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Old Jan 15, 2012, 9:58 PM   #1
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Default Lens Light Flare

While I know what causes lens flare (light bouncing around in a lens where it shouldn't), are there some types of lenses that are more prone to it than others? I've seen it with the DA*50-135 and I thought perhaps a zoom lens was more prone to it than a prime. However this morning I found a relatively wide angle prime has some, too. It seemed to get better when I stopped the lens down (smaller opening, light path is straighter and so there's not as much light bouncing around) but even at f14, there's still a fair amount. Here's the picture, only slightly cropped (really like the picture by the way):



Here's a 100% crop. It's interesting to see the displacement, this is from the right side of the picture. The left side has the displacement to the left of the light fixture.



So is there a way to avoid this type of lens flare? What lenses are more likely to suffer from it?
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Old Jan 16, 2012, 5:54 AM   #2
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I don't think that the 'starburst effect' is really considered unwanted flare (though I may be wrong - as I often am !) and it is actually sort after by some and many people (including me) love the fantastic DA15 Ltd, and also the DA21 Ltd, specifically because both exhibit superb starburst effects. I may again be wrong but I believe that has as much to do with the coatings as it does the lens ?

The unwanted flare that is exhibited in many lenses in strong sunlight (usually as a washed out streak of colours or patch) is usually the result of the camera being within a specific range of the angle of incidence of the sun to the camera (I believe somewhere around 45 degrees is the trouble spot).

Not sure if a polarising filter would reduce the (positive) flare exhibited above or not.

Your shot above would make a gorgeous panorama after trimming !
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Old Jan 16, 2012, 7:09 AM   #3
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Wild guess. Use a slower shutter speed?
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Old Jan 16, 2012, 7:58 AM   #4
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Hi Harriet

I agree with Kevin, that isn't lens flare but a starburst effect. I always thought that flare was either unwanted "streaks" of light or those pesky - ummmm, how to describe them - blobs(?) of light.

I cheated and had a quick look on the net and one site http://www.lightstalking.com/starburst-effect suggests that the starbusrt effect is caused by the aperture blades and increases with a smaller aperture. Also, like Kevin, I wondered about a polarising filter.

What I can say for definite is that I really love that photo and for me, the starburst effect enhances the picture.
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Old Jan 16, 2012, 8:01 AM   #5
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Don't change a thing-looks great with the star effect.
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Old Jan 16, 2012, 9:53 AM   #6
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I should have explained better in my original post - I'm not talking about the starburst effect that this picture shows very nicely. That's the reason why I used an aperture of f14 with a lens most often used at f5.6 or larger, I was aiming for the starburst effect. However, if you look at the crop, you'll see on the right side that there's a smaller light blob to the right of the star burst. As you get closer to the left side of the crop (center of the picture) the blob is less displaced. If you look at the full frame version, you can see the blob on the left side of the picture is displaced on the left side of the light.

I've seen the same sort of displaced bright light when using the 50-135, only it's worse because the distorted blobs are displaced further away and can be really distorted into weird sizes. At least with the picture above it isn't really strange and others don't seem to notice it.
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Old Jan 16, 2012, 11:48 AM   #7
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Those blobs don't look anything like flare to me Harriet .... I'd proffer a wild guess that they are in fact very dim, slightly more distant (other side of the pier ?), light sources that have been enhanced by a 'longish' exposure. That guess may even be more accurate on second glance as all three appear to be at the same height.
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Old Jan 16, 2012, 12:20 PM   #8
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I believe Harriet is correct the 3 hollow lights at the extreme right of the crop look like flair to me, they are slightly above the source and have a dark center.

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Old Jan 16, 2012, 1:43 PM   #9
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Aha, now I see them!!!

Should have known that you knew the difference between flare and starburst - sorry!

I had mistaken them for lights in the background.But looking closely I can see they're not. Also, unless I am mistaken, the brightness of the 3 most obvious diminishes as you move right to left (100% crop). To my old eyes, it also looks like these artefacts move closer to the light source the further from the right you go! If that is the case it does suggest that it might have something to do with it being a wide angle lens (is a 31mm classed as a wide angle?). It would be interesting to see a 100% crop of the left side as well (and the middle).

Must admit I've never noticed anything similar when I've taken that sort of shot. But I tend to use a longer focal length; perhaps the longer the lens the less flare.

Still a fab shot!
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Old Jan 16, 2012, 3:13 PM   #10
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A simpler lens has less elements so it is usually less susceptible to lens flare. This would mean primes over zooms. Lenses with better coatings are much less susceptible to lens flare, for example SMC. This brings the reflections down to about some like .2% from 5-6%. Some say that the Zeiss T* coating is a little better then the Pentax SMC like maybe .1%. The best coatings available are said to be the new ghost coatings by Pentax. A rumor is that an early version of this coating is on some of the FA limited (like a FA 43) lenses. The story goes that Pentax developed this coating for traffic cameras in Japan. The only lens that I know for sure that has this new coating is the DA*55. It is called the Aero Bright Coating. This coating is probably at or very near the limit of what it is possible in optics.


As you are already using about the best lens for this about the only other lens would be the DA* 55 but you are pushing the contrast so high (light against black) that you are pushing up against the DR limits of lenses. What I mean with the last part is that as you put more light into the front of a lens you are reaching the limits of the DR of the lens. It can only have so much contrast between a light part and a dark part before the optical flaws limit the DR of the lens. Past this limit the only solution is PPing.


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