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Enjoying Chromatic aberration?

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#1 drt3d

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Posted 17 January 2022 - 08:05 PM

I saw this posted on facebook yesterday. Thoughts?

 

271655924_604697343957727_2037629534580217838_n.jpg


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#2 Rich V.

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Posted 17 January 2022 - 08:15 PM

Maybe looking at rainbows gets them wondering, too.   wink.gif   Sounds like a magical experience.


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#3 DeanD

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Posted 17 January 2022 - 08:19 PM

What replies did they get? Did anyone explain properly, or did they simply share their ignorance?  ;)



#4 dries1

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Posted 17 January 2022 - 08:21 PM

I wonder what the responses will be, if there are any. I have no idea since I don't have facebook.


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#5 drt3d

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Posted 17 January 2022 - 08:39 PM

Hi guys,

Yes, it was explained very clearly that he is describing chromatic aberration, which is basically an optical defect, more pronounced in less expensive binoculars. I personally said that I have paid a lot of money so I do not see any blue and yellow colors on the moon.

 

This was an interesting response: ""poor" is a matter of opinion here. It's because of the way light refracts through a lens. For many folks, they want a pure image with no light diffraction. and that's awesome. But it's also enjoyable and educational to consider light refraction and why it happens. It's just a thing that happens."

 

Anyway, the person asking the question said that he understood the situation, still likes the effect, and maybe one day he will get a better pair of binoculars.

 

I just thought it was interesting that there are people out there enjoying seeing these colors on the moon, which is something that I personally do not like at all :)

 

George


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#6 dries1

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Posted 17 January 2022 - 08:45 PM

If they stare at it long enough they will grow to dislike it.


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#7 TOMDEY

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Posted 17 January 2022 - 08:51 PM

I can only conclude that the originator has earned Ivy league Ph.D.'s in both Photonics and Philosophy. I've worked with these types most of my career. Let's just say they come from ~a different place".    Tom


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#8 drt3d

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Posted 17 January 2022 - 09:07 PM

There seems to be a variation in people's tolerance for chromatic aberration. Some people (I am one of them) cannot stand it, others either do not mind it or even do not notice it. I wish I did not care. Unfortunately, I do, and it bugs me when I see it.

 

I am also a photographer and you can see chromatic aberration is some long focal length lenses. When you see it, you know that it is only the colors but also the sharpness of the image is compromised. I am also into 3D photography and I use viewers to view 3D images. Some viewers have single element lenses or designs where the chromatic aberration is pronounced. The better viewers have achromatic lenses and you do not see any chromatic aberration. I am amazed that not everyone sees or is bothered by the chromatic aberration in single element lenses.

 

George


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#9 ECP M42

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Posted 17 January 2022 - 09:45 PM

In general, I don't particularly mind the CA. If I look for it I always find it, but I never look for it while I observe normally.
So, yes, it's a very subjective optical aberration, like the curvature of the field (for example). And I'm sure we could all list the most acceptable and the most unbearable aberrations.

Lateral CA is more "sympathetic" to me (so to speak), most likely due to the colors it disperses (yellow and blue) in the achromatics and the fact that it is usually absent in the center of the field.
On the contrary, I don't like longitudinal CA, but mostly because of the colors that are typically dispersed (magenta and green).
I don't know why, but the purple / magenta fringes bother me a lot in the images (be it videos, photos or eyepieces). And the contrast with the typical green becomes even worse (psychologically).
Triplet (apochromatic) optics generally "spread" different and more acceptable colors to me.
But for example, when I first looked at the starry sky with the Deluxe 10x50, I noticed a good deal of lateral CA lateral painting all the brightest stars. And with the summer turbulence, those binoculars created a kaleidoscope of "moving" color, which I thought was fun.


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#10 ihf

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Posted 18 January 2022 - 01:40 AM

Driving west this afternoon I saw sun dogs left and right of the setting sun. I always enjoy them.

I once compared spotting scopes. A small achromat Minox at 40x showed the most mesmerizing disco ball on an out of focus star.

In optics I had a strong emotional aversion against chromatic aberations. But I think I can control the emotion now. Everything is a tradeoff.


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#11 Mark9473

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Posted 18 January 2022 - 03:14 AM

Blue and yellow halves isn't chromatic aberration but rather atmospheric dispersion.
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#12 Baobas3360

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Posted 18 January 2022 - 04:55 AM

Chromatic aberration will always be present in fast binoculars, even if they are of high quality,where the quantity of chroma will be less. As the lens diameter increases, the optimal focal length may be too large for practical use and has a non-linear dependence.Starting from a certain aperture, such a device will be too long. I personally like the yellow edging of the image more than the blue



#13 DrJ1

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Posted 18 January 2022 - 09:08 AM

Hi guys,

Yes, it was explained very clearly that he is describing chromatic aberration, which is basically an optical defect, more pronounced in less expensive binoculars. I personally said that I have paid a lot of money so I do not see any blue and yellow colors on the moon.

 

This was an interesting response: ""poor" is a matter of opinion here. It's because of the way light refracts through a lens. For many folks, they want a pure image with no light diffraction. and that's awesome. But it's also enjoyable and educational to consider light refraction and why it happens. It's just a thing that happens."

 

Anyway, the person asking the question said that he understood the situation, still likes the effect, and maybe one day he will get a better pair of binoculars.

 

I just thought it was interesting that there are people out there enjoying seeing these colors on the moon, which is something that I personally do not like at all smile.gif

 

George

I enjoy seeing purple branches on trees against the white snow backgroundshocked.gif



#14 Corcaroli78

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Posted 18 January 2022 - 09:21 AM

The first time i pointed my telescope (a 50/400) to the Moon, i was shocked by the colorful image, i was proud to see so beautiful image so i called all my family to the roof to share the experience.

 

Of course, with the time i have learned about optics and as some stated before, and if not avoidable in binos and RFT scopes, I prefer yellow than violet in the Moon edge.  

 

Carlos



#15 sonny.barile

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Posted 18 January 2022 - 10:13 AM

Blue and yellow halves isn't chromatic aberration but rather atmospheric dispersion.

Ha….thanks,  I learned something new.


Edited by sonny.barile, 18 January 2022 - 10:13 AM.


#16 sonny.barile

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Posted 18 January 2022 - 10:15 AM

I can not tolerate CA or hard vignetting. Both will drive me insane. I do not see colors correctly so it may be more annoying to me than most. I can tolerate a little bit of warming as is the view in lesser quality ED glass. When vignetting is visible I’m out……If I see it that equipment combination will never happen again. 
 

When I wanted a BT I waited until I could afford SD optics and selected my eyepieces with vignetting in mind. Nothing else drives me that crazy………even poor field flatness wouldnt put me off to much. Narrow fields are not comfortable but still not enough to ward me off. 


Edited by sonny.barile, 18 January 2022 - 12:47 PM.

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#17 drt3d

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Posted 18 January 2022 - 11:52 AM

Blue and yellow halves isn't chromatic aberration but rather atmospheric dispersion.

 

I do not understand this. Can you explain it? 

 

Looking at the moon with some binoculars I see blue and yellow edges, I assume it is chromatic aberration because I do not see these colors with good binoculars. Shouldn't atmospheric dispersion be visible with all binoculars? Is it the name of the colors that is different? (magenta or something else?)

 

George



#18 Mark9473

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Posted 18 January 2022 - 12:12 PM

Well, what I'm referring to is when the Moon or a planet isn't very high above the horizon, atmospheric dispersion causes the top half of the object to have a blue edge and the bottom half orange.

What I don't know is if you're experiencing something else related to off-axis chromatic aberration in the eyepiece, and the Moon being placed off-center?
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#19 Senex Bibax

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Posted 18 January 2022 - 12:21 PM

Here's the perfect pair for those who "like" CA:
https://www.blocket....ainbow/99075711

I can translate, but the pictures tell the story.



#20 ECP M42

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Posted 18 January 2022 - 11:21 PM

Chromatic aberration will always be present in fast binoculars ... I personally like the yellow edging of the image more than the blue

The colors I see (such as lateral CA) are generally more than two (blue and yellow), sometimes there is also red (for example) and the various shades between these three main ones, such as indigo, yellow- light green (green only hinted at) and red-orange.
Deep dark blue (not light blue) is a color that I really like. It is the typical color of the nautical twilight sky and is complementary to the bright yellow of the Sun.

 

There is no limit to the subjectivity of colors ... smirk.gif  




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