C300: Dual Slot Record mode not writing evenly to both cards?

L

Lkorver

Well-known member
C300mk2:
After a recent card failure, I've started shooting with dual slot recording. I've noticed while filming, when I'm nearing capacity on the cards that one card with have more data remaining than the other.Pop it in the computer to see that the camera will be writing to both cards, but for a few chunks of sequential clips, it will write only to one card and not the other. So you'll have one card that got 120gb on it and another with only 110gb for example. Firmware is 1.1.2.1.00

While all my cards are Sandisk 128gb, some are the newer cards with the "130 film slate" decal while the others are the older versions. The only thing I can think of is the camera doesn't like recording to an old and new card at the same time, which I didn't note if the issue had occurred in this scenario or not (but I will check moving forward)

To set up dual slot recording, I'm setting "DOUBLE SLOT RECORDING" to "ON". Am I missing another step?

Any idea what might be causing this? I use 8 different cards (4 pairs) and it seems to happen with all of them.
 
Last edited:
Do you have matching video files on each card? Or are you just going by the storage space available when read on a computer? Does the camera identify the remaining minutes on the cards identically?

I think it's a best practice to use dual slot recording with two identical cards but it's maybe not necessary. I also imagine the newer Sandisk CFast are allocating the space a little differently (DriveDX has flagged a number of the older 128GB Sandisk CFast I've encountered with pre-warning failures and Sandisk has replaced these for us under warranty with the VPG-130 versions).

Also, if you're working in macOS Mojave, I've had it report some funky storage parameters on memory cards (I've had it show more storage than is possible on a 128GB CFast for example).

I work mainly on a C200 and using dual slot mode on that with two matching Angelbird cards I've had no issues. I have a C300 MK II shoot coming this weekend so perhaps I can report back on what I find there
 
That's strange. My inclination too would be to only dual slot record to identical media as a first step.
Eliminate the variables is always the first stage of troubleshooting so set up recording on two identical size and formatted cards and dual record and see if then you are getting the same result.
Then you will either confirm or eliminate that first variable of not having matching media. Depnding on the result, you can then move to the second or third stages which might involved checking the camera firmware version, iOS used, etc.?

There are no other C300 MKII settings to check for dual recording that I know of. Use identical media and see what happens.
 
puredrifting said:
That's strange. My inclination too would be to only dual slot record to identical media as a first step.
Eliminate the variables is always the first stage of troubleshooting so set up recording on two identical size and formatted cards and dual record and see if then you are getting the same result.
Then you will either confirm or eliminate that first variable of not having matching media. Depnding on the result, you can then move to the second or third stages which might involved checking the camera firmware version, iOS used, etc.?

There are no other C300 MKII settings to check for dual recording that I know of. Use identical media and see what happens.
Click to expand...

Agreed. That is weird. I've recorded dual slot recording exclusively for quite some time and have not experienced this behavior. Unfortunately, I don't have both 'old' and 'new' sandisk cfast 2.0 otherwise I'd try to recreate.

If there's no fix after going through the steps @puredrifting suggested, it might be a good idea to see if there are some weird hidden partitions on the card(s). Also possible to take a look at them and clean them up with DiskWarrior or the like.
 
I've been doing dual slot recording with Transcend and ProGrade cards. That is Transcend in one slot, Prograde in the other. Did it to initially test the Prograde card, but that sort of became my workflow protocol. Have not had a problem to date.

As others have suggested, backtrack workflow, test to failure. It may be a hardware/software problem with camera. Don't know.
 
Are you shooting any 120p? Certain settings will disable dual-slot recording, like 120p. So while you're in 120p, the file will only write to one card, and then dual slot is automatically re-enabled when you go to a lower frame rate.
 
drummondb said:
Are you shooting any 120p? Certain settings will disable dual-slot recording, like 120p. So while you're in 120p, the file will only write to one card, and then dual slot is automatically re-enabled when you go to a lower frame rate.
Click to expand...

I did shoot some 120p, but didn't think about that when checking the difference between the clips that went to both cards and the ones that only went to one slot. On a shoot this week, i'll troubleshoot and let the board know what i find.
 
Lkorver said:
I did shoot some 120p, but didn't think about that when checking the difference between the clips that went to both cards and the ones that only went to one slot. On a shoot this week, i'll troubleshoot and let the board know what i find.
Click to expand...

It will only record to one card when you change to 120p so that should be the answer to your problem.
 
I have noticed the same thing with dual card recording on my c200. I did this as I was having issues with a corrupted card. Anyway I actually managed to use some software to get the shots off the corrupted card. Now here is the thing. When I looked at the structure of the files using the recovery software there were a lot of short clips say 3 seconds or so that were corrupted. My guess is that they are PRE-RECORDING shots that the camera has done but as this was not switched on they are ignored when you upload the clips to edit. The A card always has an extra minute or so of files. Maybe this is what's going on.
 
You must log in or register to reply here.
Back
Top