Aperture and DNG - error in the capture date

[edward_brogan]

Hello All,

After some time following the workflow and principles of the DAM book — Nikon Nefs to bridge-acr, convert to DNG to iView/EM — I decided to give Aperture a try.

I have also tried Lightroom. I feel that while Lightroom and the ACR-Bridge to iView combination is a more solid and proper way to go for DAM principles and also for conversion quality, for me, as a somewhat advanced hobbiest but not a professional, Aperture more closely fits my needs.

I have become the official photographer for family and friends events as well as photographing just for my own enjoyment. I now often use, the iLife suite to set up web pages, web galleries, newsletters, home movies and slideshows. I know it may sound juvenile but the iLife and iWork suite are great for me to do things that would otherwise be a bit more difficult, expensive and require more knowledge about web and other applications. In the current situation I have to import my images into iPhoto to make this all work more smoothly. Then I started to think Aperture would be a good way to go. This wasn't an easy choice and of course I will still follow the bucket principle and hope to keep using the DNG format. I intend to use Aperture in referenced mode only.

Let me quickly say that I almost feel a bit apologetic about trying to switch to Aperture lolol. I have been following this forum since it's inception and I have learned a lot. I really value the opinions and knowledge of all the main contributers especially, Peter Krogh and John Beardsworth. I look forward to reading John's blog and I have followed his reporting on Lightroom and Aperture.   I realize he favors Lightroom and I understand why, so it is a little tough for me, but I still think for my use, Aperture would be beneficial. Of course I still can use ACR and Photoshop CS3 for images I deem exceptional. I do have to face the fact that I really don't end up adjusting many of my images to a great degree and as of yet, my dream of having many of them hanging on my walls has not materialized.

That being said, imagine my joy at discovering that my imported DNGs showed their keywords, but my shock to see that the capture or "image time" was incorrect. The dates were correct from what I could see, but the hour was wrong, even though the minutes and seconds were correct. I checked in Bridge, in Bridge the date and time of the Dngs were correct as compared to the original Nefs. I also imported some Nefs into Aperture and all the info was correct when compared to Bridge. It was just when the Dngs were imported into Aperture that the was a time error. I did this with the referenced import, not importing into the Aperture library, but I am sure it wouldn't make a difference.

I do see that there may be some advantages in using the Nefs instead of the Dngs in Aperture but I want to stay with Dng if I can. I don't know if John Beardsworth is testing Aperture with only Dngs or has compared Aperture's performance with both Nef and Dng.

I have created my DNGs with the embedded raw option just in case I need to go back to Nef or use them for a specific task, although it would be really undesirable to extract all 10,000!!! (I know a small amount of images compared to many people on the forum)  The truth is that I haven't been to diligent with my keywording and metadata. My earlier images are all scanned jpgs and are all pretty much keyworded, but only a small percentage of my Dngs have keywords.

If anyone knows whether this is a bug or a shortcoming of Apertures handling of Dngs or an isolated problem I would be appreciative. Any comments or suggestions also are welcome. I am sorry I have been so long winded!

My set-up consists of a Mac G5 dual 2.7 (Mac Pro hopefully in another year) 4 gb ram running 10.5.4, latest Dng convertor used on Nikon D200 and D70 raw files. Aperture 2.1,  Ps CS3 and Bridge/ACR latest versions.

Thanks
Ed Brogan

[johnbeardy]

Ed

Don't be apologetic - hopefully my diatribes mean you make your own decision without the sort of blinkered enthusiasm that some people have for all things Apple.

As for this timing issue, is it showing GMT rather than daylight saving time? 

John

[edward_brogan]

Thanks John,

Actually I find your critiques very informative. You give an honest assessment of the positives and negatives. I do try to choose things by learning some facts and try not to pay attention to the hype (which is difficult if it's hype I like) or to jump in too quickly. Although it seems harder and harder to get good info sometimes. Believe me, on many of the topics you write we would find ourselves in agreement.

Ok, after noodling about I do tend to believe this is most likely a failure in Apples Dng interpretation because the time shift occurs in iPhoto as well as Aperture. Upon importing an Nef and a Dng of that Nef, there is a difference in the time shown between the two.

In the Aperture import screen, when I choose a folder of images and then I select one image, before I hit import it will show some image info at the top right of the panel. There it shows the date and time and time zone. If I choose an Nef I see the correct time and date - verified as the same in Bridge - and an abbreviation for the supposed time zone. With the Dng version of the same file, it shows same date, different hour, same minute and same time zone, while in Bridge it the Dng shows same date and time as the Nef it was converted from.

The time zone that is showing for my files is EDT - Eastern US. Strangely enough, just out of curiosity I checked some Nef files I shot in Hawaii, I know I set the proper Time zone in the camera, but Aperture still showed EDP although the time was correct for where I took the images.  Once the files are imported there isn't any reference in any of the metadata panels for exif that shows the time zone or a selection for daylight savings. Nor could I find anywhere in the Bridge file info panel referring to either a time zone or daylight savings time.

In the Aperture import panel there is a way to alter the time on import, but being I don't know what the effect would be on an export I doubt it is a good idea to alter that info. I guess I could do a test set, then export to see the resulting file times. 

Thanks for any info on this, just curious if you are able to observe the same behavior

Ed

[johnbeardy]

Ed

Yes, I did look at one or two recent pictures before making my earlier reply. Knowing exactly when I'd taken them, I could quickly confirm Aperture was showing the DNGs' Image Date incorrectly by one hour.

It seems to be consistent too. I've just imported a new NEF and its corresponding DNG into Aperture - the NEF shows the correct summer time while the DNG is one hour out. I also looked at a pair of files shot before the clocks went whichever way they went in spring - Aperture shows identical times for the two files. So it seems to be a problem with summer time (which LR doesn't have - no errors observed).

To correct it, it looks like you have to change those Time Adjustment settings. I chose GMT as the Actual Time Zone, which worked (but living 2 miles west of the Greenwich Meridian may make this easier for me). One downside is that you have to revisit this setting each time you import DNGs.

Incidentally, I find no difference processing NEFs or the DNGs made from them. That's what I would expect, as Aperture will detect the DNG was from a Nikon format and process accordingly. There might be a difference if one applied the generic DNG profile which is designed for unsupported cameras. The big advantage of DNG, as you've found, is that Aperture 2 reads any embedded metadata - I'm amazed it still fails to read anything in sidecars.

John

[edward_brogan]

John,

I did a little experimenting today. First to the time issue…

During daylight savings my DNGs are 9 hours behind the correct time displayed by the NEFs. During non daylight savings time the DNGs are 10 hours behind the correct time. In the last year I have traveled to Hawaii and Arizona. I know I changed the time zone in the D200 preferences for Hawaii and I think I forgot in Arizona but either way NEF or DNG show eastern standard time as the camera setting on import, so I am guessing that particular function probably doesn't work. One odd thing is that, whether it is a 9 or 10 hour difference, if I apply the GMT+5 as the Actual Time Zone to the DNGs on import, it gives it the correct time.

Just to see what would happen to the file times upon exporting from Aperture —

If I export masters from DNGs that have not been time corrected with the embed metadata enabled, I get DNGs with the correct time displayed in Bridge. If I export versions from the same DNGs I get tiffs or whatever file with the wrong time displayed in Bridge.

If I export masters from DNGs that have been time corrected with the embed metadata enabled, I get DNGs with the correct time, if I export versions from those DNGs I get files that show the correct time in Bridge.

It appears that Aperture doesn't alter the master file's EXIF data, but only adds IPTC on export, but for versions I am guessing it makes a completely new file.

Since I was skulking around the metadata panel I observed the following differences —

The following metadata fields show no information for a DNG, but do show info when an NEF is selected:

Flash exposure compensation
Lens minimum mm
Lens maximum mm
Nikon white balance
Nikon sharpen mode
Nikon Quality - (for NEF it shows Raw)
Nikon Focus Mode
Nikon Flash Setting
and under Lens Model for the NEF it shows 
AF-S DX Zoom Nikkor 18-70mm f/3.5-4.5G IF-ED   or
Sigma 10-20mm F4-5.6 EX DC HSM
for DNG it shows    18-70 mm f/3.5-4.5   or     10.0-20.0 mm f/4.0-5.6

next to the caption Software for the NEF it is Ver.2.00 and the DNG shows Ver.1.02  but…
last Novembers images that I just got around to converting to DNG shows the same software for both DNG and NEF which was Ver.2.00
additionally there is a caption EXIF Version which shows 2.2.1 only when a DNG is selected.

Further investigating for any info about Apples DNG implementation led me to this webpage on Apples site —

 http://docs.info.apple.com/article.html?artnum=307385

That article mentions the Auto Noise Compensation adjustment under Raw Fine Tuning is not available with DNG images. Actually whether it was a DNG or NEF the Auto Noise Compensation selection box was available to either make active or to make inactive for me. I don't know what value that feature has in the Raw conversion but it does work.

I guess Apple doesn't know that feature works on the NEF converted to DNGs. lololol

Really, I think the best situation would be if Nikon themselves supported the DNG format which is probably not very likely. I have never used or even have seen a Capture NX raw conversion and I am just curious if having access to all the info in the NEF file makes any difference.

Either way, since I can adjust the time I will stick with DNGs. I agree with you about how amazing it is that Aperture doesn't read the sidecars.

Ed

[edward_brogan]

The Apple support Web site search function was down the last couple of days, so when it came back up I found a couple references to the DNG time code problem.

Here is one thread:

 http://discussions.apple.com/thread.jspa?messageID=7143643&#7143643

One contributer theorized:

ifarlow wrote:

"I am guessing here, but what you see sounds like what I experienced. What I found is that when images are converted to DNG, the DNG date/time data is edited to GMT plus an offset, which the Mac OS X (and therefore Aperture) doesn't seem to read. I have posted about this until I am sick of posting any more (on Adobe's forums), and although Adobe suggests that a fix is forthcoming, this has been an issue for over a year now.

So, for example, I have a CR2 file that shows a date/time of 05-05-2008 22:05:30. When I convert this to DNG, the date/time becomes 05-05-2008 12:05:30 +5 (or something like that). So, OS X (and Aperture) see the date/time as 05-05-2008 12:05:30, while Lightroom/Photoshop sees the date/time as 05-05-2008 22:05:30.

A pain in the rear end, if you ask me, and the reason I refuse to use DNG from this point forward, even if Adobe says they have taken care of this issue. My chief complaint is that I see no need to adjust the date/time of my image to GMT, and since I didn't specifically ask for it, it shouldn't have happened. Now, I have to jump through hoops to get my DNG files into Aperture with the correct date/time.

Message was edited by: ifarlow"


Any way that is one theory, I still believe it is Apple who bears the responsibility to read the DNG file correctly.

Ed