Magic Lantern Forum

Using Magic Lantern => General Help Q&A => Topic started by: mSpider on June 27, 2013, 12:08:39 PM

Title: How can I use the XMP deflicker files?
Post by: mSpider on June 27, 2013, 12:08:39 PM
Found the steps to use the UFRAW, but I wnat to use XMP files.
Anyone know where I might find instructions?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 27, 2013, 01:24:02 PM
You place the xmp files in the same folder as your dngs, open the dng,s in lightroom or photoshop. Xmp-settings should apply automatically. More info here
http://www.magiclantern.fm/forum/index.php?topic=5705.msg41478#msg41478
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 27, 2013, 02:03:09 PM
I'm using CR2's
Same deal?
And I don't have to selct all the photos and choose "Read metadata from file"?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 27, 2013, 02:17:07 PM
I think it,s the same with cr2, havn,t tried that though.
Good luck
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 27, 2013, 02:31:16 PM
Do you use Adobe Lightroom?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 27, 2013, 02:41:43 PM
yes
Title: Re: How can I use the XMP deflicker files?
Post by: Audionut on June 27, 2013, 02:52:13 PM
If you import in LR from the card, I don't think it copies the xmp's.

Copy all the files manually into a folder on your hdd and import to your catalog from there.  It will read the xmp and automatically apply the exposure adjustment.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 27, 2013, 04:12:56 PM
Thank you.
I tried to test it this morning, but I closed the flip out LCD on my 60D.
It doesn't make XMP's with the LCD screen closed......
I thought maybe you had to "Read Metadata from File"...but you say no....
Title: Re: How can I use the XMP deflicker files?
Post by: Audionut on June 28, 2013, 03:04:37 AM
It needs to be able to access the quick image review on the LCD.

You can fold that LCD around on a 60D so that it looks like a regular LCD correct?

Then go to image review settings in Canon menu and adjust to taste.  ML only needs the minimum 2 secs. 
I personally often have it set to "hold", so that I can review the image with raw based histogram/zebras.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 28, 2013, 08:17:35 AM
Hi Audionut, thank you for your replies...
I do timelapses, so I don't need to review each picture--but I understand that ML needs to be able to.
I just did a sunset timelapse, with the deflicker XMP's turned on.
I put the XMP's in the same folder as the CR2's, and imported the folder to Lightroom 4.2:
No deflickering happening.
I then tried the "Read metadata from file" option.
Still no deflickering.
Any ideas?
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 28, 2013, 08:33:28 AM
I just checked the time on my 60D:
Its about a minute ahead of my computer.....
Could this be the problem?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 28, 2013, 10:03:44 AM
I have my camera set an hour later than my computer. I also synchronise my folder together with the xmp,s, like audionut suggests. I never import straight to lightroom via camera.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 28, 2013, 02:06:21 PM
So there is more to it than just copying the XMP files to the folder with the pictures--that ISN'T the only step.
I must somehow "synchronize" my XMP's.....

Do you know where I might find instructions on how to "synchronize my XMP's to my folder like Audionut suggests?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 28, 2013, 06:16:01 PM
Well, start with importing a folder to lightroom by making the folder than choose import. Name it xmp,movies or something. Once imported start loading your files and xmp,s in this folder. You fill the folder outside lightroom. Within lightroom right click on the folder, choose synchronize. Done
Title: Re: How can I use the XMP deflicker files?
Post by: Audionut on June 28, 2013, 06:21:00 PM
I copy all my CR2 and XMP files to a folder on the HDD.  So select all the files from the card drive and copy to folder on HDD.

Then import that folder in LR.  It should automatically apply the exposure adjustments.  If it doesn't, something is wrong in your process.

Make sure you are using sRGB color space in the Canon settings. 

Check the file names of your files.  You should have for instance,

D46A0001.CR2
D46A0001.XMP

edit:  Only new to LR, previous ACR user.  Danne's process to synchronize the folder sounds better.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 29, 2013, 01:25:22 PM
How do you "synchronize" the folder?
My "process" didn't work--no deflickering going on.
As far as I can tell, no XMP data being uploaded to photos.
Title: Re: How can I use the XMP deflicker files?
Post by: glubber on June 29, 2013, 02:26:52 PM
I'm just processing my first timelapse with XMPs and had no issues:
- copying files from sd to hdd
- Inside LR importing folder from hdd, grid-view (G), selecting all the images (Ctrl-A) of folder
- Select Metadata menue -> Read metadata from files.
- wait a while .... et voila
- exporting to jpg etc... (wait a very long time)  :P

not as fast as ufraw.... but at least no pink highlights.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 29, 2013, 04:44:16 PM
Got it--so its not enough to just put the XMP's in the same folder--you have to have LR4 "Read Metadata From File"...
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 29, 2013, 08:16:49 PM
I simply synchronize my folder with all the files, works for me.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on June 30, 2013, 12:27:39 PM
What do you mean "synchronize my folder with all the files"?
How do you "synchronize"?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on June 30, 2013, 04:14:26 PM
"Well, start with importing a folder to lightroom by making the folder than choose import. Name it xmp,movies or something. Once imported start loading your files and xmp,s in this folder. You fill the folder outside lightroom. Within lightroom right click on the folder, choose synchronize. Done"

http://livedocs.adobe.com/en_US/Lightroom/1.0/help.html?content=WS0E8634AC-5DB4-4d0c-9CF5-840A1BC95FA0.html
http://www.image-space.com/Lightroom_Tips_Tricks/Library_Module_Tips/Synchronize_Folders/Synchronize_Folders.html
http://www.texaschicksblogsandpics.com/lightroom-tutorial-synchronize-photos-vs-import/
http://www.youtube.com/watch?v=gIvQrfxqWeo

Synchronizing is one of the most basic functions in lightroom. Tried to explain so many time already. My text plus four links on the topic. If this doesn,t come through I don,t know what will.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on July 01, 2013, 06:55:48 AM
I will check those.
Thank you.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on July 01, 2013, 06:57:53 AM
Thanks for the links.
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on July 01, 2013, 04:52:40 PM
Still not working.
Can you tell me, are there Develope Settings applied in lightroom if this is working?
Do you get the little icon that has a "+/-" on it in the lower corner of the thuumbnails?
How can I see if LR has successfully detected the XMP files the Magic Lantern creates?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on July 01, 2013, 07:44:44 PM
You get the +- icon, that,s how it works. It,s supposed to level your exposures the same so no flicker will appear.
Try without the xmp files and synchronize, then you se the +- icons dissapear
Title: Re: How can I use the XMP deflicker files?
Post by: mSpider on July 02, 2013, 05:09:39 AM
No, Im not getting the "+/-" icon--the CMP files are not working for me-
The XMP files are not association with the photos in any way.
Its like they don't even exist.
Its not working for me.
But when it does work properly, which develop settings are changed?
Just exposure--or are others like highlights changed as well?
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on July 02, 2013, 07:31:52 AM
I think it was the exposure slider only. I used the silent picture mode with dng,s. I also had my camera clock set one hour later than my computer.
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on July 02, 2013, 10:39:32 AM
Camera 13:00, computer 14:00. One hour betweenrelation just to be clear
Title: Re: How can I use the XMP deflicker files?
Post by: Audionut on July 02, 2013, 11:28:25 AM
Quote from: Danne on July 02, 2013, 10:39:32 AM
Camera 13:00, computer 14:00. One hour betweenrelation just to be clear

Is that to make sure the XMP's get read?

Is so, that was fixed here (https://bitbucket.org/hudson/magic-lantern/commits/58925dbdcbe93592ab1e5eacf5b6c4416d995506).
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on July 02, 2013, 01:06:45 PM
Probably fixed, I just don,t bother to change the time on my camera. Just shared whatever settings I used when doing my timelapse sequence for mspider. works good :)
Title: Re: How can I use the XMP deflicker files?
Post by: ColinWarhurst on September 26, 2013, 01:03:35 AM
Hi all - As ever, brilliant work all round; really excited and trying to get stuck into ETTR timelapse.

However, I too am struggling to the .XMP files to do, well, anything to a batch of images. I was wondering;

- Is Lightroom a pre-requisite, or is there a way to do import a sequence and have it de-flicker using just After Affects? Or even just ACR?

- If After Affects or ACR alone is an option, how do I get de-flickering (getting each CR2 to read it's XMP highlight data I assume?) across a batch?
In Adobe Camera Raw (ACR) I don't see any automation or de-flicker options; the closest thing I can find is an "auto" exposure for raws, but that only seems to apply an auto setting on a per-image basis.

I beleive I have followed the camera settings correctly, but with XMP settings. This is because I am on a Mac (as opposed to the UFRAW workflow for PC users?) but all the guides for XMP seem to... stop. :-(
A step-by-step (or video?) by anyone who has this working in XMP, on OSX, would be massively appreciated!

Many thanks, apologies if I'm missing anything super obvious.
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 26, 2013, 02:28:36 AM
Flicker Free ETTR Timelapse: - -Beginners Guide & Basic Post Processing --
http://www.magiclantern.fm/forum/index.php?topic=5705.0

ACR or UFRAW is prerequisite to open the cr2 files, the exposure of each file is adjusted by the setting contained in XMP.

The workflow is in the tutorial.  I use PC but some others use OSX
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on September 26, 2013, 02:29:18 AM
i use mac, i can tell u what i know, 2mins n ill add to this.
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on September 26, 2013, 02:36:32 AM
Mac.

Deflicker is now added to the .cr2 its self so you wont see an xmp, sometimes the terminal code for adjust batch exposure and setting them all the same dosnt need to see the xmps sometimes it does, if it does not find xmp's, open all the cr2 images, select all and press auto white balance and then back to current, this will create an xmp for the images.

you need exiftool installed on your mac, google search will take you there. its a terminal command.

ML:
Deflicker - .xmp

On mac put all your images and xmps in one folder.
open up terminal, enter this, exiftool -Exposure2012+=+*.** /drag folder here containing cr2's and .xmp's

Where the *.** is enter the amount you want to set, eg 0.05, next to the number you have chosen, too the left is +, +=over expose for under add -

hope this makes sense and helps.
Title: Re: How can I use the XMP deflicker files?
Post by: ColinWarhurst on September 28, 2013, 03:35:05 PM
Doyle; many thanks, your tutorial worked a treat.

Haven't quite worked 'how' it has worked, but I seem to have ended up with some additional XMP files with the suffix 'original' at the end of them. Perhaps Exiftool is being friendly and making backups of the originals?  :P

To clarify (if anyone else is having the same issues) this was my process;

1 - Download and install exiftool FOR MAC (There is a specific Mac OSX package)
2 - Prepare/move CR2 files and .xmp files from Magic Lantern in one folder
3 - Open Terminal
3 - Enter the coomand as Doyle explained above;

exiftool -Exposure2012+=+*.** /drag folder here containing cr2's and .xmp's


Where the *.** is enter the amount you want to set
eg 0.05, next to the number you have chosen
Too the left is +
+=over expose
-= under exposure

4 - Allow process to run (New/backup XMP files were created for me. I waited until the list had finished)
5 - Select all CR2 files, open in Adobe Camera Raw
6 - FILES SHOULD OPEN, DE-FLICKERED
7 - Select all, make White Balance auto. (Unsure about next bit?...)
Make any edits should you want them? Note, that if you change exposure now, you'll undo the de-flickering!
(Perhaps edits should be done first, then you start the de-flickering command afterwards? Needs testing!)
8 - Close Adobe Camera Raw
9 - In After Affects, import the first CR2 image, select 'Camera Raw Sequence.' Create timelpase!

Many thanks Doyle! Maybe this Mac step by step should be added to that top post/tutorial thread?
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 28, 2013, 03:50:46 PM
Quote from: ColinWarhurst on September 28, 2013, 03:35:05 PM
Many thanks Doyle! Maybe this Mac step by step should be added to that top post/tutorial thread?
DONE!  Thanks to all!!!
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on September 29, 2013, 12:57:06 PM
yeah sorry about the make edits, DO NOT TOUCH EXPOSURE!! you are correct on that one :), also, be careful tweaking highlights etc this can produce flicker in the highlights, i use an adjustment layer in after effects for that :) - Must use dng's for best quality.

Glad this worked for you man!
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on September 29, 2013, 01:03:54 PM
i noticed you mention other XMP's,

There your backups of the original man, if everything fails, delete .xmp's and rename .xmp_orginal back to xmp
Title: Re: How can I use the XMP deflicker files?
Post by: saltador on September 29, 2013, 01:30:41 PM
Where the *.** is enter the amount you want to set
eg 0.05, next to the number you have chosen
Too the left is +
+=over expose
-= under exposure

I still have a doubt here...please forgive myself..maybe will make it even more clear...

if my images are overexpose by 1 EV i need to type this in the terminal..(mac)

exiftool -Exposure2012+=+1.00 /Users/Alaptop/desktop/folder

if my images are underexpose by 1 EV i need to type this...

exiftool -Exposure2012+=-1.00 /Users/Alaptop/desktop/folder

if this is right please let me know..
I also got the xml-original one time..should i copy them to a different folder or keep them there..
still doing tests..sorry for asking a lot.

so, i read that if i change exposure values in lightroom i lose all the deflickering from ML..right?
but i could change any other value and keep deflickering right?

thank youuuu.

Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 29, 2013, 01:48:49 PM
Quote from: saltador on September 29, 2013, 01:30:41 PM

if my images are overexpose by 1 EV i need to type this in the terminal..(mac)

exiftool -Exposure2012+=+1.00 /Users/Alaptop/desktop/folder

No, if you images are overexposed you need to decrease the exposure:
exiftool -Exposure2012+=-1.00 /Users/Alaptop/desktop/folder

Quote from: saltador on September 29, 2013, 01:30:41 PM
I also got the xml-original one time..should i copy them to a different folder or keep them there..

keep the originals and do more testing to answer your own questions like the one obove

Quote from: saltador on September 29, 2013, 01:30:41 PM
so, i read that if i change exposure values in lightroom i lose all the deflickering from ML..right?
but i could change any other value and keep deflickering right?

Do not touch exposure directly in lightroom or on any program.  You can use exiftool to change the entire files by the same amount, up or down.

You should be able to change other values as long as the changes are global (for all of the files by the same amount).
Title: Re: How can I use the XMP deflicker files?
Post by: saltador on September 29, 2013, 02:14:05 PM
Renato...you are the best.

I'm at this great apartment with some amazing view for 1 more week and i wanted to get as many time lapse as possible while am here.
as..right now i got up early to do another night to day...since the day before didn't work...hehehe..that's my rush to learn as much as possible and i read too fast and miss somethings..sorry and thank youuu.

now i understand clear..the exirtool command..thank you.

maybe you might know this...I'm trying to understand what auto ETTL does..

I finished a night to day timelapse on my 5dii...

started at f-2.8, shutter 1/6, iso 1600

it seem to change iso and shutter but the f-stop was always 2.8

is this always like this? does auto ETTL adjust f-stop at all?

another day reading and reading tol earn more..thanks to all of you.
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 29, 2013, 02:30:14 PM
Quote from: saltador on September 29, 2013, 02:14:05 PM
it seem to change iso and shutter but the f-stop was always 2.8
is this always like this? does auto ETTL adjust f-stop at all?

ETTR does not touch f-stop.
If you want to change f-stop try this new develpment:
Intervalometer Ramping Module (adv_int.mo)
http://www.magiclantern.fm/forum/index.php?topic=8431.0
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on September 29, 2013, 03:24:41 PM
As RenatoPhoto said, if you are over you under expose, if yo are under you over expose, what the command line is doing is setting all images to same exposure, you will see they are all different in ACR but they all match :) thats the purpose of the command.
Title: Re: How can I use the XMP deflicker files?
Post by: saltador on September 29, 2013, 04:12:59 PM
thanks Renato and Doyle..

I get it now...ETTL does not change f-stop...and exiftool..changes exposure to all them...


I imported to lightroom without going thru exiftool...and i got a constant change of exposure..almost every other frame has a different exposure value.. one frame exposure 0.00 next frame exposure... -1.2  for example..and it seems to be constant the out..

any ideas...

I'm about to give up and this and find other method or forget timelapse at all...hehehe.

thanks for all your help...

i know there was a new development with ramping but i'm hesitand to try since its taking me so long to get anything working..
I'm jelous of the people who are taking advantage of this wonderful developments..

THANK YOU for all your help.
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 29, 2013, 04:47:08 PM
Quote from: saltador on September 29, 2013, 04:12:59 PM
I imported to lightroom without going thru exiftool...and i got a constant change of exposure..almost every other frame has a different exposure value.. one frame exposure 0.00 next frame exposure... -1.2  for example..and it seems to be constant the out..

Deflickering is doing the job if you see the exposure jumping.  Just generate the video and you will see the results, Flicker Free.
Title: Re: How can I use the XMP deflicker files?
Post by: saltador on September 29, 2013, 09:14:40 PM
I'm sorry Renato..but i'm back..hehehe.

I exported and as i thought the flickering is extreme....when i goes from exposure 0.00 to -1.2 is a big change..big changes in light exposure..

I imported into Lightroom (without passing thru exiftool) exported all as jpg..imported image sequence in QT7 and exported profess 422..just to test...

i have no idea what i could be doing wrong... :-\

thanks for all your help thou.

you all are the best.
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on September 29, 2013, 09:33:57 PM
What camera are you using, what build.
Post the intervalometer settings
Post the Post Deflicker settings
Post your Auto ETTR settings....

My crystal ball is down today...
Title: Re: How can I use the XMP deflicker files?
Post by: saltador on September 30, 2013, 03:35:34 AM
sorry...

Canon 5dii
build...27 sept i believe..

photo Raw
image review 8sec
WB 4000


ML
auto ETTR Always on
slowest shutter 1'6
rest as stander

Pos deflicker on
adobe XMP
percentile 50%
target -4EV

Intrevalometer 5sec
start after 10 sec
stop off
focus ramp off

that's all..



PS: I think i got all settings right...so..my mind thinks maybe i'm doing the highly build update wrong..maybe missing something there.
just thinking... I try dropping the new build and replacing the one i had but i used to get an error message like..missing fonts..so now i replace everything but the fonts.DAT in the data folder...don't know..of course i replace the autoexec.bin..maybe this is not it..weird. oh well. right now trying the latest build with the av ramp..maybe i get lucky here..thanks a lot anyways.
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on October 01, 2013, 11:13:56 PM
exiftool with make exposures match... think you are missing that part out, so if one is 0.00 and another is +1.2, exiftool will make these flicker free...

Also try percentile at 75%
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on October 01, 2013, 11:24:33 PM
Quote from: saltador on September 30, 2013, 03:35:34 AM
image review 8sec

slowest shutter 1'6

Intrevalometer 5sec

your image review is longer then intervalomenter?
Try image review 2 sec
Or intervalometer 15 sec

What is Slowest Shuter =1'6  (1 minute 6 seconds?) or do you mean 16 seconds or what

Title: Re: How can I use the XMP deflicker files?
Post by: saltador on October 04, 2013, 02:05:45 AM
thanks so much...

I gave up on test cause i was spending too much time and had other things to take care off.

renato...I...yes..i didn't think about inetrvalometor having to be longer..i fixed it later..and test came similar.
and 1'6 was meant to be slowest shutter speed 1/6...I will try your suggestion ..thanks thou..i willl post a clip as soon as i get one to show. cheers

Doyle..I didn't know i had to go the exiftool to get the deflicker done...i was just importing straight to LR..I thought exiftool was just making each frame a exposure higher or lower..
what setting i should use for exiftool?  exposure -0.05%?
also will try you percentile at 75%
thanks a lot.


One thing i'm still trying to understand and maybe someone have the time to explain...ETTR seems to me to be a bit more inconsistent that if i just set an exposure and ramp the AV, or ISO...am i wrong? in terms of the posibility of ETTR making one frame a bit diferent than the one before..where if the set exposure will render the same exposure.

I'm asuming ETTR and deflicker is the best way to go..bacause i see all smart people talking about it..hehehehe..i guess i just have to get it right. will keep practicing...thanks to all here.
Title: Re: How can I use the XMP deflicker files?
Post by: RenatoPhoto on October 04, 2013, 03:40:14 AM
Quote from: saltador on October 04, 2013, 02:05:45 AM
Doyle..I didn't know i had to go the exiftool to get the deflicker done...i was just importing straight to LR..I thought exiftool was just making each frame a exposure higher or lower..
what setting i should use for exiftool?  exposure -0.05%?
also will try you percentile at 75%

I have doubts about this.  As far as I know exiftool should only be used to bump up or down all the exposures by a a certain amount.  I work on PC and never used this tool to change anything ever!

Quote from: saltador on October 04, 2013, 02:05:45 AM
One thing i'm still trying to understand and maybe someone have the time to explain...ETTR seems to me to be a bit more inconsistent that if i just set an exposure and ramp the AV, or ISO...am i wrong? in terms of the posibility of ETTR making one frame a bit diferent than the one before..where if the set exposure will render the same exposure.

ETTR is a module to expose your images to the right so as to maximize the signal-to-noise ratio, meaning have lower noise in your shadows and probably better color.  ETTR has nothing to do with deflicker, it is just exposing each image to the best of the cameras abilities to try to capture all the details possible.  This module has become more complicated and powerful and now you have better control of what is that you are trying to capture best.  For more information go here: http://www.magiclantern.fm/forum/index.php?topic=5693.0

If the change in exposure from one shot to the next is extreme, then ETTR will be going all over the place trying to adjust to each exposure.  For this reason it could seem that exposure ramp via AV or Auto ISO is smoother.  I have experienced this kind of variation when the interval time  in the intervalometer is very long, ie 2 minutes.  I never use ETTR with and interval time longer then 1 minute.  I had a situation with passing clouds where the exposure was varying quickly and ETTR produced very bad results so a shorter interval time is always better.  In some cases it may be better to use other exposure methods.

ETTR is not an instant perfect photo mode, what I mean is that it can take more than two shots to get the software to converge into an ideal exposure to the right.  So if the exposure changes from one shot to the next then ETTR is in a hunting mode.

Quote from: saltador on October 04, 2013, 02:05:45 AM
I'm asuming ETTR and deflicker is the best way to go..because i see all smart people talking about it..hehehehe..i guess i just have to get it right. will keep practicing...thanks to all here.

Deflicker is another beast all by itself.  I dont know the math behind this but it must assume some kind of average exposure ramp and it adjusts each shot via xmp file so as to bring the exposure of that shot very close to the average exposure ramp.  I assume that this algorithm can also get somewhat screwed if there are a lot of exposure changes from one shot to the next.

Assuming that all is working properly, when you import a cr2 file into ACR or lightroom, it has an exposure adjustment of zero, but when the software reads the xmp file, then the exposure will be adjusted by some amount sufficient to bring the exposure to some predefined standard by the Post Deflicker algorithm.  For example when I open the files in ACR without the xmp files and I walk through the images, it is clear that the exposure is changing from one image to the next.  If I open the same files accompanied by the xmp file, then the exposure change from one image to the other is minimal, and I can see how the exposure slider changes from one image to the next.

Make sure you read carefully the
Flicker Free ETTR Timelapse: - -Beginners Guide & Basic Post Processing --
http://www.magiclantern.fm/forum/index.php?topic=5705.0
Title: Re: How can I use the XMP deflicker files?
Post by: Doyle4 on October 05, 2013, 03:51:47 AM
Exiftool first for sure :)

RenatoPhoto's comment above this one is a very good read, read it.. re read it, use it :) haha. itll come to you eventually, im still learning to get the perfect flicker free.

Also what i learnt not to do was NOT to meter on a building etc, my skys where getting completely different exposures as the building was getting correctly exposed.. lesson learned there for me ;)
Title: Re: How can I use the XMP deflicker files?
Post by: Danne on October 05, 2013, 08:14:32 AM
I, d say the xmp files follows the first exposure in the timelapse and applies all the way to the last. Tried a night to day timelapse which resulted in heavily underexposed daytime shots. Going from day to night gives me overexpoed nighttime shots.
For daytime timelapse xmp deflicker is the best. Maybe even for sunsets and so on but it will need some post software to ramp the exposures.
Title: Re: How can I use the XMP deflicker files?
Post by: classicbs on December 28, 2014, 06:56:04 PM
Hi there I'm trying to use exiftool to reduce exposure on all the photos in a time-lapse sequence

QuoteOn mac put all your images and xmps in one folder.
open up terminal, enter this, exiftool -Exposure2012+=+*.** /drag folder here containing cr2's and .xmp's

Where the *.** is enter the amount you want to set, eg 0.05, next to the number you have chosen, too the left is +, +=over expose for under add -

I tried this but I just get an error saying "no file specified"

Any ideas?  Many thanks