I have the R5 body with 100-500 lens. I shoot solely using the appropriate custom mode, C1, C2 or C3. All three modes are set to record both stills and video to Card 1, SanDisk Extreme PRO CFexpress 512GB Read 1700/Write 1400MB/s. Card 2 is Toshiba EXCERIA PRO SDXC I, 64BG 260MB/sThat has worked OK until this morning when I found that files had been recorded to Card 2 and the images were fine. A check of all three modes showed they were still set to record both stills and video to Card 1.I removed Card 2 and shot some images which were, this time, recorded to Card 1. Reinserted Card2 and shot some images which, again, were recorded to Card 1.  Nothing was recorded to Card 2.Has anyone experienced this before?

If I am not wrong, you probably take your cf express card out of camera to download with a reader. That will reset your destination when you shoot again to sd slot.If you shoot 8k raw, it won’t let you record as sd card is not fast enough with 8k raw just need to reset destination of storage if you take cfexpress card out of its slotall the best

Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.

JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.Yes. I have had that problem with my R6. In the end, I solved it by leaving slot 2 empty.Life is too short to have to pander to technology in order to avoid such irritations!David

davidwien wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.Yes. I have had that problem with my R6. In the end, I solved it by leaving slot 2 empty.Life is too short to have to pander to technology in order to avoid such irritations!DavidThanks, that's what I had considered doing.  I don't know why I have a card in slot 2 anyway.

bestzoom wrote:If I am not wrong, you probably take your cf express card out of camera to download with a reader. That will reset your destination when you shoot again to sd slot.Thanks, yes I do use a card reader to download.If you shoot 8k raw, it won’t let you record as sd card is not fast enough with 8k raw just need to reset destination of storage if you take cfexpress card out of its slotall the best

JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.You can set the priority card so that the R5 will go back to card you select when the card door was closed previously with the slot empty.Yellow wrench menu 1, choose "Record func+card/folder sel." option, then in the "Play" and "Record/play" options you can set the priority card.James

jckk wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.You can set the priority card so that the R5 will go back to card you select when the card door was closed previously with the slot empty.Yellow wrench menu 1, choose "Record func+card/folder sel." option, then in the "Play" and "Record/play" options you can set the priority card.JamesThanks, have done that.

JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.This issue has been discussed on this forum for as long as the R5 has been out.It is important to note that theR5 is NEVER truly off while there is a battery in the camera,and both the card and the battery door are closed.If you look a the red light on the back of the camera when you close the card door, you will see it flash. The camera reads the status of the card slots, and if one is empty and the cards are in the auto-switch mode, it will switch the card in the camera. Then when you replace the other card, it will not switch back.I have gotten the habit of leaving the door open when downloading a card. I also routinely check the "Q" (quick menu) to ensure the camera is on the desired card.

davidwien wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.Yes. I have had that problem with my R6. In the end, I solved it by leaving slot 2 empty.Life is too short to have to pander to technology in order to avoid such irritations!DavidI think this is a lousy answer based on not understanding how the camera works.This answer effectively makes the 2nd slot unusable. It also risks there being NO card in the camera if you take off without checking first (also a good idea to keep some extra SD cards in the bag)The R5/R6 reads the status of the slots when the card door is closed. If one slot is empty, it will switch to the filled slot.A better answer is to leave the door open until the card is returned. This has two advantages:

davidwien wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.Yes. I have had that problem with my R6. In the end, I solved it by leaving slot 2 empty.Having two card slots and two cards and not using the second slot doesn't look right.Life is too short to have to pander to technology in order to avoid such irritations!Exactly. Technology fails, memory cards fail sometimes, that's why top end Canon cameras have the second slot - for backups (second use is additional memory capacity).

Karl_Guttag wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.This issue has been discussed on this forum for as long as the R5 has been out.It is important to note that theR5 is NEVER truly off while there is a battery in the camera,and both the card and the battery door are closed.If you look a the red light on the back of the camera when you close the card door, you will see it flash. The camera reads the status of the card slots, and if one is empty and the cards are in the auto-switch mode, it will switch the card in the camera. Then when you replace the other card, it will not switch back.I have gotten the habit of leaving the door open when downloading a card. I also routinely check the "Q" (quick menu) to ensure the camera is on the desired card.Thank you all for your most helpful posts.  Much appreciated.

Glad to help. I was concerned that you had accepted an answer from someone that didn't know better.BTW, along with the "camera is never completely off as long as there is a battery in the camera" theme, leaving the battery in the camera will cause it to drain slowly—the on-off switch is a software switch. This catches people out if they leave their camera for many days and then find the battery low when they go to use it.Opening the battery (or card) door might prevent the draining, but I have not tested it. If I don't think I will use the camera for a while, I will just pop the battery half-out just in case. I also have 3 Newer "clone" batteries, and I usually leave one of them in the camera when at home so I don't put "wear" the two Genuine Canon LP6NH batteries.MarkDavo wrote:Karl_Guttag wrote:JamieTux wrote:Yeah if you have cards in both slots and take a card out and close the door it auto switches to just the other card and doesn't auto switch back.Its annoying but once you realise its easy to deal with and check for.This issue has been discussed on this forum for as long as the R5 has been out.It is important to note that theR5 is NEVER truly off while there is a battery in the camera,and both the card and the battery door are closed.If you look a the red light on the back of the camera when you close the card door, you will see it flash. The camera reads the status of the card slots, and if one is empty and the cards are in the auto-switch mode, it will switch the card in the camera. Then when you replace the other card, it will not switch back.I have gotten the habit of leaving the door open when downloading a card. I also routinely check the "Q" (quick menu) to ensure the camera is on the desired card.Thank you all for your most helpful posts. Much appreciated.

I thought this was no longer true?Certainly on my R3 you can set the priority card and it will always go back to that card so you avoid all this old open door stuff?

expro wrote:I thought this was no longer true?Certainly on my R3 you can set the priority card and it will always go back to that card so you avoid all this old open door stuff?Jck gave settings that worm as I wanted it to up in the thread, until someone mentioned that I did as someone else said and keep the door open, or if it's more time consuming and I dont want to leave the door open take the battery out to charge too.I'm not sure what I said that was so wrong Karl had to correct it with the same advice though 😅

Karl_Guttag wrote:Glad to help. I was concerned that you had accepted an answer from someone that didn't know better.BTW, along with the "camera is never completely off as long as there is a battery in the camera" theme, leaving the battery in the camera will cause it to drain slowly—the on-off switch is a software switch. This catches people out if they leave their camera for many days and then find the battery low when they go to use it.Opening the battery (or card) door might prevent the draining, but I have not tested it. If I don't think I will use the camera for a while, I will just pop the battery half-out just in case. I also have 3 Newer "clone" batteries, and I usually leave one of them in the camera when at home so I don't put "wear" the two Genuine Canon LP6NH batteriesI've noticed that my new LP-E6NH batteries that I got with my R5 & R6 have gone from three green bars to two green bars more quickly on the R5 & R6 than the LP-E6N ever did on my various DSLRs (5D, 6D, 7D Mark II, 5D Mark IV). I wonder if this might be part of the reason.... Unfortunately I recycled my old third party batteries when they got too weak, so I can't use your strategy. Maybe I should leave my older one red bar batteries in the cameras and only insert the newer green bar batteries when I am leaving for a shoot.

In almost 20 years of shooting thousands of files I've only partially lost files on a 5D1. Since then when I'm traveling I download to portable hard drives every night. Now with R5 I don't worry about losing files because I record the files to both cards and don't do the nightly download. Also I very seldom shoot video and have never shot 8k.Kent

expro wrote:I thought this was no longer true?Certainly on my R3 you can set the priority card and it will always go back to that card so you avoid all this old open door stuff?I just rechecked (I have not tried it in over a year), and the R5 with the latest firmware (1.7) still swaps cards if the door is closed with the card removed if in "Standard" or "Auto-Switch" mode. In dual record mode, it will not change.On the R5, You can only set "Priority" to the Express SD slot but not the MicroSD slot. If you set Priority to the Express SD slot, it will stay locked on that card, even if the door is closed with the Express SD removed. There is no option to set priority to MicroSD.I think the behavior many people would want it to stay with the given card slot, at least until the camera is turned on.When I am just shooting around with no need for high performance, I use the MicroSD as they are much less expensive to replace if I damage one, and I have many MicroSDs but only one Express SD.  I suspect others behave similarly.

JamieTux wrote:expro wrote:I thought this was no longer true?Certainly on my R3 you can set the priority card and it will always go back to that card so you avoid all this old open door stuff?Jck gave settings that worm as I wanted it to up in the thread, until someone mentioned that I did as someone else said and keep the door open, or if it's more time consuming and I dont want to leave the door open take the battery out to charge too.I'm not sure what I said that was so wrong Karl had to correct it with the same advice though 😅I wasn't picking on you😊 , I was concerned because the OP had picked the correct answer to be to leave the other card slot empty, which I thought was a terrible solution as it risked there being no card in the camera. So I pounded home the leave the door open answer.

CameraCarl wrote:Karl_Guttag wrote:Glad to help. I was concerned that you had accepted an answer from someone that didn't know better.BTW, along with the "camera is never completely off as long as there is a battery in the camera" theme, leaving the battery in the camera will cause it to drain slowly—the on-off switch is a software switch. This catches people out if they leave their camera for many days and then find the battery low when they go to use it.Opening the battery (or card) door might prevent the draining, but I have not tested it. If I don't think I will use the camera for a while, I will just pop the battery half-out just in case. I also have 3 Newer "clone" batteries, and I usually leave one of them in the camera when at home so I don't put "wear" the two Genuine Canon LP6NH batteriesI've noticed that my new LP-E6NH batteries that I got with my R5 & R6 have gone from three green bars to two green bars more quickly on the R5 & R6 than the LP-E6N ever did on my various DSLRs (5D, 6D, 7D Mark II, 5D Mark IV). I wonder if this might be part of the reason.... Unfortunately I recycled my old third party batteries when they got too weak, so I can't use your strategy. Maybe I should leave my older one red bar batteries in the cameras and only insert the newer green bar batteries when I am leaving for a shoot.I think (not 100% sure) if you open either the card door or the battery door, the camera is completely off. To be safe, you can half pop out the battery. The downside of this is that there is some risk of the battery door getting damaged. I don't see any reason to put a dead battery in the camera and there might be some risk of it going "really bad" and damaging the camera.