So I've been noticing a lot of lens flare on pictures I've been taking. Especially there is a light source that is LED. Seems to happen on both my phone and Sony. Anyone else have this issue or know of how to reduce or eliminate it?
Funny, most people are looking to add more lens flare as an effect. In television cameras the fewer physical elements in a lens increase the chance of accidental flare, or more specifically the flare has a better chance of dissipating as it passes through more elements. Although not my field of expertise, I suspect this also applies to still cameras. To make today's cameras and phones lighter and cheaper they probably use fewer but more refined elements. I also believe the comment about LED's above is correct, and that sustained LED light is created by a combination of increasing the frequency of these pulses, coupled with multiple units that offset each other to maintain a constant level. It is reasonable to think this could impair a photograph.
Photoshop (and its competitors) are about the only way to remove a flare. I believe there is an online video on how to do exactly this.
As Jiml alluded to above, the quality of the glass and its coatings makes major differences in the tendency to create lens flare. Lenses with really good glass and coatings start at about $800 and go up from there.
Some photographers actually prefer to get some lens flare in their images. But, in my opinion, as strictly an amateur photographer, keeping more than 1% of photos with significant lens flare is 'too much'. Sometimes, Photoshop can be used to remove or at least minimize some of the lens flare. But the issue is that the image itself is 'washed out' in the lens flare area making restoration difficult.
Perhaps the biggest cause of lens flare is light entering the lens at an 'oddball' angle other than within, say, 30-40 degrees of the centerline of the lens. Consider a night scene looking down a street with street lights as well as signs, etc. A street light 100' in front of the photographer and at 2 o'clock from the centerline of the lens, will likely produce lens flare in even the best of lenses. One of the best solutions to reduce the occurrences of lens flare is to use a lens hood designed for that lens. When shooting with my phone or compact camera, I've been known to put my cupped left hand over the front of the camera to prevent the sun or other bright lights from entering the lens at oddball angles. Note, too, that lens flare, like back lit scenes, almost always 'fool' the camera metering system resulting in an underexposed image that needs to be 'brightened up' in Photoshop, Lightroom, or other image editing software.
LEDs don't pulsate when fed by pure DC. However, they will pulse when fed by AC. Many LED systems use a switching power supply with a poorly filtered output, or vary the frequency (hence duty cycle) to create dimming.
This pulsing which, combined by the scan rate of the photodetector in the camera, can cause flicker in a motion picture, confusing the automatic exposure or brightness circuitry. This is kindasorta similar to the stroboscopic effect we see when spinning objects appear to be slower or even reversed direction. Google "stroboscope".
Try turning off automatic exposure, you might see some change re the hazing.
There is another effect I will research. The particular wavelength of the blue LEDs used in emergency vehicle light bars creates an odd diffused effect when shot by our newsgathering cameras. Hard to describe, but rather than a pinpoint of light, there is this odd glow or halo only created by blue LED sources, never the strobe lights.
Look at the blue and the green LED lights in the trees in seat38a's shot above. See the odd blue smearing? Only the blue and to a lesser effect the green LED's do that. (In electronic photography, Red, Blue and Green are the primary colors. There's a lesson in there somewhere).
I'm gonna look into this next time I get a camera in the shop. May be some prismatic or other chromatic effect in the color separation process of the camera sensor. Ultraviolet may be involved as well.
Those are really nice photos, by the way, thanks for posting.
Class dismissed, time to make the donuts...