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Been getting these bubble type things, never happened before

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(Kit lens - 18-55|camera d3200

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  • \$\begingroup\$ Please describe "this" in words, both in the title (which will help direct people to your question) and in the question itself (so people can see what you're seeing). Thank you! \$\endgroup\$
    – mattdm
    Nov 1, 2015 at 17:52
  • \$\begingroup\$ dust on the sensor. \$\endgroup\$
    – Christian
    Nov 1, 2015 at 17:58
  • \$\begingroup\$ Those might be some oily smudges one your sensor. Are they present on other pictures ? If it is dust, it's in the lense (dust on the captor are much more in focus). Try with an other lens and take a picture at your smallest apperture (f22 ish) of a blue sky/blank sheet to detect what is it. \$\endgroup\$
    – Olivier
    Nov 1, 2015 at 18:30
  • \$\begingroup\$ You might want to read this post : photo.stackexchange.com/questions/12087/… \$\endgroup\$
    – Olivier
    Nov 1, 2015 at 18:34
  • \$\begingroup\$ Could be flare with all the point-light sources around, or could be dirt on the lens refracting unwanted/stray light, can you share other images which exhibit the problem as it will help us narrow down the options. \$\endgroup\$
    – James Snell
    Nov 1, 2015 at 20:04

3 Answers 3

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They look like smudges but far from the sensor. Check the back and front of the lens, plus BOTH sides of any filters you were using.

There are not sensor dust since they are two wide and blurry, plus sensor dust does not make anything brighter, they are usually dark spots on a bright background, not vice-versa as in your example. If they were some smudges from bad cleaning, for example, then they would be present on every image at the same exact spot, so you can do a quick test to confirm this.

They are positioned like flare, close to bright light sources but their shape are too undefined for it to be that alone. It is possible though that flare is aggravating the presence of smudges. In any case, cleaning of lenses and filters, if applicable, should be your priority.

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  • \$\begingroup\$ It takes a LOT on the front of a lens to be detectable in the resulting photo to that degree. See lensrentals.com/blog/2011/08/the-apocalypse-of-lens-dust \$\endgroup\$
    – Michael C
    Nov 1, 2015 at 21:00
  • \$\begingroup\$ @MichaelClark Yes, I know, I've referred to that article myself before :) Given the results, it could be just as it would take a whopping stain for sensor dust to look like that! \$\endgroup\$
    – Itai
    Nov 1, 2015 at 23:43
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These spots are a type of lens flare called “ghosting”. Light from the subject is supposed to transverse the lens and image on the surface of the image sensor. However, each lens has two polished surfaces that act to reflect away a small percentage of the imaging forming light. This happens many times as the camera’s optical system has many such polished surfaces. The bottom line is, some fraction of the imaging light rays commingle causing flare and ghosting.

We mitigate flare by coating the lens with a thin film of a mineral substance. The purpose of the lens coating is to reduce unwanted reflections from about 5% down to about 2%. Additionally we mitigate flare by not mounting a filter unless it does more good than harm. Glass filters over the lens add two or more polished surfaces. We mitigate flare by using a lens hood. These are funnel like devices that act like blinders to shield the camera lens from strong peripheral light from bright sources outside the camera’s view. These will promote ghosting unless shielded.

Flare and ghosting are devastating. Every optical system is plagued by flare. All we can do during composition is use a lens hood, avoid unneeded lens attachments and be watchful as we compose.

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  • \$\begingroup\$ If that is ghosting where are the primary light sources that caused the reflections that should be exactly reversed and inverted from the reflection? \$\endgroup\$
    – Michael C
    Nov 1, 2015 at 20:44
  • \$\begingroup\$ Each individual lens element in the system has a figure (curved shape). The internal reflections are numerous, each with a different angle of exit. Multiple reflections will not be exactly reversed and inverted. These defects are ghosting. \$\endgroup\$
    – Alan Marcus
    Nov 1, 2015 at 21:03
  • \$\begingroup\$ Other types of lens flare may not demonstrate this property, but ghosting, by definition, is a reversed and inverted reflection. Or at least it was when I took my first photography course several decades ago. It seems some folks now refer to aperture flare as "ghosting", but that is relatively new usage of the term, at least in my neck of the woods. \$\endgroup\$
    – Michael C
    Nov 1, 2015 at 22:51
  • \$\begingroup\$ I respectfully disagree that the spots in the example are any type of internal reflection. They are external in origin. I can easily reproduce the conditions that cause such spots. I've never seen an example of such spots that could be reproduced repeatedly strictly by the relative positions of light sources and a lens when both were in dry, clean air. \$\endgroup\$
    – Michael C
    Nov 1, 2015 at 22:54
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Your photo appears to have been taken from a car park. Most car parks have light poles evenly distributed throughout the entire lot, so there is the assumption that there are plenty of security lights to the sides and back of the camera. It also appears, from the star shaped light rays, to have been taken with a fairly narrow aperture.

This seems to be one of two things:

  • Light reflected off dust or moisture in the air in front of your camera. Some people refer to these type of spots as orbs. If there is a bright source of light (such as a camera mounted flash, which doesn't seem to be the case here) near the camera pointed in the same direction as the camera's optical axis then the light can bounce off of particles in the air. Since the reflection is normally a lot closer than the subject upon which the camera is focused, the reflected light is defocused and spreads out as it passes through the lens' elements.

  • Off-axis light from a peripheral source that strikes the front of the lens at a point where there is a refractive material, such as skin oil from a fingerprint, that refracts the off axis light enough to send it down the optical path of the lens. You will not see the actual fingerprint on the surface of the lens because it is too out of focus, but the shape and density of the oil that makes up the fingerprint can diffract off axis light into the lens' optical path.

My eye says it's probably the second scenario. Look and see if there are any fingerprints or other smudges of an oily substance on the front of your lens. But without knowing more about the shooting conditions we can't rule out the first scenario, especially if the air was very moist at the time.

Here's an answer that provides some helpful hints on how to reproduce these phenomena.

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