Time stamp on photographs (yes there is a computer question)

risman
New Member

Posts: 42

Time stamp on photographs (yes there is a computer question) Nov 7, 2019 17:33:36 GMT -5

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Post by risman on Nov 7, 2019 17:33:36 GMT -5

Here is a programming challenge for someone. It might not seem like it’s relevant to this forum, but please read to the end.

While on an African safari recently, I was using a Canon 5D Mark IV camera and copying the photos I took each day to my laptop and to an external HD. My camera was set up to capture duplicate images in RAW and JPG (2 photo formats, for the non-photographers out there). I found that the RAW and JPG images were displaying different time stamps (the date and time the photos were taken). Eventually I figured out that the RAW files were showing the same date/time as shown on my laptop, which was set to my home time (PDT in California), rather than the actual time in Africa that the shot was taken, but the JPG files showed the correct (Africa) capture time. When I subsequently changed the date/time on the laptop to correspond with the actual time (the camera had always been set to the Africa time), then the RAW and JPG capture times from that point on were correct and agreed with each other. While I’m wondering if anybody can explain what happened here (and have submitted this to a photography forum, my immediate concern for this forum is whether there is some way to automatically change all the incorrect dates and times to the correct ones. The file names have identical beginnings but different extensions, e.g., a RAW photo might be 12345.CR2 and the identical JPG photo would be 12345.JPG and I want all the RAW photo dates/times be the same as the JPG photo dates/times. Attached is a screen shot of a couple of examples of what this looks like:

NeatNet examples.docx (22.2 KB)

drcard
Software Review Panel

Posts: 580

Time stamp on photographs (yes there is a computer question) Nov 7, 2019 20:30:38 GMT -5

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Post by drcard on Nov 7, 2019 20:30:38 GMT -5

Hi risman,

Right click each file and select Properties. Select the Details tab. Look under Origins for Date taken. Are the times listed in Properties the same for the JPEG and CR2 photos taken at the same time? If so then, does the date and time taken in the Properties of the CR2 files match the date and time shown in Explorer for creation of those files? If they do not match then, the problem may be Windows decoding the CR2 format. There are many different RAW formats and sometimes Windows codecs can't decode the photo meta data correctly. When downloaded to Windows instead of giving the photo file the creation date and time as when it was taken, it gives the date and time the file was downloaded from the camera. If the date and time of the Details tab has the wrong date and time, then I am at a loss to explain that.

Last Edit: Nov 7, 2019 20:32:08 GMT -5 by drcard

HTH, Dana:)) 👨‍🔬

risman
New Member

Posts: 42

Time stamp on photographs (yes there is a computer question) Nov 8, 2019 12:15:45 GMT -5

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Post by risman on Nov 8, 2019 12:15:45 GMT -5

For the CR2 files, there is nothing showing under Date Taken, but under File, there is a Date Created, which shows the (incorrect) laptop PDT date and time; Date Modified, which shows the correct Zambia time; and Date Accessed, which again shows the (incorrect) laptop date and time.

For the JPG files, the Date Taken shows and is correct; the Date Created shows the (incorrect) laptop PDT date and time; and Date Modified, which shows the correct Zambia time. There is no Date Accessed field.

The good news in all of this is that I just discovered that the time stamp on the actual images (using a raw file viewer) is correct.

risman
New Member

Posts: 42

Time stamp on photographs (yes there is a computer question) Nov 8, 2019 12:17:10 GMT -5

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Post by risman on Nov 8, 2019 12:17:10 GMT -5

And I should add that my original request for a clever programmer should be ignored, as the images themselves have the correct time stamp on them. But I'd still like to know if this happens routinely or is an anomaly.

drcard
Software Review Panel

Posts: 580

Time stamp on photographs (yes there is a computer question) Nov 8, 2019 15:17:51 GMT -5

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Post by drcard on Nov 8, 2019 15:17:51 GMT -5

Hi risman,

There are many different RAW formats and each stores the meta data (date and time taken, resolution, etc.) in a different portion of the photo file. Windows has codecs that allows Windows get the meta data from the photo file. When Windows gets the date and time the photo was taken, it uses that date and time as the creation of the file. If Windows can't decode the meta data from the photo file, Windows will use the date and time the file was downloaded to the drive. After a camera manufacturer (like Canon) creates a new RAW file format, it creates the codec for Windows to be able to access the meta data in this RAW format. It submits the codecs to Microsoft which in turn includes the new codecs in a future update. The time gap between creation of the RAW format and Windows update with the new codecs can be quite long. A newly release camera with the newly created RAW format may take months before an updated Windows can access the meta data. The best you can do is keep Windows updated.

Last Edit: Nov 8, 2019 15:18:43 GMT -5 by drcard

HTH, Dana:)) 👨‍🔬

risman
New Member

Posts: 42

Time stamp on photographs (yes there is a computer question) Nov 8, 2019 17:51:46 GMT -5

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Post by risman on Nov 8, 2019 17:51:46 GMT -5

Well, it turns out there is a company--SoftFamous--that has a Canon Raw codec. I installed it, and it changed all the wrong time stamps to the correct ones! However, when I tried to just open a photo after installing the codec, it wouldn't open it, and it gave me a link to a new Microsoft Raw codec. After installing it, I can open the raw photos in the MS Photo app. So there is a silver lining to all this. Thanks for all the time you've spent going over this with me.