WHAT are these SHADOWS in my pictures???

[LD67]

I just got my Rebel t3 about a week and a half ago. The majority of my pictures have been fine, but quite a few also have this weird shadow in them! These pictures were shot in raw using the Auto setting. Any idea id i'm doing something wrong, or is my camera defective??? 

Here's a link to where i have a few of the pictures with the shadows in them: Shadows - a set on Flickr

Thanks for any info you can give me!!!

[Skirball]

Those are some odd shaped shadows.  Do they change position with every shot?  If you take off the lens do you see anything floating around back there near the sensor?

[hsbn]

what lens are you using? Does it has a lens hood?

[LD67]

i only have the one lens that the camera came with, and no, there is no hood.

i've taken about 300+ pictures so far, and about 15 have this odd shadow.

i have no strap on the camera, my fingers were not in front of the lens or flash.

i'm at a total loss here.

[diverhank]

These look like obstructions to the flash. My guess is that these were taken using your popup flash and something (like your hat or your hand is partially depressing the flash down and part of the beam is hitting the lens, creating the shadows.  Either that or a goblin is doing the deeds (I actually got the creeps thinking about it).

[LD67]

nope, there were no hands, fingers, straps, hat, hair, goblins, gremlins, OR ghosts involved.

what are the chances i just have a broken camera?

[7D5D]

Study your exif data and see if there are any patterns on your shadowy photos. Maybe you will find a common shutter speed, aperature setting, focal length, or even flash setting. If you find a pattern, or even a slight pattern, try to duplicate it with another lens and on a tripod. This might help you narrow it down and provide some data for when you call Canon Support. If you find something obvious that determines the camera is defective, then I'd return it. Please keep us posted on the outcome.

Edit: use a tripod and timer just to rule out any accidental interference, fingers, hat, etc.

[Skirball]

Is there a reason you removed your EXIF data from the photos?

The shadow is too oddly shaped to be a lens hood, so you can rule that out.  It certainly looks like flash shadow, and all those look like they were shot with flash, any shadows on a non flash shot?   I think it's a safe bet that something is dangling in front of the flash.

Edit:  In response to 7D5D's edit - that's a good idea.  Set it up on a tripod or just a table, use the 2 second delay (or remote if you have one), flash on, and fire off a bunch of pics.  My guess is that you don't see shadows.