John Q., follow up question on Princess Aset.

[Ellen]

Hey John,

I am typing this here, as it just takes me too long in the webinars. My keyboard sticks, so I either type fast and then can''t see the mistakes, or I type slow and lose the subject. Plus, it might benefit someone else.


I asked about "a lot" of blue being good. First, I knew in my head what I meant, but it sounded wrong when asked. Of course you don''t want tons, but a decent amount, which I''ll post a stone I think has.

I understand what should be black in a round, and that some can be missing and the stone will still be pretty, just not as pretty as it would with more.

What I''m trying to understand with Princess, which I confess I know little about (that''s why I''m asking

), is just how much is just right, and when it it too much, or too little?


This one seems to have a decent amount, or, is it too much? (I doubt it)
http://www.whiteflash.com/aca_princess/A-Cut-Above-Princess-cut-diamond-174064.htm#


This one has a lot less, or, is it just right?
http://www.whiteflash.com/aca_princess/A-Cut-Above-Princess-cut-diamond-45612.htm#

I realize you may very well say both will be beautiful, and either amount is good, I just need a guideline.


I know you''re quite busy at the moment, so take your time answering, no biggie.

TIA!

 

[WinkHPD]

Date: 1/27/2007 3:39:48 PM
Author:Ellen
Hey John,

I am typing this here, as it just takes me too long in the webinars. My keyboard sticks, so I either type fast and then can''t see the mistakes, or I type slow and lose the subject. Plus, it might benefit someone else.


I asked about ''a lot'' of blue being good. First, I knew in my head what I meant, but it sounded wrong when asked. Of course you don''t want tons, but a decent amount, which I''ll post a stone I think has.

I understand what should be black in a round, and that some can be missing and the stone will still be pretty, just not as pretty as it would with more.

What I''m trying to understand with Princess, which I confess I know little about (that''s why I''m asking

), is just how much is just right, and when it it too much, or too little?


This one seems to have a decent amount, or, is it too much? (I doubt it)
http://www.whiteflash.com/aca_princess/A-Cut-Above-Princess-cut-diamond-174064.htm#


This one has a lot less, or, is it just right?
http://www.whiteflash.com/aca_princess/A-Cut-Above-Princess-cut-diamond-45612.htm#

I realize you may very well say both will be beautiful, and either amount is good, I just need a guideline.


I know you''re quite busy at the moment, so take your time answering, no biggie.

TIA!

I have joined picture one and picture two above into a single picture for us to look at.

Picture 1 on the left definitely has a better contrast pattern which will really make it "pop". It also has quite a bit of green, which because it is less intense than the red will also add contrast to the diamond. I did not look at the certification on this stone, but it has killer light return based on what is seen in the ASET image, and will definitely score in the top grade for light return from AGS. I definitely like the mix of light and contrast.

Picture 2 on the right is showing us incredible red light which is the more intense light striking the stone from 45 degrees up to 75 degrees. It does have less contrast but again it has a great green patch in the center which will also cause the appearance of contrast. This stone also has killer light return and will definitely score in the top grade for light return from AGS.

Genetically our eyes are hard wired to detect edges and contrasts, so we like them on an instinctual level. Were it not for contrast patterns we might as well cut little mirrors to put in our rings, then we could check out our makeup without having to pull out a compact.

For your question we can not answer for these two stones which is just right and which is too little as there is acceptable contrast in both of these stones and the patterns in both are quite symmetrical. When looking at ASET images we are looking to assess both the quantity of light return and the quality as well as the mixture of reds, greens and blues. While on a personal level I might tend to liking the pattern on the left better, my bet is that looking at these stones with the unaided eye both will be dazzling and probably very hard to tell apart.

I don''t understand your comment about what should be black in a round. In an ASET photo black is interpreted as leakage, which in a round should be minimal in a well cut stone. It is the blue contrast that we look for in both rounds and princess. You will have more black in even an well cut princess as that is the nature of the cut and the physics of light in the square shape.

I will look forward to hearing John''s take on these pictures coupled with his visual observation of the two stones. Your question is a good one, but we will need to look at more poorly cut stones to give you an example of what is too little or too much contrast.

Wink

 

[JohnQuixote]

Ellen,

Thanks for the questions.Others are working to interpret ASET images too so this may be helpful.

A couple of things in general. First, remember that rounds are different than fancy shapes because they’re more efficient at returning light.Until someone comes up with a proprietary cut that breaks some barriers (Serg?) that will always be the case.Rounds, because of their efficiency, return massive amounts of intense light return (red) - even in the ASET.

So...we have to reset our paradigms when looking at fancy shapes in ASET because we’re used to “seeing red” in fancy shape ideal-scope images.However, light return in fancy shapes is not as efficient (that’s not bad, it’s just physics).When we use the ASET what was all-red in the ideal-scope is split into red and green now, and there is far more green than we’re accustomed to seeing in rounds.Green is not bad.It’s just less intense.

With regard to obstruction:We see far less black in the IS of a fancy shape (blue in the ASET) than in a round.This is logical since the round’s spoke-like pattern of red (intense light) to black (light from different, higher angles) drives the on-off sparkle effect we see in normal viewing.Fancy shapes do not have the same signature in their sparkle, though the princess comes closest.They rely more on movement than rounds because their contrast patterns are more subtle.The balance of red and green you see should be partnered with small areas of blue (higher angle light) and areas of leakage (non-light return) which are black in the ASET when it’s not backlit.

 

[JohnQuixote]

Here are a premium round and a premium princess seen in both ideal-scope and ASET.

A premium round looks very similar in ideal-scope and ASET: Black becomes blue. White leakage becomes black (and less intense since it''s not backlit) and red is still almost all red...only the minor areas of less intense light return turn from red to green.

A premium princess looks entirely different in ideal-scope and ASET: Black still becomes blue. White leakage still becomes black, but the red is now split into many interlacing areas of red (intense light return) and green (less intense). We are not used to seeing this much green, so it takes time to learn to interpret.

Some advice; don''t overanalyze. We''re looking for as much even distribution of red as possible, then green and then pleasing contrast (caused by blue and black).

 

[JohnQuixote]

...

 

[JohnQuixote]

Date: 1/27/2007 6:15:47 PM
Author: Wink

I have joined picture one and picture two above into a single picture for us to look at.

Picture 1 on the left definitely has a better contrast pattern which will really make it 'pop'. It also has quite a bit of green, which because it is less intense than the red will also add contrast to the diamond. I did not look at the certification on this stone, but it has killer light return based on what is seen in the ASET image, and will definitely score in the top grade for light return from AGS. I definitely like the mix of light and contrast.

Picture 2 on the right is showing us incredible red light which is the more intense light striking the stone from 45 degrees up to 75 degrees. It does have less contrast but again it has a great green patch in the center which will also cause the appearance of contrast. This stone also has killer light return and will definitely score in the top grade for light return from AGS.

And there you have it. Wink has my vote for ASET ambassador to the UN.

Date: 1/27/2007 6:15:47 PM
Author: Wink

For your question we can not answer for these two stones which is just right and which is too little as there is acceptable contrast in both of these stones and the patterns in both are quite symmetrical. When looking at ASET images we are looking to assess both the quantity of light return and the quality as well as the mixture of reds, greens and blues. While on a personal level I might tend to liking the pattern on the left better, my bet is that looking at these stones with the unaided eye both will be dazzling and probably very hard to tell apart.

Exactly. Contrast patterns in princess cuts are more fluid than in rounds. I'll give a real world assessment on Monday, but I suspect Wink's prediction to be true; both dazzling and hard to tell apart performance-wise. The G will spread slightly smaller than the H of course.

 

[Ellen]

Wink, I said black, thinking about an IS image, when I should have said blue because we were talking Aset. Sorry for the confusion. And [email protected] mirror/makeup. That would be handy.

John, I think part of what I was having a hard time with was, in a round, there is a definite pattern, which is always the same. We know exactly what to look for, but the Princess is entirely different animal, so it''s a little harder to get a handle on what''s good, as there seems to be a range.

Thank you both so much for your responses, and the pics and diagrams, I really appreciate it. I think this may very well help a lot of people, it definitely helped me!

And I look forward to the assessment of these two on Monday!


p.s. John, that overanalyzing comment really wasn''t necessary, you know none of us do that.

 

[JohnQuixote]

(bump for results)

One of the things I hoped to have Brian do in the AGS0 Princess webinar today was to compare these two diamonds for you "live during the broadcast," Ellen.The technical difficulties cut us short but I just had him do this after the session.

We looked at them in his office (diffused lighting), then in sunlight and LED.The prediction that they would be hard to tell apart in overall performance was correct; they are very similarly matched.With specific regard to contrast I forced the question.We re-examined them and came to an interesting conclusion:The 1.10 (the diamond on the right, above) got the slight edge in contrast from us both.That was curious considering the slight nuances seen in the ASET images as Wink described them.We looked at their configurations and Brian says it’s not surprising considering the differences in crown height and angle combinations.Makes sense, considering (as we always must) that appealing parameters stray outside the conventions of round to round comparisons.
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[WinkHPD]

John, thank you! It is nice to see that my off site visualization was both right and wrong. Right in that they are incredibly hard to tell apart, that is as it should be since both are killer stones.

Wrong in that I would have thought the stone on the left would show slightly greater contrast. It is good to be reminded that while the ASET is an incredible tool and worth its weight in gold for determining light performance, it is still necessary to see the diamond for final decision making.

It is also worthy of noting, that if you showed those two stones to a thousand people, there would be a great number of people who would prefer one or the other, and probably an equal or greater number who would be equally happy with either stone. As was stated above, I do not think either of these stones is the better or the worser, they are both beauties worthy of having new homes.

Thanks for sharing your actual visual observations with us.

Wink

 

[Paul-Antwerp]

 

[Ellen]

John, thanks for getting back.

Interesting, not what we all expected. This really helps though, and I suspect if faced with two similar images the results could be different yet again. As Wink said, in the end, the best thing to do is have someone look at it.

Thank you for taking the time to do this, it helped me and hopefully helped others!

 

[JohnQuixote]

Ellen - It was our pleasure. We like to look at diamonds around here.

Paul - Many thanks on the photos; a high compliment coming from you.

I share your opinion about the size relationship between the magnified ASETs and actual diamonds. The right pic has larger overall areas of intense vs less intense return which could well be causing more perceivable contrast when the diamonds are reduced to their actual size in real life. While the left shows a more scattered contrast pattern human cognition is capable of perceiving only so much. At these magnifications we can enjoy the speculation but should avoid overanalysis. Brian had not seen the ASET images (obviously I had) but we came to the same conclusion IRL.

Even as I type this I am hoping I don''t do the disservice of exaggerating the differences. We had to compare several times to make a decision.