topic Re: Where are DPP4 edits stored ? in Camera Software

Where are DPP4 edits stored ?

smbjerke — Sun, 27 Aug 2023 19:33:02 GMT

It appears edit to raw (.cr3) files are stored within the raw file itself, but where does DPP4 store / maintain edits to .jpg files ? Is this documented somewhere ?

Re: Where are DPP4 edits stored ?

rs-eos — Sun, 27 Aug 2023 19:44:32 GMT

I don't use DPP, but I would be shocked if it would be modifying RAW files. Edits, as with Adobe Lightroom, should be stored to different files to keep the RAW files as-is (effectively treating them as being read-only).

Edits to JPEG may not be non-destructive perhaps? And thus the JPEG file gets overwritten? If not, I would expect that edits are also stored to different files the same as for RAW.

Re: Where are DPP4 edits stored ?

smbjerke — Sun, 27 Aug 2023 20:37:04 GMT

Hi Ricky,

Thanks for the comment, but if you have a read here you will find this (after som scrolling or text seach):

Overall Benefits of DPP

DPP has always been a very easy-to-use tool that delivers very high quality RAW conversions.
DPP is especially good at getting pleasing color.
That DPP stores recipes directly in the RAW file means that there is no catalog to maintain and no sidecar files to keep track of and makes file management as easy as drag and drop.

So, perhaps Canon has thought of a similar aproach to JPG files... ?!

- Sjur

Re: Where are DPP4 edits stored ?

Anonymous — Sun, 27 Aug 2023 23:26:08 GMT

It is documented in the user manual for DPP.

Use save as when saving a jpg file to avoid overwriting the original file. If you use save, it will overwrite the original file. https://cam.start.canon/en/S002/manual/html/UG-04_EditImage_0170.html

Re: Where are DPP4 edits stored ?

Peter — Mon, 28 Aug 2023 03:59:49 GMT

Edit an older file, like CRW or CR2, and save. Use Exiftool to compare what has been changed.

Re: Where are DPP4 edits stored ?

jrhoffman75 — Mon, 28 Aug 2023 12:45:54 GMT

As discussed in the manual:

A recipe is appended to an edited file. The recipe can also be saved as a recipe file and then applied to multiple files. The actual file image data is not modified. If you execute a "Save" or exit DPP and choose the Save edits option the edits are saved but the image is not modified. You can re-open DPP and re-edit the file or restore to original. This applies to RAW and JPEG files. Finalized edited files are not created until a Convert & save operation is executed.

Re: Where are DPP4 edits stored ?

Peter — Mon, 28 Aug 2023 13:13:29 GMT

At least the raw file is modified. I checked sha256 checksum for a raw file before, after and when I had reset it again to the same value.

I know Nikon has corrupted its raw files when transferring the files from the camera to the computer so modifying the raw file is a bad idea. Exiftool creater Phil Harvey has even created a script for those corrupted Nikon files.

I don't know if EOS Utility touches the raw files when importing them. I only have EOS Utility in a Virtual Box and struggle to import from camera. Anyone who wants to see if Canon changes anything in the raw file during import can compare sha256 checksum before importing a file and after. There are online tools for sha256 checksum if you don't know how to do it in CMD/Terminal.

Re: Where are DPP4 edits stored ?

jrhoffman75 — Mon, 28 Aug 2023 13:13:04 GMT

@Peter wrote:
At least the raw file is modified. I checked sha256 checksum for a raw file before, after and when I had reset it again to the same value.
I know Nikon has corrupted its raw files when transferring the files from the camera to the computer so modifying the raw file is a bad idea. Exiftool creater Phil Harvey has even created a script for those corrupted Nikon files.
I don't know if EOS Utility touches the raw files when importing raw files. I only have EOS Utility in a Virtual Box and struggle to import from camera. Anyone who wants to see if Canon changes anything in the raw file during import can compare sha256 checksum before importing a file and after. There are online tools for sha256 checksum if you don't know how to do it in CMD/Teeminal.

The RAW file is modified in the sense that the edited recipe data is added to the file. But the original image data is not affected because any edits can be reset to the starting point. Files that have been edited in DPP can be opened in Lightroom and the image is original. None of the DPP edits show. Same holds true for JPEG.

Re: Where are DPP4 edits stored ?

Peter — Mon, 28 Aug 2023 13:44:36 GMT

The image data in the raw file seems to be untouched, yes.

Re: Where are DPP4 edits stored ?

smbjerke — Mon, 28 Aug 2023 14:48:31 GMT

Thanks !

I was hoping it would work like this !

Sjur Bjerke, Stavanger

Re: Where are DPP4 edits stored ?

Peter — Tue, 29 Aug 2023 02:13:15 GMT

About Nikon corruption https://exiftool.org/forum/index.php?PHPSESSID=6a4657a4d4b3ceffb5cbdea55aabafe7&topic=4220.0

and

https://discuss.pixls.us/t/very-different-initial-rendering-of-raw-file-possible-corrupt-file-but-renders-ok-in-rt/35297/

I guess this part from the Rawspeed maintainer includes Canon:

As it has been said, nobody should ever use any program that modifies the original raw files for any reason whatsoever, including “harmless” sidecar embedding.

But I have never ever heard anything about raw file corruption due to DPP or EOS Utility.

One interesting thing is that DPP4 doesn't support new features, like ALO, in older raw files. So the "embedded sidecar" must be limited to already writable metadata fields for each camera model.

I will not have any access to a computer during a month so I can't analyze the metadata fields myself right now.