One logical thing I can think of, is that the camera took the pictures on its internal memory.
You can find out by removing the memory card from the camera and then turn-on the camera and look at the photos left in the camera.
With the memory card removed you will be seeing internal memory photo files only.
See if you find your missing photos on internal memory.
....
Another possibility:
You are using a memory card that has too much capacity.
Older cameras can not read SDHC (SD High Capacity)
A SDHC card is any card that has a capacity of 4 gig or greater.
.....
Another possibility:
You are using an older card reader with a SDHC memory card.
Older card readers cannot see all the memory on SDHC memory cards.
..
I went hiking with my dog and took about 15 pictures and one movie. When we got back to the car, I reviewed some, but not all, of the photos, turned the camera off and stuck it in my bag. I had other photos on the camera that I took recently. When I got home and took the card reader out of my Panasonic Lumix DMC-FX07 to upload them to my computer, all of the photos and video from that day were gone. I just can't make sense of what could have gone wrong. I'm sad to have lost the photos and would love to recover them but I'd mainly like to figure out what the problem could be because I feel like I can't trust my camera until I've found a rational reason.
1) The memory card wasn't full
2) Although the camera was in a bag on the seat of the car, I think it is extremely unlikely that it would have turned itself on, then deleted (with confirmation for each) ONLY and ALL of the photos from that afternoon leaving all of the other photos in tact.
3) A card reader and photo recovery scan returned no evidence of the photos or video. (Wondershare) This lends further evidence to the fact that the photos were not deleted because they should have been recovered.
4)I know the photos saved initially because I reviewed them 3 hours after they were taken when I was back at the car.
5) I reviewed some, but not all of the photos so even if the card weirdly corrupted after I reviewed some, one or 2 pictures or at least the video seem like they would still be there.
I'm completely mystified.

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