Empty folders...images missing?

[Fred_Salamon]

I have several SanDisk cards ( Ultra II and Extreme III) that were shot in a Canon 20D.
There are overlapping folder numbers spread across the cards.
For example, Card 1 has folder number 116 as does card 2. Card 1 folder number 116 has images in it, card 2 folder number 116 does not.
All the cards in question were used in only one camera body.
At times I rotated out cards to minimize the risk of having all the images of a particular subject on one single card.
Can anyone explain what's going on here? Am I missing images or does the 20D create empty folders?
I would appreciate any help.
Fred

[Charles_Beasley]

An empty folder when switching cards isn't unusual.

[Jim_Townsend]

First.. If you have your camera file numbering set to continuous, it will always remember the last image number even if you put another CF card in the camera. The only time the numbering will change is if the card has HIGHER image numbers than your camera. In that case, the camera will pick up the higher number off the card and continue with that.

There is a new folder created for every 100 images. The folder number is tied to the image number.

For instance when your camera gets to image IMG_1600, it will create a folder called 016CANON. All the images you take will go into this folder until the image numbers get to IMG_1700. A new folder called 017CANON will be created to hold the next 100 images, then 018CANON and so on...

If you erase your images using the camera, the images get deleted, but the folders remain. The only way to get rid of these folders while the card is in the camera is to select "format" in the camera menu. If you use a card reader, you can delete these folders using your computer.

Even if you do delete all the folders, DCIM and the folders inside DCIM that hold the images will be recreated again. So if you put a blank card in your camera, and your next image is IMG_1890, the camera will create folder 018CANON to put it in. This will hold 10 more images.. When the count gets to IMG_1900, then folder 019CANON will be created.. When you look at folder 018CANON, you'll see it only has 10 images in it. The other images would be on the folder(s) that were created on the other flash card(s)..