topic Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card in Camera Software

EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

jesidh2r — Fri, 08 May 2026 21:09:07 GMT

Is there a way to export edited photos using Lightroom back into the cf express card and be able to view that same photo in the camera? I’m using an r5 mk 2

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

Waddizzle — Fri, 08 May 2026 22:14:13 GMT

No, the camera will ignore files written to the card by other devices.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

ebiggs1 — Sun, 10 May 2026 14:44:11 GMT

"No, the camera will ignore files written to the card by other devices."

I don't know about that. I haven't done it nor do I see why anyone would want to do it but I see no reason why you can't. Use a Card Reader. Copy to the DCIM Folder on the CF card. Use the correct subfolder which might be 100CANON for example. You must use the same naming structure that Canon uses, I.E. IMG_0021.JPG. You may need to rename the file in order for the camera to see it. Bottom line here is you must use the exact file structure the camera uses.

Give it a try and let me know if it works. However, I am curious why you want to do this. The CF is not a photo storage device and shouldn't be thought of as one. It is best practice to get your photos off the CF as soon as possible and onto a computer, etc.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

johnrmoyer — Sun, 10 May 2026 17:10:32 GMT

Since the standard requires digital cameras to use DCF, the file names must be compatible.

Also, the metadata will need to be recognized by the camera so it will likely be necessary to copy the metadata including make, model, and makernotes for the same straight out of camera JPG file to the edited file. It appears to me that as a safety feature, the camera will not mess with unrecognized files.

https://en.wikipedia.org/wiki/Design_rule_for_Camera_File_system

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

ebiggs1 — Mon, 11 May 2026 14:25:34 GMT

I still would like to know why. For the life of me I see no good reason to do it.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

johnrmoyer — Mon, 11 May 2026 14:40:58 GMT

@ebiggs1 wrote:

I still would like to know why. For the life of me I see no good reason to do it.

The why is that in ancient times the camera manufacturers agreed to create and adhere to a standard.

The 8.3 naming is because it was in ancient times.

The not loading unrecognized files is to avoid crashing the firmware in the camera (this one is conjecture on my part, but I might have done the same if I had written the firmware).

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

Waddizzle — Mon, 11 May 2026 15:22:06 GMT

“ I don't know about that. I haven't done it nor do I see why anyone would want to do it but I see no reason why you can't. “

I have not tried it in years. All I know is that it didn’t work. There’s some skullduggery going on underneath the surface. The can tell which files have been previously downloaded, too. There is nothing in the EXIF or other file properties to tell you that.

Even if you try to write a copy of a file you downloaded, the camera will not recognize it.

[EDIT] I just reread the question. If you’re trying to write something on a memory card that is still inside the camera, that is simply not allowed. You can read the card in the camera. But you may not write to a card inside a camera.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

Stephen — Mon, 11 May 2026 20:19:20 GMT

A design rule, or even an IEEE standard, doesn't dictate the data inside the file. It just means it follows a schema.

If anything modifies the file's data, the built-in image renderer may not be able to decode the image, and we make no guarantees one way or the other.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

March411 — Tue, 12 May 2026 15:17:04 GMT

Just for the heck of it I tested moving files back onto a card. Shot the images on the R5 MkII using Lexar 256 CF and SD cards.

They were moved off the card using a card reader. Once they were off the cards I formatted the cards in camera. Again using the card reader I moved the files back onto the card into the appropriate Canon directory and directly onto the card in no directory. The images moved back into the appropriate locations but when I attempted to view the images in the camera it displayed a no images message.

So yes you can move them back for storage but you cannot view them in camera. I also shot a couple frames on these cards just to wrap up the test. The new images wrote to the card and were viewable.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

ebiggs1 — Wed, 13 May 2026 14:41:38 GMT

"The why is that ...."

My query was not why Canon does or does not allow you to do that but why would anyone want to put images back on the CF. There is no good reason to do that I can think of.

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

ebiggs1 — Wed, 13 May 2026 14:47:57 GMT

"The not loading unrecognized files is to avoid crashing ..." "So yes you can move them back for storage but you cannot view them in camera."

So, moving them back is possible but viewing them is not possible. I doubt it is a crash avoiding thing since they are there and occupying space. There must be some tag or something that the camera wants and is not seeing in order to view them

Re: EOS R5 Mark II, How to export edited photos using Lightroom back into the CF express card

ebiggs1 — Thu, 21 May 2026 13:42:38 GMT

"I formatted the cards in camera."

Why? Try it without formatting the CF. No need to do that. Also the file name must be identical.