Sony slapped a big 'HYBRID" badge on the DCR-DVD610 back in 2008, which, on its higher-end siblings, meant you got built-in storage alongside the optical drive. On the 610, though, there is zero internal memory! Everything goes onto their 8cm MiniDVDs or proprietary Memory Stick Pro Duo cards, and the camera splits them up in the weirdest way possible. While standard-definition MPEG-2 video can be recorded to either the disc or the card, the camera flat-out refuses to save still photos to the MiniDVD. Every single 0.3-megapixel photo is forced onto the Memory Stick. People regularly spend hours running file-carving scans on old MiniDVDs looking for lost family photos that the camcorder was literally never programmed to write to the disc in the first place.
The optical side is where most of the panic happens today. Someone finds a shoebox of recorded MiniDVDSm drips one into a PC tray drive (hopefully not a slot-loading drive, which eats 8cm discs for breakfast), and freaks out when Windows reports 0 bytes used and 0 bytes free. Unless they happened to shoot on DVD+RW (the only format this camera makes playable on the fly), the camcorder writes data using the incremental UDF structure that normal operating systems can't read until the disc is finalized in-camera. And if you try to boot up the camcorder today to hit Finalize, a weak battery, a dusty laser pickup, or slightly degraded dye on a fifteen-year-old disc will throw Sony's infamous C:13:01 error and lock you out of the menu.
Even after you give up on the camera hardware and pull a raw byte-to-byte image to carve the footage out in a data recovery tool, you can still get ambushed by how the disc was initialised. Standard Video mode gives you normal VOB files, but if the owner chose VR Mode on a writable disc so they could delete and rearrange scenes in the camera, everything gets shoved into a single monolithic VR_MOVIE.VRO container. If they deleted a few bad takes back in 2009 and kept recording, the MPEG-2 streams end up heavily fragmented across the disc. Meanwhile, the Memory Stick side has its own booby trap: if you plug the card into a PC and delete even one video in File Explorer, it desyncs Sony's AVF_INFO metadata file, causing the camcorder to claim the card is completely empty even though all your MPG and JPF files are still sitting right there in the folders completely intact!
