Magic Lantern Forum

Using Magic Lantern => Raw Video => Topic started by: mvejerslev on July 09, 2013, 03:02:56 PM

Title: No EXIF!!
Post by: mvejerslev on July 09, 2013, 03:02:56 PM
I'm having the recurring problem of no, or incomplete EXIF data in my DNGs. It holds no camera information, no ISO information, no lens information, no setting information etc. This is the build from 7-7, used with latest Raw2DNG.

What am I doing wrong? What can I do to prevent this in the future? Everything shot without EXIF information is absolutely worthless, since the Raw developer needs it to do its magic...
Title: Re: No EXIF!!
Post by: 1% on July 09, 2013, 06:29:29 PM
Not implemented yet.
Title: Re: No EXIF!!
Post by: mvejerslev on July 10, 2013, 12:53:32 AM
Huh? I've had exif in most all of my raw footage so far, except one earlier build. Now its gone again. I cannot. I stress. I cannot develop the DNGs without the EXIF! The raw developer doesnt know which camera, ISO speed etc it is! It looks like crap...
Title: Re: No EXIF!!
Post by: a1ex on July 10, 2013, 12:57:59 AM
Post a DNG with exif and one without.

And also something that looks like crap because the raw developer didn't know the ISO. Then, set ISO with exiftool and show the improvement.
Title: Re: No EXIF!!
Post by: mvejerslev on July 10, 2013, 01:46:25 AM
No problem - how do I post DNG's do you have a preferred upload site, or is it possible to embed attachments?

I'm maybe willing to eat my words on the 'always had exif' thing, but here's a quick comparison where I entered the correct ISO into a DNG via Exiftool:

https://plus.google.com/u/0/photos/102516342678541815125/albums/5898773988033658657/5898773988557612882?pid=5898773988557612882&oid=102516342678541815125&authkey=CIfd6p7T0KbiDQ (download or go full screen to inspect).
Title: Re: No EXIF!!
Post by: a1ex on July 10, 2013, 08:35:44 AM
It's on the todo list, but it will take a while. It requires redesigning the raw file format.
Title: Re: No EXIF!!
Post by: mvejerslev on July 10, 2013, 01:07:09 PM
Hm ok. The exiftool route is very cumbersome. The thing is, Camera Raw has a database of noise profiles for various cameras. It needs the camera make and model for color profiles, but also the ISO speed for noise profiling etc.

I hope this demonstration kicked it up a bit on the priority list, as the difference is very big.

Thank you for all the hard work so far :-)
Title: Re: No EXIF!!
Post by: eyeland on July 10, 2013, 07:23:11 PM
Quote from: a1ex on July 10, 2013, 08:35:44 AM
It's on the todo list, but it will take a while. It requires redesigning the raw file format.
How about a temporary solution where the relevant camera settings are saved to an xml for each clip. Exif could then be imported from the xml using EXIFtool (or this step could be implemented in one of the batch apps)? Or is this a waste of time if real Exif data is in the pipeline?
Title: Re: No EXIF!!
Post by: spider on July 23, 2013, 01:25:48 AM
Quote from: mvejerslev on July 10, 2013, 01:46:25 AM

I'm maybe willing to eat my words on the 'always had exif' thing, but here's a quick comparison where I entered the correct ISO into a DNG via Exiftool:

Which values did you exactly change? I think there is more than one value for the camera model.
Title: Re: No EXIF!!
Post by: Muf on July 23, 2013, 03:53:01 AM
I think the easiest workflow to be implemented as a stopgap would be to shoot a JPG or CR2 before recording, and have the RAW to DNG converter receive an optional filename argument for a JPG or CR2 file to copy the EXIF from. Since you're shooting with the same lens, same zoom, same iso, the EXIF should mostly match up with the relevant settings/parameters for the RAW video.
Title: Re: No EXIF!!
Post by: bnvm on July 24, 2013, 12:21:34 AM
The best way now is to just shoot off a jpg right before you do your raw recording, next use exiftoolgui to transfer the exif data from the jpg to the dng's once extracted. It is pretty simple start the gui, navigate to and select all the dng's to update. In the menu select update exif from single file (may not be the exact menu title but close), then just select the jpg. You will have dng's with proper exif. Its not a bad work around until it is implemented directly in the raw file.
Title: Re: No EXIF!!
Post by: mvejerslev on July 24, 2013, 04:01:18 AM
QuoteWhich values did you exactly change?

I'm not getting into exact tags. I'd go with what Muf and bnvm said.
Title: Re: No EXIF!!
Post by: eyeland on July 24, 2013, 04:09:36 PM
I have been trying to get one of the batch tool devs to look at this issue, but atm it would seem that they are busy doing other things. As I have suggested in several threads, it should be relatively straight forward to to import EXIF during RAW2DNG conversion from an xml saved in-camera.
I was surprised at how little attention this issue got, but seeing as Mvejerslev was one of the only ppl to respond to posts/threads dealing with this, a month ago I gave up waiting/pushing and since then I have been content with importing from a still. I am very interested in finding out exactly which tags are used by ACR, only thing I am sure of so far is that it needs "makernotes" for camera calibration profiles to work.

@Mvejerslev Have you done any extensive testing in regards to noise with and without exif?
I have not been able to replicate the rather drastic differences that you show above.
EDIT: I oly now realized that your test was made using version 2012. I use 2010 to avoid flickering, maybe 2012 uses EXIF more "intelligently"?
EDIT2: Edited to sound less impatient :)
Title: Re: No EXIF!!
Post by: bnvm on July 24, 2013, 05:38:50 PM
Quote from: eyeland on July 24, 2013, 04:09:36 PM
I have been trying to get one of the batch tool devs to look at this issue, but atm it would seem that they are busy doing other things.. I don't really get it though. As I have suggested in several threads, it should be relatively straight forward to to import EXIF during RAW2DNG conversion from an xml saved in-camera.
I am baffled at how little attention this issue gets, but seeing as Mvejerslev was one of the only ppl to respond to posts/threads dealing with this, a month ago I gave up waiting/pushing and since then I have been content with importing from a still. I am very interested in finding out exactly which tags are used by ACR, only thing I am sure of so far is that it needs "makernotes" for camera calibration profiles to work.

@Mvejerslev Have you done any extensive testing in regards to noise with and without exif?
I have not been able to replicate the rather drastic differences that you show above.
EDIT: I oly now realized that your test was made using version 2012. I use 2010 to avoid flickering, maybe 2012 uses EXIF more "intelligently"?

I think they are busy with other stuff at the moment, dual iso seems to be a hot topic at the moment. Also since they are planning on implimenting it eventually with the updated raw format I imagine they don't want to spend valuable time developing a temporary solution when there are already some easy work arounds  that work just fine.
Title: Re: No EXIF!!
Post by: mvejerslev on July 24, 2013, 11:49:12 PM
Eyeland, use high ISO and 3x crop mode. You should see a quite drastic difference from setting correct ISO exif value vs none. Also, make sure you are actually using the denoise sliders to put CR to work. And the 2012 version has much better denoising than 2010.
Title: Re: No EXIF!!
Post by: mvejerslev on July 24, 2013, 11:51:30 PM
Quoteeasy work arounds  that work just fine

But its not really an easy work around for most people, not least for people not aware, and having RAW footage with lots of noise to battle with in post actually negates having the data available for a real RAW developer to iron it out (with proper exif). Raw is just that. Raw. It really needs the exif container.
Title: Re: No EXIF!!
Post by: eyeland on July 27, 2013, 04:06:00 PM
I totally understand that the devs try to focus on whatever is more important/sensible to work on. With my limited knowledge of programming I am unable to determine the workload involved in the integration of ExifTool import, it just seemed so simple :)