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what causes this blue outline?
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Oct 30, 2014 18:09:00   #
oldtigger Loc: Roanoke Virginia-USA
 
Sugar'sDaddy wrote:
I've noticed a blue outline on some of my bird pics when set against a blue sky .... What causes this, and what, if anything, can be done to prevent it. ...


high contrast transition point.
What does it look like in raw?

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Oct 30, 2014 18:21:35   #
LoneRangeFinder Loc: Left field
 
Bret wrote:
Dang and I haven't even had a beer yet...LOL


That was actually kinda cool. Yogi used to say stuff like that.

I knew a guy who would say "obedient light"... meaning, of course, ambient.



:thumbup:

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Oct 30, 2014 18:29:04   #
Elliern Loc: Myrtle Beach, SC
 
Linda From Maine wrote:
Chromatic Aberration :)


LOL. Yep that is it. But adoration sounds so much better.

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Oct 30, 2014 19:05:42   #
Sugar'sDaddy Loc: Hannibal, MO
 
oldtigger wrote:
high contrast transition point.
What does it look like in raw?


Sorry, I didn't shoot that one in RAW.

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Oct 30, 2014 19:16:09   #
mcveed Loc: Kelowna, British Columbia (between trips)
 
Sugar'sDaddy wrote:
No time like the present.
:lol:


http://photographylife.com/what-is-chromatic-aberration

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Oct 30, 2014 20:23:46   #
Sugar'sDaddy Loc: Hannibal, MO
 
mcveed wrote:
http://photographylife.com/what-is-chromatic-aberration

Thanks for the link. I've looked at it briefly and have a basic idea now, but I'm going back now to go over it again. It appears to me it can be corrected in pp if you have lens data, which I don't have any for the SX50. I'll do some searching for that info. Thanks again.
:)

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Oct 30, 2014 20:41:33   #
Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)
 
Sugar'sDaddy wrote:
I've noticed a blue outline on some of my bird pics when set against a blue sky (left side of woodpecker). Sometimes I get it, sometimes I don't. What causes this, and what, if anything, can be done to prevent it. Shot with SX50, f/7.1, 1/500sec., and ISO 160. As always, thank you for your help. Donnie


Chromatic aberration - blue, green or purple fringing at high contrast edges. Some lenses have it, some don't. If you use DXO, Lightroom/Adobe Camera Raw, they have built in lens profiles to correct for this. DXO's library of lens profiles is not as extensive as Adobe's, but they are of better quality. Best to shoot raw, and make the corrections before committing the image to raster format like Tiff, PSD or Jpg.

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Oct 30, 2014 21:12:02   #
SharpShooter Loc: NorCal
 
Sugar'sDaddy wrote:
Thanks for the link. I've looked at it briefly and have a basic idea now, but I'm going back now to go over it again. It appears to me it can be corrected in pp if you have lens data, which I don't have any for the SX50. I'll do some searching for that info. Thanks again.
:)


Sugar, let me give you the simple answer, rather than my usual smart a$$ answer! :lol:
The light rays can be separated into different colors rather easily and that shows up in our shots as color aberration.
The different colors of light, (wavelengths) travel at the same speed together. But as they go into the lens, the job of all those 13 elements is to focus the image(light) onto the sensor and to keep all the colors from separating. Since the elements have varying thicknesses for focusing purposes, the light takes longer to go through the different thicknesses of glass, because the glass creates drag on the wavelengths. So the ones that go through the glass elements slower or faster start to become separated and end up on your sensor as individual colors, or aberration. The job of all those elements is to keep them lined up OR to reassemble them into one color then onto the sensor.
That's why some lenses cost more than others. It's a fine balancing act between cost and IQ, of which aberration is one of the components of IQ.
Some types of glass are better at this than others, but that glass is very expensive, so you find more of it in very expensive lenses, and non at all in inexpensive lenses.
That's one of the reasons many pros will ONLY buy the best lenses, so they don't have to deal with those problems at all.
sugar, hope this was helpful. And if I'm way of base, hey, I went to public schools!! :lol: :lol:
SS

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Oct 30, 2014 21:29:36   #
Sugar'sDaddy Loc: Hannibal, MO
 
SharpShooter wrote:
Sugar, let me give you the simple answer, rather than my usual smart a$$ answer! :lol:
The light rays can be separated into different colors rather easily and that shows up in our shots as color aberration.
The different colors of light, (wavelengths) travel at the same speed together. But as they go into the lens, the job of all those 13 elements is to focus the image(light) onto the sensor and to keep all the colors from separating. Since the elements have varying thicknesses for focusing purposes, the light takes longer to go through the different thicknesses of glass, because the glass creates drag on the wavelengths. So the ones that go through the glass elements slower or faster start to become separated and end up on your sensor as individual colors, or aberration. The job of all those elements is to keep them lined up OR to reassemble them into one color then onto the sensor.
That's why some lenses cost more than others. It's a fine balancing act between cost and IQ, of which aberration is one of the components of IQ.
Some types of glass are better at this than others, but that glass is very expensive, so you find more of it in very expensive lenses, and non at all in inexpensive lenses.
That's one of the reasons many pros will ONLY buy the best lenses, so they don't have to deal with those problems at all.
sugar, hope this was helpful. And if I'm way of base, hey, I went to public schools!! :lol: :lol:
SS
Sugar, let me give you the simple answer, rather t... (show quote)

Thank SS. All knowledge is helpful. All I need is to apply it. And yes, I went to public school too. I'm getting the feeling that I will have to live with this problem as long as I use the SX50, or I think, or feel, a GAS attack coming on, maybe a dslr+glass.

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Oct 30, 2014 22:49:18   #
Nikon_DonB Loc: Chicago
 
SharpShooter wrote:
Sugar, let me give you the simple answer, rather than my usual smart a$$ answer! :lol:
The light rays can be separated into different colors rather easily and that shows up in our shots as color aberration.
The different colors of light, (wavelengths) travel at the same speed together. But as they go into the lens, the job of all those 13 elements is to focus the image(light) onto the sensor and to keep all the colors from separating. Since the elements have varying thicknesses for focusing purposes, the light takes longer to go through the different thicknesses of glass, because the glass creates drag on the wavelengths. So the ones that go through the glass elements slower or faster start to become separated and end up on your sensor as individual colors, or aberration. The job of all those elements is to keep them lined up OR to reassemble them into one color then onto the sensor.
That's why some lenses cost more than others. It's a fine balancing act between cost and IQ, of which aberration is one of the components of IQ.
Some types of glass are better at this than others, but that glass is very expensive, so you find more of it in very expensive lenses, and non at all in inexpensive lenses.
That's one of the reasons many pros will ONLY buy the best lenses, so they don't have to deal with those problems at all.
sugar, hope this was helpful. And if I'm way of base, hey, I went to public schools!! :lol: :lol:
SS
Sugar, let me give you the simple answer, rather t... (show quote)


Great explanation SS. Even I understood that and I didn't go to public school. Awesome! I learned something. Thanks.

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Oct 31, 2014 07:34:02   #
Shakey Loc: Traveling again to Norway and other places.
 
If you want to learn how to hide the effects of Chromatic Aberration follow this link: http://www.uglyhedgehog.com/t-69708-2.html#top
The software used is GIMP but you can probably use the same technique with most software. In the tutorial I've used grey but a little thought and maybe you can use a color of your choice.

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Oct 31, 2014 07:44:22   #
infocus Loc: Australia
 
Sugar'sDaddy wrote:
No pp except for cropping.


Look at what Bret suggested but Linda spelled correctly. That's you answer. :thumbup: :D

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Oct 31, 2014 07:52:57   #
dpullum Loc: Tampa Florida
 
Point out to people that it is a lensing effect of the fine structure of the bird feathers. An effect very similar to a diffraction grading used in crystal analysis and that only the finest of camera equipment is capable of recording it.

You may think I am joking.. which I am, but it is real...
http://ww2010.atmos.uiuc.edu/%28Gh%29/guides/mtr/opt/mch/diff.rxml

Does a humming bird have color... Nope does not....
http://www3.nd.edu/~amoukasi/CBE30361/Useful%20files/Interference%20of%20Light%20Waves.pdf

What a strange world we live in !!!

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Oct 31, 2014 09:49:18   #
dennis2146 Loc: Eastern Idaho
 
Bret wrote:
Dang and I haven't even had a beer yet...LOL


Maybe that is the problem, Bret. Maybe your body is telling you to have one. I had Chromatic Adoration once but it dumped me. That is the way my life usually goes.

Dennis

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Oct 31, 2014 10:21:57   #
Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)
 
SharpShooter wrote:
Sugar, let me give you the simple answer, rather than my usual smart a$$ answer! :lol:
The light rays can be separated into different colors rather easily and that shows up in our shots as color aberration.
The different colors of light, (wavelengths) travel at the same speed together. But as they go into the lens, the job of all those 13 elements is to focus the image(light) onto the sensor and to keep all the colors from separating. Since the elements have varying thicknesses for focusing purposes, the light takes longer to go through the different thicknesses of glass, because the glass creates drag on the wavelengths. So the ones that go through the glass elements slower or faster start to become separated and end up on your sensor as individual colors, or aberration. The job of all those elements is to keep them lined up OR to reassemble them into one color then onto the sensor.
That's why some lenses cost more than others. It's a fine balancing act between cost and IQ, of which aberration is one of the components of IQ.
Some types of glass are better at this than others, but that glass is very expensive, so you find more of it in very expensive lenses, and non at all in inexpensive lenses.
That's one of the reasons many pros will ONLY buy the best lenses, so they don't have to deal with those problems at all.
sugar, hope this was helpful. And if I'm way of base, hey, I went to public schools!! :lol: :lol:
SS
Sugar, let me give you the simple answer, rather t... (show quote)


At first what you wrote made little sense, the speed of light is a constant - but after considering how it behaves in different materials, especially those that diffuse light, even though the speed is a constant, it can take longer for light to get through a diffuse material, because photons get scattered all over the place, so they are bouncing off of other atomic particles before they eventually reach their destination. I learned something today - thanks!

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