Shutter!

[Chang_paarp]

The first 2 images would be called back scatter if taken underwater. Where the flash is reflected by stuff suspended in the water.

I am guessing that it is the same thing, just not in water, water drops or spray and dust particles. Not as interesting as a supernatural idea, but but about as hard to photograph when you want to. They seem only to appear when you want them least.

[britmaveric]

Looked through some of my cave shots - I only caught two of the round objects in one photo. Mind if I saw smth like what you posted prob would have trashed it.

[ourmanflint]

almost certainly moisture on the lens, it's a very regular pattern, and I don't think ghosts perform in unison...

[Girlfrombar]

phewwww... not as haunting as i thought

but at least i dont have to look behind my back eeeiiww!

[Nordlys]

I would if I were you.

...............kidding.

[Carmine6]

I found out by accident how to create shots like this. What you have to do is get your finger or something else like a strap partially over the flash so that some of the light is either coming back towards the lens or sideways rather than out. Ghosts galore if you get it right. Try it at night yourself. You can try completely clear ones and partly covered ones and you'll get a big difference.

Anywhere there's water spray or dust in the air is a guaranteed bonanza. Condensation on the lens can do something similar.

[marktomaras]

Well, due to the nature of the little circle shapes we are talking about, this is certianly not a noise issue. noise is always evenly distributed across the image, as the circumstances that cause excess noise apply to the entire imaging sensor. That said, noise is generally more visible in the shaddows, but it is also present in the other areas.

Have you ever seen a shot taken in the snowing outdoors with a flash? the flash pops and all those white falling objects reflect a lot of light making the snow have much more presence than it does in reality.

This is what I think happened in your cave. If the cave was dark and the flash was on (which looks clear to me) that means the flash would have fired at full power to attempt to fill in all that darkness. If the cave had a lot of moisture in the air, and a bunch of particles to boot, this could be the "snow" effect in the cave.

Now, I wont bet my life on this, but I'll surely lay down 500 baht on my theory!