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Visible spectrum in a photography


Ityrus

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Hello, I'm new here. smile.png

 

Yesterday I was on my bed taking some photographs of the lamp on the ceiling, with my Motorola EX130 mobile phone.

 

The strange thing I noticed was that bringing the mobile in a certain inclination and position, before taking the photo, I could see all the colors of the visible spectrum around the fuzzy white halo which I'd already seen every time. In fact, now that I took the photo, the effect always arises again when I rotate my mobile by about 45°.

 

Now I'm asking me, who haven't already studied optics (but I'm going to start next month): why did the different parts of the visible spectrum place themselves around the white halo of the lamp? And why have I found this behaviour only with my mobile, and not with my camera, which is much more sophisticated? confused.gif

Edited by Ityrus
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There are a few things which it could be, I'd heal a pay dnigrm to work it out more closely. so light salts are difbnt with a wavelength dependence. So you have chromatic aberration, the thin film effect and grating effects. If you read about three you'll understand most of the physics that's likely involved.

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The simple answer iis that your camera lens is made to tighter tolerances than the phone lens.with respect to controlling chromatic aberration which is where not all the frequencies are not equally focussed on a single axis. Like this:

 

Longitudinal-Chromatic-Aberration.png

 

This is a perfect lens:

 

Corrected-Chromatic-Aberration.png

 

Lenses, on the whole, get worse for correction towards the edges and the challenge (and cost) is maintaining image consistency across the whole lens surface. The chromatic aberration effect is very noticeable here...note how the colour is neutral at the centre:

 

Focus-Accuracy-AF-Fine-Tune-2.jpg

 

The images were acquired from this nice article here: http://photographylife.com/what-is-chromatic-aberration

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StringJunky, you're right. smile.png

 

Just I took several photos, and really I don't understand well which of them have longitudinal aberration and which one have lateral aberration.

 

In fact, if you take a look at the two images in attachement, you'll find that in one of them the color ring that was created around the halo of the lamp is formed only of the colors red and orange, while the other's got all the spectrum.

 

Oh, and remember to rotate your monitor when trying to detect the aberrations. wink.png

post-90566-0-62352400-1367081035_thumb.jpg

post-90566-0-28005400-1367081046_thumb.jpg

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