Using the SD card sometimes after installing filesystem on USB stick?

Question

My question might have been a little confusing, so let me clear it all up:

I have installed the filesystem for my RPi on a USB stick to preempt the corruption of the data on my SD card. That's all fine and dandy, and it seems to be working. Unfortunately, my SD card is now far too big for its breeches.

I used an 8 GB card, mainly because it was all I had. So, I'd like to find a way to use all that space. My idea is that I could simply use the SD card to save camera images on, once my Pi camera gets here. Since SD cards are essentially designed for this type of use, I figure it is a good way to avoid corrupting anything, and I will be able to use all that extra space that would otherwise go to waste.

To conclude, I'll bold a tl;dr:

Can I use the SD card to store rarely-used files while using the USB filesystem that I already have in place for everything else?

Answer 1

You can make multiple partitions, no problem. The issue however is whether or not the camera supports multiple partitions.

Also the rasberry OSs have a small fat32 partition at the beginning of the SD card, for storing the bootloader, and kernel. So your camera should skip this first partition, and also the second EXT4 partition. And only use the third fat32 partition you create into the free space at the end.

Alternatively you could move the ext4 partition to the end of the SD card, and extend the first fat32 partition. That way both Raspbian and the camera can use the fat32 partition. Since most cameras put their files nicely into separate folders, the filesystem won't be a mess bunch of files. This solution has the most chance of working on your camera.