ETAS

[AV_]

@Serg, related to a recent post of yours:

... the page https://docs.cutwise.com/blog/ray-path-in-round-diamond touches 2 very important issues for diamond optical performance
1) Stereo rivalry :
Red +Red combination does not mean best Brilliancy.
Sometimes Red+White creates better Brilliancy.
2) VF's angular speed ( for main facet it strongly depends from pavilion angle.Main facet with shallow angles have much less angular speed compare with facet for Pavilion angle 41.8( I am not saying that Cr34.5 P41.8 is good or bad diamond. I am telling about angular speed which has high correlation with diamond "Life"). The Shallow diamonds could have high Light return but it have weak " Life."
Deep diamonds could have less Light return, but much bigger and attractive "Liffe"

I would propose to use superposed ETAS of several positions of the stone, instead of combinations of reflector images [into a muddle] - the ETAS graphics add up naturally. I find the exercise beautiful enough to want to put some work in a little experiment to write about [if easy enough to do!] - would wish to map the contrast brilliance of a couple of beautiful, extremely different cuts; eg the demo of crownless step cuts of YF comes to mind; I have not made up my mind on other cases yet, TBD!

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If anyone might wonder where this odd idea comes from [other than admiring ETAS!], I have a playful end in mind:

I suspect I have a certain way of seeing 'brighteness', exagerating contrast - certainly not obvious IRL, except in choosing diamonds & styles of painting & other beloved graphic arts. Quite likely, I would have this mannerism of perception 'taste' all my life, if it wasn't for the talk of contrast & ETAS & brilliance/brighteness/fire here. Of course, I am curios to dig a little into such inclinations or tastes for contrast patterns, along the lines above mentioned.

 

[tyty333]

ETAS???

 

[Serg]

ETAS???

5. ETAS - part of space visible through moving diamond

 

[AV_]

@Serg Thanks! Will followup by email one of these days.

 

[cflutist]

ETAS???

Examples can be found here:

An improved HPD Trilogie with 2.18 E-VS1 center

@Dancing Fire What do you think? Old with 2.21 F-SI1 55.7% table 15.1% CH New 2.18 E-VS1 with 54.2% table 15.7% CH IDK. I don't have them in front of me. :bigsmile:

www.pricescope.com