[Becco_UK]

This post carries on from someone elses post concerning prism effects.

The dispersion gradient colours produced by Maxwell Render do not appear to be physically correct, particularly down in the purple region.



There seems to be lots of pinky coloured purple which sort of looks strange (hope Tom don't mind about using this image!).



This image (taken August, 2003) is a naturally occurring gradient being cast by sunlight through a crystal object.

One photo doesn't make much of a case for change so this morning using another crystal object I took another photo:



In the United Kingdom we don't seem to get all that garish pink in spectum colours!

I feel Next Limit should adjust the colour gradient so that it produces accurate results, not just pretty results.

[Thomas An.]

http://www.fas.harvard.edu/~scdiroff/ld ... ctrum.html

[Thomas An.]

Reality looks too much RGB to me.

Maxwell is better

[Thomas An.]

http://www.kgg.org.uk/spectrumh.html

Spectrum of a 40W spotlight

[Thomas An.]

I think this is the best presentation of prismatic dispertion
http://www.rit.edu/~andpph/exhibit-spectrum.html

Light dispersion by prism #6185b


Images (c) Andrew Davidhazy

[Becco_UK]

Thomas An.: Those links you posted look very useful. Most of the images at the links do not show the light pinky tinted purple.

It seems Maxwell Render is using a make it pretty gradient.

In naturaly occuring spectral dispersion I have not seen the light pinky purple colour.

To me, the most eye catching of all dispersions is the rainbow.

[Aldaryn]

There is some pinkish purple in this spectrum.

[tom]

all right, you know it's depending on light source.... you can have all or some...

[v.montel]

Hello Maxwellians.
My first post here since I only own Maxwell from beta release, but have been following lot of wips and discussions here though.

My 2 cents for this thread : one must keep in mind that if we don't see this so called "purple" area in most real spectrums, is maybe because we CAN'T see it. As for very low range in these same spectrums (like low red), this part of light is actually the non "seeable" part of the white light spectrum, which matches with the two ranges we can't see by naked eye in reality, I mean infrared and ultraviolet.

This statement taken into account, it would meen that the difference and "mistake" with MW renderings is that it lets you see these two invisible parts of the spectrum.

[Becco_UK]

tom: Yes, it is sensible that the spectrum colour would change appearence according to the light source being used.

Do you know if Maxwell Render takes this into account or is the gradient a fixed one.

If it is fixed then do you please also know what light source type Next Limit chose to make the gradient.

I am interested how the colour of the present Maxwell Render gradient came about.

[tom]

dispersion has still some way to go and you'll find the answers in the following days...

[n1tram]

Tom, is this related to the Dots in anyway?

[tom]

since everything has relation with each other,
i can't say this is totally apart from other issues,
so it'd be better to see why when it's all right.
i can try to explain the actual things but not
the forthcoming things...