

Valox

Hey,

Is anyone using ettr & deflicker + Lrtimelapse?

In Lightroom everything goes ok. Lightroom read sidecar Xmp data but when i go to Lrtimelapse that sidecar xml data is missing.
I think problem is that Lrtimelapse reads only cr2 files embedded data. I tried every kind of way to get that sidecar data embedded to cr2 file.

Is there any way to move that deflicker xmp data to cr2 files that Lrtimelapse can read it?

dmilligan

No, but I see no reason to use both. Even if LrTimelapse could read the exposure value, what would it do with it? Wouldn't it just ignore it and overwrite it anyway with it's own value?

Valox

I think ML deflicker makes better output than Lrtimelapse. Reason why i want to take pictures to Lrtimelapse is thats quite good tool for "animating" white balance etc. with keyframes. Any suggestion for similar post production what Lrtimelapset can do?

If pictures are already deflickered there's no need to use Lrtimelapse own deflicker. ..And anyway it doesn't (hopeful) make any chances when pictures are ready deflickered.

keepersdungeon

Quote from: Valox on September 15, 2015, 03:09:20 PM
I think ML deflicker makes better output than Lrtimelapse. Reason why i want to take pictures to Lrtimelapse is thats quite good tool for "animating" white balance etc. with keyframes. Any suggestion for similar post production what Lrtimelapset can do?

If pictures are already deflickered there's no need to use Lrtimelapse own deflicker. ..And anyway it doesn't (hopeful) make any chances when pictures are ready deflickered.
After de flickering in lightroom and importing them in LRTimelapse, just un-check the exposure 2012 and use it as u always do, and skip the deflicker phase.

dreamingof8a

Is there a way to limit ETTR to only change exposure in one direction similar to the former bulb ramping function? When shooting a day-to-night timelapse, I usually never want the exposure to go down but only up. Would be great to have an option lke this, ideally with "turn-around" times so yould for example shoot an unattended day-to-night-to-day timelapse and tell ETTR to only keep or increase exposure until a certain time, eg 1am, and then only keep or decrease exposure.