Quantifying Performance Nuances beyond ASET, H&A Photos, etc

[JoshuaNiamehr]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

+1 for this thread.

There are some physical measurement devices out there that are able to quantify light symmetry and other metrics, do you think they are part of the future of quantification of performance nuances?

Hi Josh,

It depends on what technology you're talking about. I have worked intimately with just about every technology out there from ASET, Bscope, Isee2, Sarine, sophisticated versions of IdealScope, Octonus Raytrace, OGI ray trace, etc. as well as correlating those results with real world observation. All of them have their strengths and all of them also have their limitations. We take the approach of "test all things, hold fast to that which is good". Technologies are great for communicating strengths and weakness of certain products but it is important that consumers know the limitations of them as well.

Regards,
Rhino

Hi Rhino,

Lets use the Sarine Light as an example - it is calibrated to measure optical performance and light symmetry. I believe its the only device that actually measures light symmetry physically.

Joshua

Hi Josh,

I had Sarine Light here and tested numerous diamonds on it whose results I have saved. It is what was formerly the Isee2 technology which I had used for roughly a decade but wanted to test the new algorithms. As an advocate of online technologies and one who was eager to re-employ the technology ... after seeing the results I had to pass. To rely upon it as any form of "grading system" no less ... not a good idea.

Regards,
Rhino

Hi Rhino,

I would think that consumers would benefit from quantification vis-à-vis calibrated measures of optical symmetry over H&A claims that can easily be exaggerated by members of this trade.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

In the exercise you have constructed you are able to see patterns and relative sparkle sizes and distribution. It is like a vastly blown up version of what your eye sees. And it brings the concept of virtual facets out of the realm of theoretical ray tracing and into the real world visual realm. Very cool

Hi Bryan,

Thank you for the compliment..., it took a lot of hard work getting to this point of being able to control our cutting process in such a way.
You are right, this is exactly what it does, it is plainly what your eyes see, I plan on adding some more images explaining this phenomena better. It does change our capability to better understand the meaning of real life "Light Performance" when it comes to Diamonds and high precision cutting works. While we are in the midst of R&D the light return/performance aspect of Real ETAS this exercise is aimed more to show the ability it has to measure the Diamond's cut symmetry in the most accurate fashion.

If anyone wishes to apply the test towards two H&A AGS 0 graded cuts it would be interesting to see the results, I am willing to bet we would be able to pick one who has better cut symmetry. I would do such a test but don't have access to RB's as we don't cut those.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

Hi teobdl,

Regarding your first question, my answer is I honestly don't know.

Now to your second...

ASET shows and translates where (direction) the Diamond is drawing its light from (as in the world is lit from above as per AGSL grading model), Red (primary), green (secondary), blue (obstruction) and black/white (leakage).

Real ETAS shows us useful information about the real facets and virtual facets of the Diamond in the most sensitive and detailed manner which can accurately indicate about optical symmetry and the optical potential of the Diamond.

 

[teobdl]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

Hi teobdl,

Regarding your first question, my answer is I honestly don't know.

Now to your second...

ASET shows and translates where (direction) the Diamond is drawing its light from (as in the world is lit from above as per AGSL grading model), Red (primary), green (secondary), blue (obstruction) and black/white (leakage).

Real ETAS shows us useful information about the real facets and virtual facets of the Diamond in the most sensitive and detailed manner which can accurately indicate about optical symmetry and the optical potential of the Diamond.

But doesn't ETAS also show where the diamond reflection sources are? In ETAS, assuming all light is coming from the pin point, ETAS is essentially a reverse ray trace to find where all sources are in real life. In fact, it's much more helpful than ASET because an ETAS measure is continuous rather than having whole ranges blocked into colors (like in ASET).

Another huge benefit of ETAS is one can literally see where and to what extent white light is broken into spectral colors.

Other than seeing some of the real facets of a diamond in ASET, I'm struggling to see the utility of ASET when ETAS is so easy.

 

[hiratop]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Everybody seems stuck at this point but Quantifying Performance Nuances beyond ASET, H&A Photos is definitely doable on REAL ETAS.
Its an easy test anyone can have fun doing, take any polished Diamond you want tested (branded or generic) and place it table top on a glass (would probably work with a mounted rings).
Then take a dark colored cardboard and puncture a small hole (allowing the light path of either a flashlight or laser through it) and attach flashlight (similar to white led as in your phone) to the hole allowing the light to pass through.
Keep an approx. 1.20 inches (30mm) distance between cardboard and glass (by laying both between books or similar). Now light the flashlight/laser and aim the light to the center of the Diamond laying face down on the glass (the more centered the better the results.)
Results will reflect actual the “3D light symmetry” of the Diamond being tested.
The higher the symmetry level of the light paths displaying/reflecting on the cardboard the higher the symmetry level of the cut itself.
Easy…
Attached is a drawing displaying the simple setup (forgive my handwriting.)
Attached is also an image of a Real ETAS (photographed at 30mm distance) displaying 3D light symmetry results of a recent Octavia Diamond we cut.



Real ASET Octavia

What effect does the glas have on the result? Would it be better to replace it with another cardboard with a round hole filled with the diamond?

 

[Rockdiamond]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

Hi teobdl,

Regarding your first question, my answer is I honestly don't know.

Now to your second...

ASET shows and translates where (direction) the Diamond is drawing its light from (as in the world is lit from above as per AGSL grading model), Red (primary), green (secondary), blue (obstruction) and black/white (leakage).

Real ETAS shows us useful information about the real facets and virtual facets of the Diamond in the most sensitive and detailed manner which can accurately indicate about optical symmetry and the optical potential of the Diamond.

But doesn't ETAS also show where the diamond reflection sources are? In ETAS, assuming all light is coming from the pin point, ETAS is essentially a reverse ray trace to find where all sources are in real life. In fact, it's much more helpful than ASET because an ETAS measure is continuous rather than having whole ranges blocked into colors (like in ASET).

Another huge benefit of ETAS is one can literally see where and to what extent white light is broken into spectral colors.

Other than seeing some of the real facets of a diamond in ASET, I'm struggling to see the utility of ASET when ETAS is so easy.

Is your world "lit from above"?
Mine is lit from many different angles- which constantly change in the diamond as it moves

 

[KobiD]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Is your world "lit from above"?
Mine is lit from many different angles- which constantly change in the diamond as it moves

I understand what you are saying David, but for the purpose of testing, validating, and quantifying the data one has to limit the variables so regardless of method IS/ASET/ETAS limiting the direction the light enters the diamond is a simply way to achieve that.

From the little I have seen regarding Real ETAS though, I imagine it would be quite easy to implement testing through various angles and get a better idea of what is happening in the output, where an IS/ASET simply shows up as leakage.

 

[Rockdiamond]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Is your world "lit from above"?
Mine is lit from many different angles- which constantly change in the diamond as it moves

I understand what you are saying David, but for the purpose of testing, validating, and quantifying the data one has to limit the variables so regardless of method IS/ASET/ETAS limiting the direction the light enters the diamond is a simply way to achieve that.

From the little I have seen regarding Real ETAS though, I imagine it would be quite easy to implement testing through various angles and get a better idea of what is happening in the output, where an IS/ASET simply shows up as leakage.

I also get your point- which reminds me of an old Buddhist ( I think) tale.

One night, a man sees another man searching the ground under a street light.
"What are you looking for?"
"I dropped my keys."

He stops to help.
After a few moments he asks the fellow
"Are you sure you dropped them here?"

"No, I dropped them over there but I'm searching under the light because I can see better here."

Standardizing a lighting environment that does not reflect actual lighting is giving us results that are skewed.

 

[KobiD]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

FWW, I quickly rigged something up as suggested by Yoram. I snapped a couple photos on the shoddy old camera but they didn't turn out very good. I'll try again later this evening in the dark, with the digital SLR if time permits.

One thing that was immediately evident, was that if you didn't align the light, hole, and diamond correctly you had buckleys chance of getting a symetrical display. As things came together, it did indeed highlight any differences in symmetry between the facets which could be seen as either sets closer/further apart. Our little diamond is an AGS0 which lacks precision to an extent where you can pick it up in the arrows, let alone what the hearts looks like.

It would be great to have another precision cut to compare back to back.

Also, rotating and moving the diamond above the light source shows how the diamond responds to varying angles of light. Precision of the patterning changes of course, however it still clearly demonstrates a quanity of light being returned.

 

[Serg]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

Real ETAS can be used as a Diamond signature/fingerprint because each Diamond cut has its specific arrangement depicting hundreds (or thousands when taking tilts into account) of those reflective light dots as Sergey's example of Gemprint's usage.

For example, a perfect RB like the default model offered in DiamCalc would exhibit a perfect symmetrical map of those reflective light dots on Real ETAS just as it does in DC ETAS. As soon as you start changing its facet structure it will lose its symmetrical figure. This allows us to measure which Real ETAS map is closer to "perfection".

While I agree with Sergey we can't get a cut grade based on such results yet, you can definitely get accurate info regarding the optical symmetry of a Diamond cut.

 

[Serg]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

Real ETAS can be used as a Diamond signature/fingerprint because each Diamond cut has its specific arrangement depicting hundreds (or thousands when taking tilts into account) of those reflective light dots as Sergey's example of Gemprint's usage.

For example, a perfect RB like the default model offered in DiamCalc would exhibit a perfect symmetrical map of those reflective light dots on Real ETAS just as it does in DC ETAS. As soon as you start changing its facet structure it will lose its symmetrical figure. This allows us to measure which Real ETAS map is closer to "perfection".

While I agree with Sergey we can't get a cut grade based on such results yet, you can definitely get accurate info regarding the optical symmetry of a Diamond cut.

Yoram,
there are at least 2 problems to use ETAS for optical symmetry grade
1) Human asymmetry grade is not linear ( it is not just number spots, pixels which are not symmetric) . One big asymmetrical zone is more critical than 2 small zones with same total area .
two adjacent VF's can have very big distance between correspondence ETAS spots.
so grade by VF's and by ETAS spots will different for Human
2) some 3D asymmetry gives small changes in VF's symmetry( for example in H&A pictures) but huge difference in ETAS symmetry, other 3D asymmetry gives big changes in VF's symmetry but small changes in ETAS picture.
for example compare azimuth variation for pavilion main facet RBC, and LGF ratio variation .
3) ETAS spot size=VF size+(angular light spot size)*distance. for most VF's real size is much less than (angular light spot size)*distance.
so two VF's with quite different real size will looks similar on ETAS picture.
So small VF facet with big angular asymmetry destroy ETAS while this facet is almost invisible for Human

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

Real ETAS can be used as a Diamond signature/fingerprint because each Diamond cut has its specific arrangement depicting hundreds (or thousands when taking tilts into account) of those reflective light dots as Sergey's example of Gemprint's usage.

For example, a perfect RB like the default model offered in DiamCalc would exhibit a perfect symmetrical map of those reflective light dots on Real ETAS just as it does in DC ETAS. As soon as you start changing its facet structure it will lose its symmetrical figure. This allows us to measure which Real ETAS map is closer to "perfection".

While I agree with Sergey we can't get a cut grade based on such results yet, you can definitely get accurate info regarding the optical symmetry of a Diamond cut.

Yoram,
there are at least 2 problems to use ETAS for optical symmetry grade
1) Human asymmetry grade is not linear ( it is not just number spots, pixels which are not symmetric) . One big asymmetrical zone is more critical than 2 small zones with same total area .
two adjacent VF's can have very big distance between correspondence ETAS spots.
so grade by VF's and by ETAS spots will different for Human
2) some 3D asymmetry gives small changes in VF's symmetry( for example in H&A pictures) but huge difference in ETAS symmetry, other 3D asymmetry gives big changes in VF's symmetry but small changes in ETAS picture.
for example compare azimuth variation for pavilion main facet RBC, and LGF ratio variation .
3) ETAS spot size=VF size+(angular light spot size)*distance. for most VF's real size is much less than (angular light spot size)*distance.
so two VF's with quite different real size will looks similar on ETAS picture.
So small VF facet with big angular asymmetry destroy ETAS while this facet is almost invisible for Human

Sergey,

I understand and value your take on human perception and physics.
I am merely a Diamond designer and cutter. I would rather focus our R&D on the Diamond optical potential as I believe there is plenty more to discover in that arena. I will definitely follow your studies and findings on human perception and will conclude on it in the future when it's clearer.

Now with focus on Real ETAS.

Large or small VF's are less but still clearly noticeable on Real ETAS.
After all, large/small VF's are actually reflections of large/small actual facets.
When we cut to the precision level we are talking about or as some vendors choose to outline as "super" Ideals, some either large or small facets require fine tuning of the angles and azimuths of adjacent and/or further located large or small facets in order to achieve the high optical symmetry level we aim to. This type of fine tuning is clearly noticeable on Real ETAS.

Sergey, if you take 2 similar RB's with AGS 0/H&A which both have a similar ASET and test them to their Real ETAS you will be able to tell the difference. You will be able to point out to the one with the better objectively measured optical symmetry.

 

[Serg]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

Real ETAS can be used as a Diamond signature/fingerprint because each Diamond cut has its specific arrangement depicting hundreds (or thousands when taking tilts into account) of those reflective light dots as Sergey's example of Gemprint's usage.

For example, a perfect RB like the default model offered in DiamCalc would exhibit a perfect symmetrical map of those reflective light dots on Real ETAS just as it does in DC ETAS. As soon as you start changing its facet structure it will lose its symmetrical figure. This allows us to measure which Real ETAS map is closer to "perfection".

While I agree with Sergey we can't get a cut grade based on such results yet, you can definitely get accurate info regarding the optical symmetry of a Diamond cut.

Yoram,
there are at least 2 problems to use ETAS for optical symmetry grade
1) Human asymmetry grade is not linear ( it is not just number spots, pixels which are not symmetric) . One big asymmetrical zone is more critical than 2 small zones with same total area .
two adjacent VF's can have very big distance between correspondence ETAS spots.
so grade by VF's and by ETAS spots will different for Human
2) some 3D asymmetry gives small changes in VF's symmetry( for example in H&A pictures) but huge difference in ETAS symmetry, other 3D asymmetry gives big changes in VF's symmetry but small changes in ETAS picture.
for example compare azimuth variation for pavilion main facet RBC, and LGF ratio variation .
3) ETAS spot size=VF size+(angular light spot size)*distance. for most VF's real size is much less than (angular light spot size)*distance.
so two VF's with quite different real size will looks similar on ETAS picture.
So small VF facet with big angular asymmetry destroy ETAS while this facet is almost invisible for Human

Sergey,

I understand and value your take on human perception and physics.
I am merely a Diamond designer and cutter. I would rather focus our R&D on the Diamond optical potential as I believe there is plenty more to discover in that arena. I will definitely follow your studies and findings on human perception and will conclude on it in the future when it's clearer.

Now with focus on Real ETAS.

Large or small VF's are less but still clearly noticeable on Real ETAS.
After all, large/small VF's are actually reflections of large/small actual facets.
When we cut to the precision level we are talking about or as some vendors choose to outline as "super" Ideals, some either large or small facets require fine tuning of the angles and azimuths of adjacent and/or further located large or small facets in order to achieve the high optical symmetry level we aim to. This type of fine tuning is clearly noticeable on Real ETAS.

Sergey, if you take 2 similar RB's with AGS 0/H&A which both have a similar ASET and test them to their Real ETAS you will be able to tell the difference. You will be able to point out to the one with the better objectively measured optical symmetry.

Yoram,
What is Your main Goal: Amazing Craftsmanship or Highest Light Performance ?

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

1a) Russian cutters used similar tool ( with laser as light source, and hemisphere with marked angles ) it early(around 40 years ago) as express quality control in semipolish stage and for final polished round diamonds.
1b) Gemprint uses it for identification and promotes it for LP.
1c) several years ago Lexus assembled similar tool( with full spectrum light source) for few cutters.

ETAS is Helpful for understanding some weaknesses in cut design , but such tool is not good for cut grade( neither for LP nor for symmetry) ( many reasons and it is long story). I use it as rejection tool only.
2) Head obscuration Distribution in visual cut pattern

Real ETAS can be used as a Diamond signature/fingerprint because each Diamond cut has its specific arrangement depicting hundreds (or thousands when taking tilts into account) of those reflective light dots as Sergey's example of Gemprint's usage.

For example, a perfect RB like the default model offered in DiamCalc would exhibit a perfect symmetrical map of those reflective light dots on Real ETAS just as it does in DC ETAS. As soon as you start changing its facet structure it will lose its symmetrical figure. This allows us to measure which Real ETAS map is closer to "perfection".

While I agree with Sergey we can't get a cut grade based on such results yet, you can definitely get accurate info regarding the optical symmetry of a Diamond cut.

Yoram,
there are at least 2 problems to use ETAS for optical symmetry grade
1) Human asymmetry grade is not linear ( it is not just number spots, pixels which are not symmetric) . One big asymmetrical zone is more critical than 2 small zones with same total area .
two adjacent VF's can have very big distance between correspondence ETAS spots.
so grade by VF's and by ETAS spots will different for Human
2) some 3D asymmetry gives small changes in VF's symmetry( for example in H&A pictures) but huge difference in ETAS symmetry, other 3D asymmetry gives big changes in VF's symmetry but small changes in ETAS picture.
for example compare azimuth variation for pavilion main facet RBC, and LGF ratio variation .
3) ETAS spot size=VF size+(angular light spot size)*distance. for most VF's real size is much less than (angular light spot size)*distance.
so two VF's with quite different real size will looks similar on ETAS picture.
So small VF facet with big angular asymmetry destroy ETAS while this facet is almost invisible for Human

Sergey,

I understand and value your take on human perception and physics.
I am merely a Diamond designer and cutter. I would rather focus our R&D on the Diamond optical potential as I believe there is plenty more to discover in that arena. I will definitely follow your studies and findings on human perception and will conclude on it in the future when it's clearer.

Now with focus on Real ETAS.

Large or small VF's are less but still clearly noticeable on Real ETAS.
After all, large/small VF's are actually reflections of large/small actual facets.
When we cut to the precision level we are talking about or as some vendors choose to outline as "super" Ideals, some either large or small facets require fine tuning of the angles and azimuths of adjacent and/or further located large or small facets in order to achieve the high optical symmetry level we aim to. This type of fine tuning is clearly noticeable on Real ETAS.

Sergey, if you take 2 similar RB's with AGS 0/H&A which both have a similar ASET and test them to their Real ETAS you will be able to tell the difference. You will be able to point out to the one with the better objectively measured optical symmetry.

Yoram,
What is Your main Goal: Amazing Craftsmanship or Highest Light Performance ?

Not amazing but superb craftsmanship combined with Ideal Light Designed Diamonds when chosen.
Also I am talking about fancy shaped Diamonds as my main goal.
Another one of my main goals is to help develop tools which will allow me and other cutters to achieve such results.


This image reflects this fairly well...

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

FWW, I quickly rigged something up as suggested by Yoram. I snapped a couple photos on the shoddy old camera but they didn't turn out very good. I'll try again later this evening in the dark, with the digital SLR if time permits.

One thing that was immediately evident, was that if you didn't align the light, hole, and diamond correctly you had buckleys chance of getting a symetrical display. As things came together, it did indeed highlight any differences in symmetry between the facets which could be seen as either sets closer/further apart. Our little diamond is an AGS0 which lacks precision to an extent where you can pick it up in the arrows, let alone what the hearts looks like.

It would be great to have another precision cut to compare back to back.

Also, rotating and moving the diamond above the light source shows how the diamond responds to varying angles of light. Precision of the patterning changes of course, however it still clearly demonstrates a quanity of light being returned.

I am happy to hear someone is trying this test, it should be fun for any cut aficionado.
Imagine you have an enlarged area showing this symmetrical display of light while you use a measuring device to measure these closer/further spaces.

Please give it another attempt, it will be nice to see someone do such a test at home.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Yoram,
Thank you for that. This is a very simple setup and seems easily reproducible. Two questions:
1) why isn't it used more widely as an evaluation tool?
2) what are some major things about a diamond's light "performance" that you can't learn from ETAS but which you might learn with ASET?

Hi teobdl,

Regarding your first question, my answer is I honestly don't know.

Now to your second...

ASET shows and translates where (direction) the Diamond is drawing its light from (as in the world is lit from above as per AGSL grading model), Red (primary), green (secondary), blue (obstruction) and black/white (leakage).

Real ETAS shows us useful information about the real facets and virtual facets of the Diamond in the most sensitive and detailed manner which can accurately indicate about optical symmetry and the optical potential of the Diamond.

But doesn't ETAS also show where the diamond reflection sources are? In ETAS, assuming all light is coming from the pin point, ETAS is essentially a reverse ray trace to find where all sources are in real life. In fact, it's much more helpful than ASET because an ETAS measure is continuous rather than having whole ranges blocked into colors (like in ASET).

Another huge benefit of ETAS is one can literally see where and to what extent white light is broken into spectral colors.

Other than seeing some of the real facets of a diamond in ASET, I'm struggling to see the utility of ASET when ETAS is so easy.

Is your world "lit from above"?
Mine is lit from many different angles- which constantly change in the diamond as it moves

Hi David, I didn't think you would want to participate on such a technical debate but since you did comment let me give you a short answer....

AGSL's world is lit from above only when it comes to grading Diamonds LP.
That is one of the main reasons we are further trying to find ways to test the optical potential of a cut Diamond.

My world is definitely not lit from above (you should know this well!), Real ETAS doesn't just allow testing light coming from above but has the potential of testing multiple lights coming from multiple angles and directions and we believe much more....
Actually this is why we are confident a tool like Real ETAS can help us move forward into the future of light designed Diamonds.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

BTW, we just conducted this exercise but in stead of aiming the reflective lights towards a board we aimed the light to the face of an observer. Interestingly whenever we noticed a specific color (from the spectrum) on the eye of the observer he called viewing the same colored flash, in this case Blue.

 

[Texas Leaguer]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

BTW, we just conducted this exercise but in stead of aiming the reflective lights towards a board we aimed the light to the face of an observer. Interestingly whenever we noticed a specific color (from the spectrum) on the eye of the observer he called viewing the same colored flash, in this case Blue.

Yoram, that is fascinating!

Standing by to see more...

 

[Karl_K]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

BTW, we just conducted this exercise but in stead of aiming the reflective lights towards a board we aimed the light to the face of an observer. Interestingly whenever we noticed a specific color (from the spectrum) on the eye of the observer he called viewing the same colored flash, in this case Blue.

Now that is kewl!

 

[Serg]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

BTW, we just conducted this exercise but in stead of aiming the reflective lights towards a board we aimed the light to the face of an observer. Interestingly whenever we noticed a specific color (from the spectrum) on the eye of the observer he called viewing the same colored flash, in this case Blue.

Yoram,
thanks for great photos.
How many meters are between diamond and eye?

 

[teobdl]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

This is why ETAS is such a powerful tool-- you can literally see the distribution, character, and frequency of light. Many small white dots = highly probable white scintillation*. A few big rainbowed stripes = broad colored flashes.

*I say "highly probable" because many pinpoint flashes from different parts of a diamond can "sum" to a single spot and appear brighter than the individual reflection points actually are.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

BTW, we just conducted this exercise but in stead of aiming the reflective lights towards a board we aimed the light to the face of an observer. Interestingly whenever we noticed a specific color (from the spectrum) on the eye of the observer he called viewing the same colored flash, in this case Blue.

Yoram,
thanks for great photos.
How many meters are between diamond and eye?

Hi Sergey,

Not really meters. we tested on a much closer distance and with a LED light.
We will test natural & direct sunlight and I will post some more images..., hopefully soon...

 

[Rockdiamond]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Amazing stuff Yoram!!

The "lit from above" supposition being used to determine LP is failing of the system IMO.
Hopefully change is coming in this regard.

 

[diagem]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

Amazing stuff Yoram!!

The "lit from above" supposition being used to determine LP is failing of the system IMO.
Hopefully change is coming in this regard.

The lit from above is an AGSL LP grading limitation. They recognize its limitation.
It's not failing it's just going to be improved via natural evolution.
You bet change is coming but don't view it as a potential failure. LP R&D is not going away anytime soon. We are barely scratching its potential especially for fancy shapes.

 

[Rockdiamond]

Re: Quantifying Performance Nuances beyond ASET, H&A Photos,

I agree- it was a poor choice of words Yoram.

The AGSL system is groundbreaking, and works well in the way it was intended.
Broadening he goals and definitions will definitely improve the system.

 

[Medical]

Quantifying Performance Nuances beyond ASET, H&A Photos, etc

Thanks for the kind words, Bryan! This thread has been extremely educational- and I'm continually amazed by how much the trade is willing to share on this forum, I can't think of another field this open to discussion. Truly remarkable.

Yoram- that is very cool! I think it would be extremely interesting to see some ETAS with the light coming from different angles someday! It definitely allows you to measure things easier.

Serg/Garry- It seems like when it comes to quantifying the light in diamonds, you have two kinds of systems that can be used- one that objectively measures light return without the eye-brain interface, and one that measures perceived light return post human processing. One of the things that's been on my mind is that when it comes to ASET, it doesn't tell you much about intensity of light return, correct? Just the angles from which the light is returned? Is there a threshold of intensity of light being returned to see red as opposed to say, leakage?