Camera flash cause bright "disks" in the image

[Hajk]

Hi, I'm not a professional photographer but I was just wondering why the below photo which was taken with a flash have several "orbs" scattered over the image (sorry for not having a larger picture).





Thanks

[Mike]

Thode 'disks' are instances of what is commonly known as 'lens fare'. Lens flare is caused by stray light entering the lens - the photo is of a caving expedition? The front of the lens may have had dust or (more likely) droplets of water on it which has caused the light to flare in that manner.

[OdiN1701]

Looks like you've found some ghosts.

[20droger]

"Orbs" it is! Magical mystery creatures caused by out-of-focus dust brightly lit by the flash. These are most often invisible specks floating in the air, rather than specks on the lens itself. They are close to the camera, and therefore very brightly lit by flash set for proper exposure of a more distant object. The brightness of the specks is a result of the fact that the light from a flash falls off as the square of the distance, in both directions!

Spirit believers typically claim these orbs are proof of ghosts. What they really are is proof of dirty air.

[iamaelephant]

http://connect.afi.com/images/content/photos/large_12789.jpg

[rdenney]

Always, always, always use an effective lens shade when using a flash. The flash must never illuminate the front of the lens. Even if the lens had water drops on it (which I agree is probably the issue here), you would not have seen them if they were shaded from the flash.

Rick "who has a lens shade--sometimes a really expensive one--for every lens he owns" Denney

[20droger]

Oh, yes! That reminds me! Be careful not to get slimed while capturing orbs!

[Jon]

It's more likely dust or other particles in the air than on the lens. A hood won't help with that. The bigger the spots the closer they are to the lens.

[kniteshade]

Given the rocks and head-lamp on the guy, I'm guessing it may have been taken in some kind of cave or mine. I imagine its moisture on the lens due to the excessive humidity

I got the same thing on all my photos when I got to go 1000m underground at a goldmine (and the place is almost flooded with water to reduce dust). Also saw them on a friends recent photos from within Tombs in Egypt.

[20droger]

Orbs are a common and well-researched phenomenon.

To show up as orbs, dust or moisture on the lens would have to be illuminated by the flash. This would require the flash to be ahead of the lens and aimed so that the lens surface is illuminated during the flash. This is rarely the case.

Orbs are almost always caused by dust or moisture in the air a few inches in front of the lens. Orbs are also more often caught by in-camera flash, in contrasted with on-camera or off-camera flash, as in-camera flash is very close to the sight line and easily illuminates close particles.

You can easily create your own orbs on demand by shooting in the rain, or by blowing dust or moisture in front of the lens at the time of the flash.

Dust orbs are typically white, and often show diffraction rings. Moisture (water droplet) orbs sometimes show colors, either as linear bands or colored diffraction rings, due to the prism effect. This is the same effect that makes rainbows appear always opposite the sun.

Non-aqueous liquid particles (oil droplets, etc.) will often produce extremely strange colored effects.

With slow or strobed flashes, orbs sometimes take on bizarre shapes.

Orbs may also be seen in underwater flash photography, where they are reflections from particles or near microscopic life forms in the water.

[Hajk]

Wow thanks for all the great answers.

Just a follow up question: why does these "orbs" have diffraction rings around them? shouldn't the flash light just reflect on the dust/water drops and go back in the camera lens creating a simple orb without any rings around it? where does the diffraction occur?

Thanks

[20droger]

They have diffraction rings because the dust or moisture particles are so small. Their size produces standing waves, which interract to produce the rings.

This gets into the wave theory of optics, which is a rather complex subject. The very small particles in some ways act like very small pinholes or slits. The reflected wave then interracts with the edges of the aperture to produce the inteference that is realized as diffraction rings.

In essence, it is the same phenomenon that causes images to go soft at very small apertures, only the smallnes, in this case, is in the particles themselves.

[ovjamaica]

20droger is absolutely right. These are just "orbs" caused by dust or moisture in the air. I work at a theater that many claim to be haunted, and "ghost hunters" have come in and gotten pictures of these mystical "orbs". But, like 20droger said, it's easy to reproduce and thus discredit the "ghost" connection.

On a related note, these "orbs" only work in the digital world. I've never seen one produced with a film camera.

[20droger]

Actually, they work fine in the film world, but only with cheap cameras with close-to-the-lens in-camera flash. Moving the flash away from the line of sight, even by using an on-shoe flash, increases the distance from the lens that the flash will be able to illuminate airborne particles. To produce orbs, the particles must be close to the lens. The farther away they are, the less likely it is that orbs will be produced. After a foot or two, particles will not produce noticable orbs.

You can prove this to yourself with a cheap disposable film camera with a built-in flash unit.

[neumanns]

Insects can also cause them.

I had a shot last week where you could see the size decrease as they got closer to the focal plane.

They went progresivly smaller till you could actually tell they were insects.

I went and looked for the shot but since they ruined the shot I was after it got trashcanned.

However here is one shot that there is one large OOF bug and you can see the swarm in the distance behind it

[doidinho]

What lens are you using? Is there dust in your lens?

[neumanns]

That's a 70-200 2.8 IS...No it's clean!

Flash was a sigma 500dg on hotshoe.

They showed up in several shots...You could definatly see an insect hatch going on in the photo's.

[20droger]

Dust, droplets, gnats, anything very small can produce orbs. All that is required are "particles" close to the lens and a flash close to the sight line.

In the porcupine picture, it appears there is a gnat swarm normally lit, with one moderately close gnat as an orb.