Hello,
first of all - please, I am not an expert and therefore my question might be clear to you but I am not professional in IT.
I am looking for information whether a RAW file - specifically .CR2 is reliable source of information about the date when the photo was taken.
I need to prove that I took pictures of mould in our flat in August 2011. I have the photos in the original RAW format and the exif confirms the date. I have not found the information throughout the internet that the exif can be changed while preserving the original RAW format.
Please can you advise me on that or perhaps can you confirm that?
Thank you very much in advance.
If it is possible to read metadata from a file, then it is possible to modify it. For example, ExifTool has the ability to modify almost anything it can read, but in most cases it is possible to tell if ExifTool has modified a file. This might not be true for other editing software however.
In metadata, as a general rule, it is never possible to prove that something is authentic. But it may sometimes be possible to prove that it is not.
- Phil
Thank you, I know it is possible to change the exif. But can you preserve the CR2 format with this information?
For example when you open CR2, you generate file xmp, then you save it is jpg. I am sure you can change information in these files.
But when you open CR2 next time, the date remains the same - or it is not true?
It is raw data not really a file as far as I understand....
So the information should not stay there?
Than you very much
I don't know exactly what you are asking, but it should always be possible to preserve the CR2 format format when editing metadata. (ie. Any software able to display the CR2 image should behave the same for a file before or after its metadata is edited.)
- Phil
are you saing that I canot use my photo in CR2 as a proof?
If some sotware changes the date, it will stay in CR2 format and when you open it, the date will be changed?
I thought that you can always tell it was changed... therefore it is raw data. But I guess I am wrong.
I thought you can change it but only one way - not back - that is is somehow encrypted....
Quote from: monae on November 11, 2019, 10:00:45 AM
are you saing that I canot use my photo in CR2 as a proof?
If some sotware changes the date, it will stay in CR2 format and when you open it, the date will be changed?
Yes. That is what I am saying.
QuoteI thought you can change it but only one way - not back - that is is somehow encrypted....
The metadata in some raw images is encrypted, but the encryption algorithms are known.
- Phil