AGS introduces cut grading on DQR reports

[adamasgem]

Date: 11/1/2008 5:45:00 PM
Author: Serg


If AGS Gold came after AGS Platinum, ASG Ideal should include all AGS Platinum 0. ( there are other not very bad possibility)

Seregy: Why should they, because YOU say so. You are full of it and you know it!!!!!!!

You are trying to base an argument on the perfectly symmetric case, which doesn''t exist, and YOU purposely ignore the intent of the system to encompass the range of assymetries expected, which would effect the Platinum score.



AGS Platinum 0 charts say there is a POSSIBILITY that you get the grade, if and only if you meet other criteria

AGS GOLD charts are DETERMINISTIC in getting the grade is you meet other looser criteria..

TWO DIFFERENT THINGS.

Secondly, AGS GOLD Charts

1) were built to encomapass a WIDE RANGE of LGF''s and STARS, not just the one(s) you may have selected
2) encomapass the range of angle combinations (CA,PA) possible within the box
3) and have DIFFERENT TILT, excess weight, symmetry and polish criteria.

I don''t remember you publishing DiamondCalc score maps for all these cases, how would they overlap, and how would they be effected by assymetries.

You play the part of being ignorant of the statistics of the problem and their effect on the sensitivity in certain ranges of the map, plateaus and cliffs, and continually discard or ignore the fact that you have a terrain map with localized gradients to consider.

Give me and the rest of us some consideration for seeing through your agenda..

Karl: Send me an email through my Website, I''d like to talk to you.

 

[Serg]

Please check first 6 minutes Apple Special Event October 2008

In the end 4th minutes you can see great example like reasonable and relative good product can dramatically reduce competitiveness company.
Vista and XP are quite different products . each product has advantages and disadvantages. Maybe be for new users Vista is better . But I do not know anybody who was happy change XP to Vista , and I know a lot of persons who was very unhappy do it .

Microsoft was very successful until It tried develop most user-friendly software( better than Apple) . and most probably Vista is more user-friendly than XP.

Most user-friendly software is Apple market niche. If you should dramatically change software ( Microsoft users has not choice now, Microsoft announced the support for XP) , you will consider other vendors too .

I hope you enjoyed Apple presentation

 

[strmrdr]

Date: 11/1/2008 7:02:44 PM
Author: Serg


Please check first 6 minutes Apple Special Event October 2008



In the end 4th minutes you can see great example like reasonable and relative good product can dramatically reduce competitiveness company.

Vista and XP are quite different products . each product has advantages and disadvantages. Maybe be for new users Vista is better . But I do not know anybody who was happy change XP to Vista , and I know a lot of persons who was very unhappy do it .

Microsoft was very successful until It tried develop most user-friendly software( better than Apple) . and most probably Vista is more user-friendly than XP.

Most user-friendly software is Apple market niche. If you should dramatically change software ( Microsoft users has not choice now, Microsoft announced the support for XP) , you will consider other vendors too .


I hope you enjoyed Apple presentation

The reason vista is hurting is that it will not run well on a $400 to $500 computer and xp does and there is no compelling reason to get vista as xp does everything most people need.
Its not apple that is killing vista its cheap hardware and xp that do what people need.
The apple target market is a small percentage of the windows market that is willing to spend more money. Apple is the HOF and 8* of the computer world.
The overhead of DRM and the stiff hardware requirements it brings combined with the normal new os driver issues that still aren't resolved is what is killing vista.
Personally diamcalc is the only thing holding me back from running linux so I am staying with xp for now and will not move to vista anytime soon.

 

[michaelgem]

Date: 11/1/2008 6:11:24 PM
Author: strmrdr

Date: 11/1/2008 1:55:48 PM
Author: michaelgem

There is no other way I know of that the cutter can visually deal with such a multi-dimensional optimization problem, except to view 2-D slices of the 3-D space (table %, pav angle, crown angle) under his chosen constraints of fixed girdle %, star length, indexing, and half length.

There is a better way, use on the fly 3D calculations in the planning software taking into account cutting tolerance.
This is a perfect project for gpu acceleration and distributed computing.
A quad duel gpu sli card setup(8 gpus) could pull this off and if it cant more computers can be added using dnet clouds.
Each station would run under $7000
Computing power is cheap and this type of math and parallelization is what gpu''s were designed to do.

Yes, I agree. Some have the computing power, software and ability to explore higher dimensional optimizations even on the fly, but what good does that do the typical cutters? You still need to present the grading to the cutter in a way he can visually understand and make use of it in deciding how to optimize his cutting of rough to get the desired grade.

Notice I said: "There is no other way the cutter can visually deal with this multi-dimensional optimization problem." There is also no bettter way for the labs to communicate an understanding of their grading system and the grade ranges and boundaries to the cutter, gemologist-appraiser, or student. If there were, wouldn''t GIA, AGS or Octonus be using it?

I also note that blind reliance on any grading system no matter how good, will result in proportion sets inproperly graded unless the boundaries are explored in comparison testing of actual diamonds, as GIA did, or in comparison testing like you and I and others do with diamond simulations using software like DiamCalc.

It appears that AGS has now decided what GIA must have decided years ago, that these charts are the simplist way to communicate their grading system, and, from a practical viewpoint, adequate and sufficient to the task. A good example of Occam''s razor.

Michael

 

[Serg]

re:Occam''s razor.

http://en.wikipedia.org/wiki/Ockham_razor

"Science and the scientific method
The aforementioned problem of underdetermination poses a serious obstacle to applications of the scientific method. Formulating theories and selecting the most promising ones is impossible without a way of choosing among an arbitrarily large number of theories, all of which fit with the evidence equally well. If any one principle could single-handedly reduce all these infinite possibilities to find the one best theory, at first glance one might deduce that the whole of scientific method simply follows from it, and thus that it alone would be sufficient to power the whole process of hypothesis formulation and rejection scientists undertake."

 

[Garry H (Cut Nut)]

Date: 11/1/2008 8:01:10 PM
Author: strmrdr

Date: 11/1/2008 7:02:44 PM
Author: Serg



Please check first 6 minutes Apple Special Event October 2008




In the end 4th minutes you can see great example like reasonable and relative good product can dramatically reduce competitiveness company.

Vista and XP are quite different products . each product has advantages and disadvantages. Maybe be for new users Vista is better . But I do not know anybody who was happy change XP to Vista , and I know a lot of persons who was very unhappy do it .

Microsoft was very successful until It tried develop most user-friendly software( better than Apple) . and most probably Vista is more user-friendly than XP.

Most user-friendly software is Apple market niche. If you should dramatically change software ( Microsoft users has not choice now, Microsoft announced the support for XP) , you will consider other vendors too .


I hope you enjoyed Apple presentation

The reason vista is hurting is that it will not run well on a $400 to $500 computer and xp does and there is no compelling reason to get vista as xp does everything most people need.
Its not apple that is killing vista its cheap hardware and xp that do what people need.
The apple target market is a small percentage of the windows market that is willing to spend more money. Apple is the HOF and 8* of the computer world.
The overhead of DRM and the stiff hardware requirements it brings combined with the normal new os driver issues that still aren''t resolved is what is killing vista.
Personally diamcalc is the only thing holding me back from running linux so I am staying with xp for now and will not move to vista anytime soon.

Aside from computers Karl, did you get the point?

 

[michaelgem]

Date: 11/2/2008 5:31:25 AM
Author: Serg
re:Occam''s razor.

http://en.wikipedia.org/wiki/Ockham_razor

''Science and the scientific method
The aforementioned problem of underdetermination poses a serious obstacle to applications of the scientific method. Formulating theories and selecting the most promising ones is impossible without a way of choosing among an arbitrarily large number of theories, all of which fit with the evidence equally well. If any one principle could single-handedly reduce all these infinite possibilities to find the one best theory, at first glance one might deduce that the whole of scientific method simply follows from it, and thus that it alone would be sufficient to power the whole process of hypothesis formulation and rejection scientists undertake.''

My use of the term Occam''s razor is a commonly used one which means:

The best theory or solution to a problem is the simplist solution that adequately explains the observations, or as wikipedia says it:

"All other things being equal, the simplest solution is the best."

In the case of cut grading: There is no clearer, better or simpler way for the labs to communicate an understanding of their grading system and the grade ranges and boundaries to the cutter, gemologist-appraiser, or student.

Michael

 

[michaelgem]

Date: 11/2/2008 10:05:24 AM
Author: michaelgem

Date: 11/2/2008 5:31:25 AM
Author: Serg
re:Occam''s razor.

http://en.wikipedia.org/wiki/Ockham_razor

''Science and the scientific method
The aforementioned problem of underdetermination poses a serious obstacle to applications of the scientific method. Formulating theories and selecting the most promising ones is impossible without a way of choosing among an arbitrarily large number of theories, all of which fit with the evidence equally well. If any one principle could single-handedly reduce all these infinite possibilities to find the one best theory, at first glance one might deduce that the whole of scientific method simply follows from it, and thus that it alone would be sufficient to power the whole process of hypothesis formulation and rejection scientists undertake.''

My use of the term Occam''s razor is a commonly used one which means:

The best theory or solution to a problem is the simplist solution that adequately explains the observations, or as wikipedia says it:

''All other things being equal, the simplest solution is the best.''

In the case of cut grading: There is no clearer, better or simpler way for the labs to communicate an understanding of their grading system and the grade ranges and boundaries to the cutter, gemologist-appraiser, or student.

Michael

At the risk of offending sensibilities, which always gets me in trouble, I''d like to address again the insistence of some that presenting a 3-D light-performance-based grading system using charts is in any way "two dimensional" or "proportion based". This is just plain nonsense intended to denigrate labs that use this chart method of communicating their grading systems.

Using charts, as Sergey has, to communicate the properties of the 3-D, light-performance-based, AGS PGS grading system in a way that the cutter can visually deal with, by reducing a multi-dimensional optimization problem to 2-D slices of the 3-D space of table %, pav angle, and crown angle, in no way makes it proportion based or two dimensional.

Continuing use of these terms is evidence of misunderstanding or an agenda.

Michael

 

[michaelgem]

Date: 11/2/2008 6:16:46 AM
Author: Garry H (Cut Nut)

Date: 11/1/2008 8:01:10 PM
Author: strmrdr

Date: 11/1/2008 7:02:44 PM
Author: Serg
Please check first 6 minutes Apple Special Event October 2008


In the end 4th minutes you can see a great example of how a reasonable and relative good product can dramatically reduce a company''s competitiveness.

Vista and XP are quite different products . Each product has advantages and disadvantages. Maybe be for new users Vista is better . But I do not know anybody who was happy to change from XP to Vista , and I know a lot of persons who were very unhappy to do it .

Microsoft was very successful until it tried to develop the most user-friendly software( better than Apple) . and most probably Vista is more user-friendly than XP.
Most user-friendly software is Apple market niche. If you are forced to dramatically change software, you will consider other vendors too .


I hope you enjoyed Apple presentation

Aside from computers Karl, did you get the point?

One of the many things to appreciate about Sergey, is his ability to communicate his big picture understanding and world view of how the labs and other entities in the diamond industry are affecting the industries bottom line, profitability and competitivness with other products.

His contributions, which never loose sight of the big picture, help keep our detailed discussions in proper perspective.

Michael

 

[strmrdr]

Date: 11/2/2008 11:04:54 AM
Author: michaelgem

At the risk of offending sensibilities, which always gets me in trouble, I'd like to address again the insistence of some that presenting a 3-D light-performance-based grading system using charts is in any way 'two dimensional' or 'proportion based'. This is just plain nonsense intended to denigrate labs that use this chart method of communicating their grading systems.

When charts are used for the actual grading using averages it is a 2D proportion based system!

If you recall the thread on creating charts AGS and I were in agreement that charts can not accurately reflect a 3D grading system and that was the reason they were not releasing charts beyond the cutting guidelines.

The new grading system is clearly 2D and proportion based just like the GIA system.

Present it however you want but what counts is how the actual grading is done.

2D systems are broad based rejection systems and are not accurate enough for selection.
3D systems are the gateway to a selection system and the min. standard acceptable.
Actual Scope Image based systems are the best selection systems when combined with a c/p angle filter.
AGS has downgraded the AGS Ideal grade from a just over the border of acceptable selection system to a rejection system with the gold grades.

 

[michaelgem]

Date: 11/2/2008 3:01:51 PM
Author: strmrdr

Date: 11/2/2008 11:04:54 AM
Author: michaelgem

At the risk of offending sensibilities, which always gets me in trouble, I''d like to address again the insistence of some that presenting a 3-D light-performance-based grading system using charts is in any way ''two dimensional'' or ''proportion based''. This is just plain nonsense intended to denigrate labs that use this chart method of communicating their grading systems.

When charts are used for the actual grading using averages it is a 2D proportion based system!

If you recall the thread on creating charts AGS and I were in agreement that charts can not accurately reflect a 3D grading system and that was the reason they were not releasing charts beyond the cutting guidelines.

The new grading system is clearly 2D and proportion based just like the GIA system.

Present it however you want but what counts is how the actual grading is done.

2D systems are broad based rejection systems and are not accurate enough for selection.
3D systems are the gateway to a selection system and the min. standard acceptable.
Actual Scope Image based systems are the best selection systems when combined with a c/p angle filter.
AGS has downgraded the AGS Ideal grade from a just over the border of acceptable selection system to a rejection system with the gold grades.

All I can do is explain, as I already have, the reality that a 3-D performance based system does not in any sense suddenly become 2-D or proportion based just because charts and tables are created in order to communicate to the cutter or us the combinations of table size, pav and crown angles that will receive, when combined with all the other constraints, an Ideal or Ex grade. The charts for each table size are a visual presentation of this 3-D relationship and interaction between table, pavilion and crown with every other variable held constant at nominal values.

The terms selection vs. rejection for grading systems is semantic nonsense. Charts allow the cutter to select the combinations that yield the top grades, and by so doing they are simultaneously rejecting combinations that do not.

If AGS is responsible for the kind of thinking you have expressed here, then perhaps it is karma that you and others are now having such a problem with their Gold system.

The main problem I have with their two systems is the problem Sergey has been pointing out. When the Gold Ideal and Platinum Ideal are displayed on the same apples to apples basis, such as Sergey has done with his chart generation, the results should be the same. Otherwise, you have two definitions for the all-important-to-AGS Ideal grade. This is a branding nightmare that Sergey and I believe AGS should rectify for their own benefit, if not their own viability.

They, even if not you, certainly need to loose the incorrect and pejoritive terminology of 2-D and proportion based for 3-D performance based systems communicated through the use of charts and tables.

Michael

 

[Regular Guy]

Date: 11/2/2008 4:56:12 PM
Author: michaelgem

The terms selection vs. rejection for grading systems is semantic nonsense. Charts allow the cutter to select the combinations that yield the top grades, and by so doing they are simultaneously rejecting combinations that do not.

Michael,

The ideas, and points of view being represented here, are pretty thick, and I''d rather not stick my neck in where it doesn''t belong. But, I find it troubling where simple ideas, at least to me, are not understood, or even recognized. In this discussion, so often, I do not know if there is the communication problem is one of just not being willing to step out from around the counter and see the same situation from the other person''s point of view...rather than that there is any actual disagreement about anything.

In the case of the text captured above...I can tell you what the words are intended to mean. Also...it seems to me the words are very substantive to what may be important to many of us, concerning the bad feeling about gold, as it''s understood and being represented. Whether or not it is true that a crown & pavilion coordinate system being met gives a high five makes it easier or not for a cutter...I want to know under what circumstance, as a shopper, I can buy, or recommend another to buy...based on the information provided. With HCA, Garry has vehemently made it clear...that with the information provided...one can only reject if not included...one should not recommend based on the information at hand alone.

In contrast...based on my understanding of what the contemporary "Platinum" 0 has represented, with the efficiency of words Karl has used...we might feel actually more able to, without the otherwise usually required qualification...make a "buy" suggestion, based on the information at hand alone. It is a question of what information is sufficient to be satisfied that the diamond has been described sufficiently well, that one can have "confidence" that it will perform. And so now, despite my own vocal antagonism toward AGS for their description of what has been the "0" for light performance, and my complaints against them for representing what they should not be doing, calling this "light performance," since I have been accusing them of extrapolating from the data too much in making the statement...so now...I am finding myself defending this very conceptual position...against the alternative, I suppose.

Anyway...on either the chance you actually did not understand Karl''s point...which, to all purposes...seems to actually have been the case, or simply just to put to words which you failed to do...to say that it is semantics to suggest that selection or rejection are associated with these two systems is either to not understand a core idea for many of us, to to regard this as irrelevant...and I hope this post might contribute to correcting what seems to be a misunderstanding, in either case.

 

[adamasgem]

Date: 11/2/2008 4:56:12 PM
Author: michaelgem
The main problem I have with their two systems is the problem Sergey has been pointing out. When the Gold Ideal and Platinum Ideal are displayed on the same apples to apples basis, such as Sergey has done with his chart generation, the results should be the same.

The main point you and Sergey conveniently miss, is that they are two different systems, and should not be compared they way you are trying to do on an apples to apples basis, because it is like comparing apples and oranges.

SERGEY IS NOT COMPARING APPLES TO APPLES.

I think we all had this same conceptual problem when we compared AGSPGS and GIA.

The differences in the criteria used can only suggest that there appears to be more selectivity in one system over another, just the same way you could justifiibly say that about AGSPGS and AGS GOLD.

 

[strmrdr]

Date: 11/2/2008 4:56:12 PM
Author: michaelgem

The terms selection vs. rejection for grading systems is semantic nonsense.

No it is not it is the core of the issue.
2D systems do not have a high enough confidence level to used by consumers for selection.
3D systems if well done can have a high enough confidence level to used for selection.
The AGS DQD/PGS system just barley is enough if nothing else is available to use for selection.
I would much rather an IS image to go with it but if forced to go without then I would consider it.

You can not accurately model a diamond from averaged several times then rounded data and have enough accurate information to make a selection.

 

[adamasgem]

Date: 11/2/2008 6:38:30 PM
Author: adamasgem

Date: 11/2/2008 4:56:12 PM
Author: michaelgem
The main problem I have with their two systems is the problem Sergey has been pointing out. When the Gold Ideal and Platinum Ideal are displayed on the same apples to apples basis, such as Sergey has done with his chart generation, the results should be the same.

The main point you and Sergey conveniently miss, is that they are two different systems, and should not be compared they way you are trying to do on an apples to apples basis, because it is like comparing apples and oranges.

SERGEY IS NOT COMPARING APPLES TO APPLES.

I think we all had this same conceptual problem when we compared AGSPGS and GIA.

Typo line should have read.

The differences in the criteria used can only suggest that there appears to be more selectivity in one system over another, just the same way you could justifiibly say that about AGSPGS and GIA.

 

[michaelgem]

Date: 11/2/2008 5:48:27 PM
Author: Regular Guy

Date: 11/2/2008 4:56:12 PM
Author: michaelgem

The terms selection vs. rejection for grading systems is semantic nonsense. Charts allow the cutter to select the combinations that yield the top grades, and by so doing they are simultaneously rejecting combinations that do not.

Michael,

I find it troubling where simple ideas, at least to me, are not understood, or even recognized. In this discussion, so often, I do not know if there is the communication problem is one of just not being willing to step out from around the counter and see the same situation from the other person's point of view...rather than that there is any actual disagreement about anything.

I want to know under what circumstance, as a shopper, I can buy, or recommend another to buy...based on the information provided. It is a question of what information is sufficient to be satisfied that the diamond has been described sufficiently well, that one can have 'confidence' that it will perform.

Anyway...on either the chance you actually did not understand Karl's point...which, to all purposes...seems to actually have been the case, or simply just to put to words which you failed to do...to say that it is semantics to suggest that selection or rejection are associated with these two systems is either to not understand a core idea for many of us, to to regard this as irrelevant...and I hope this post might contribute to correcting what seems to be a misunderstanding, in either case.

Ira and Karl,

Thanks so much to you both for explaining what you and others mean by labling a system as acceptance or rejection type. I took these terms literally, as anyone not familiar with the useage you have explained would be liable to do. This usage, as a core idea is certainly far from irrelevant.

I hope this misunderstanding of intended meaning does not divert from the main ideas I was addressing.

You see that just like the pejoritive and flat wrong application of the terms 2-D and proportion based to the GIA and AGS-gold systems, the implication that either chart-and-table communicated system is only a broad based rejection system and not accurate enough for selection is equally pejorative and equally wrong.

After all, cutters are using charts and tables to cut to proportions indicated to be Ideal or Ex, and they are consistantly getting Ideal calls from AGSL and Ex calls from GIA when they submit those diamonds.

If AGS goes back, and at least for nominal values of the other variables, generates charts for the range of Gold Ideal and PGS Ideal 0 that are in agreement, we could all breath a sigh of relief, even if they retained less stringent polish requirements for the Gold Ideal. Non-performance related, craftsmanship issues like Ideal polish are of a lot less concern than the implications of chart disagreements. They should not have avoided for so long the generation of 3-D performanced-based, cutter guidline charts using nominal values for minor facets from their PGS software, as Sergey's team has done. They could have served as the basis for the Gold Ideal.

I recognize and acknowledge the difficulties, especially if the performance criteria for Gold Ideal has been altered from that of the Ideal 0, such as a change in tilt requirements. I believe any changes in performance criteria for Ideal should be applied equally to both to maintain a single standard for their "bread and butter" brand, the AGS Ideal.

Under these circumstances of future agreement between Gold and Platinum standards, the answer to your question would go as follows:

The extent that you believe that PGS software operating on the Sarin scan of your diamond is a "selection" system, is also the extent that you can believe in the Gold Ideal standard as a "selection" system.

This is largely because both AGS and GIA impose high symmetry requirements on Ideal and Ex, so the light performance varies insignificantly enough from the measured parameters vs their averages giving you the same results for the same diamond proportions.

With some more work and effort on the part of AGSL and their very capable researchers, we logically should reach the same level of comfort (whether that level was "selection" or only "rejection") with the new Gold Ideal that we had with the Platinum Ideal.

Michael

 

[Regular Guy]

Michael,

To help get us back on the same page, you might reflect on this page in the Pricescope tutorial, and weigh in with respect to your thoughts on the 3 systems described.

I''ve kind of taken a sports enthusiast model for my own involvement here...rather than that of a player. But, I read from those who are users...i.e., do more extensive, personal, clinical trials, with respect to their own shopping and comparisons...is that when Karl says:

Date: 11/2/2008 3:01:51 PM
Author: strmrdr


2D systems are broad based rejection systems and are not accurate enough for selection.
3D systems are the gateway to a selection system and the min. standard acceptable.
Actual Scope Image based systems are the best selection systems when combined with a c/p angle filter.
AGS has downgraded the AGS Ideal grade from a just over the border of acceptable selection system to a rejection system with the gold grades.

...I understand from Karl, and other regulars...that using reflector technologies..both IS and ASET, to double check what is seen visually...frequently diamonds that might be thought to otherwise perform well based on an ostensibly good crown & pavilion combination...prove out maybe not to be so under that test.

So, forgetting imputing an ideal idea from Tolkowski or Morse, and any other proportion foundations...the thought, as I''ve seen it discussed here...is that the actual performance is pretty reliably vetted with reflector technologies...and to determine which diamonds you wish to asses with these technologies...you might first be guided to these by an examination of crown & pavilion angles, to then perform such further clinical tests. Obviously, the use of reflector technologies are thought to enhance, much like a loop, what the good old eye can do....but provide a neutral context of a lighting environment for comparison.

This is some of the background I come here with. I really should do more clinical work myself...but I understand that actual observed non-performance in purported ideals, proved with reflector technologies, and such...are much of what is driving the desire for a more perfected analysis of performance.

 

[adamasgem]

Date: 11/2/2008 8:38:56 PM
Author: michaelgem


This is largely because both AGS and GIA impose high symmetry requirements on Ideal and Ex, so the light performance varies insignificantly enough from the measured parameters vs their averages giving you the same results for the same diamond proportions.

1) Those symmetry requirements have never been presented as to the statistics of angle sets, versus the symmetry "classification" given by either lab, unfortunately

2) You CANNOT MAKE THE STATEMENT YOU DO (highliighted),as a generality It depends on where you are on the map. Please get that through your head. You have ABSOLUTELY NO DATA to back it up.

 

[adamasgem]

Date: 11/2/2008 8:38:56 PM
Author: michaelgem

I recognize and acknowledge the difficulties, especially if the performance criteria for Gold Ideal has been altered from that of the Ideal 0, such as a change in tilt requirements. I believe any changes in performance criteria for Ideal should be applied equally to both to maintain a single standard for their ''bread and butter'' brand, the AGS Ideal.

Michael, I''m sure you would like the highlighted statement to be done, but it would require a minimum of 17 times the computer time to do that, as has been clearly pointed out to you before.

What you "believe" is to ask for (or demand) a currently impossible task, to make AGS look bad, because with current computing power, no one using PGS software would wait for the time required to do the task you ask, and you know it.

I would simply suggest that AGS the GOLD IDEAL report grade be renamed the GOLD PREMIUM report grade, as has been previously suggested, and then all the rhetoric you and others have been spouting about so called illusionary confusion will be moot.

 

[Serg]

AGS Gold, ASG Platinum and GIA cut grading systems are DIFFIRENT CUTTING Grading systems( What have same proposition To grade diamonds)

Because its are different and because its are cutting grading systems, comparison is Necessary and Important .( for consumers , cutters, retailers, Labs)

ASG Gold and GIA cut grading system have same data presentation. Both of them use set of parameters to grade diamond

AGS Platinum uses 3D model of diamond to grade diamond.

I do not any person who said what comparison between ASG Platinum and GIA cut grading system
1) Is impossible
2) OR Is necessary
3) OR False task,
4) OR Confusing consumers
5) OR Dodging subject

But when I did attempt do SAME TASK for ASG Platinum and ASG GOLD, I received all these and much more accusations.

Please show me ANY technical difference between two tasks:

1) Comparison between ASG Platinum and GIA cut grading system
2) Comparison between ASG Platinum and AGS Gold

BTW Classical and relativistic mechanics are different too. Should we compare these twp mechanics ? Should we check what relativistic mechanics will give same results in classical mechanical filed responsibility ?
Suppose what Any persons say . NO, they are so different, we should not even try do comparison . Will you continue discussion with him?

 

[michaelgem]

Date: 11/3/2008 2:51:24 AM
Author: Serg

AGS Gold, ASG Platinum and GIA cut grading systems are DIFFERENT CUT Grading systems( That have the same proposition: To grade diamonds)

Because they are different and because they are cut grading systems, comparison is Necessary and Important ( for consumers , cutters, retailers, Labs)

ASG Gold and GIA cut grading system have same data presentation. Both of them use set of parameters to grade diamond.

AGS Platinum uses 3D model of diamond to grade diamond.

I do not know of any person who said that a comparison between ASG Platinum and GIA cut grading system

1) Is impossible
2) OR Is necessary
3) OR False task,
4) OR Confusing consumers
5) OR Dodging subject

But when I did attempt to do the SAME TASK for ASG Platinum and ASG GOLD, I received all these and much more accusations.

Please show me ANY technical difference between these two tasks:

1) Comparison between ASG Platinum and GIA cut grading system
2) Comparison between ASG Platinum and AGS Gold



BTW Classical and relativistic mechanics are different too. Should we compare these twp mechanics ? Should we check what relativistic mechanics will give the same results in classical mechanical field ?
Suppose that Any persons says: NO, they are so different, we should not even try to do a comparison . Would you continue discussion with him?

Sergey has framed the issues here so perfectly that I cannot improve upon it. I will simply add the following IMO necessary and key additional points:

Re: ASG Gold and GIA cut grading system have same data presentation. Both of them use set of parameters to grade diamond.

The fact that a set of parameters, intelligently averaged and quantized, are input to either the Gold or GIA system using tables and graphs does not make it, by any stretch, proportion based or 2-D.

The AGS Gold system is based upon computer models of diamond proportion sets that are 3-D ray traced and evaluated by their performance based cut grading metrics, which is the same basis as their Platinum system.
Re: AGS Platinum uses 3D model of diamond to grade diamond.

And the AGS Gold uses 3D model of diamonds to grade each proportion combination making up each entry in their Charts. This is the same 3-D light performance basis for both Platinum and Gold systems.

Michael

 

[strmrdr]

Date: 11/3/2008 1:21:14 PM
Author: michaelgem



Re: ASG Gold and GIA cut grading system have same data presentation. Both of them use set of parameters to grade diamond.


The fact that a set of parameters, intelligently averaged and quantized, are input to either the Gold or GIA system using tables and graphs does not make it, by any stretch, proportion based or 2-D.




Re: AGS Platinum uses 3D model of diamond to grade diamond.


And the AGS Gold uses 3D model of diamonds to grade each proportion combination making up each entry in their Charts. This is the same 3-D light performance basis for both Platinum and Gold systems.


Michael

If they were based on the same criteria they would agree with each other and Serg wouldn''t be getting grey hair from trying to integrate it into his cutting recommendations.
They can not return 2 different answers and have the same criteria.

Any system that uses 1 averaged and rounded number to represent 8 or more facets is 2D and proportion based regardless of the science behind it.
GIA and AGS Gold are 2D.
It can not approach the accuracy of a 3D system where every facet is taken into account.
When you get to the edges of a grade the difference is huge.
When it comes to preventing and in some cases correctly rewarding tricks the difference is huge, there can be no question that 3D has a huge advantage.
When it comes to the level of confidence one should place in a system the differences are huge.

Calling the results from 2 very different systems AGS Ideal is a very bad thing and undermines the work AGS has done.
It will create confusion in the market place and open the door to false marketing.

AGS Gold benefits AGS and the trade there is no upside for consumers therefor it should be rejected.
With the economy the way it is and the low level of respect the average person on the street has of the industry doing this is just another sign that the industry can''t be trusted and works against the work AGS and the good vendors have done.
It is a slap on the face to those that have supported AGS and tough standards.

 

[michaelgem]

Karl and any like minded individuals,

It is clear that the only agreement we will ever reach is to "agree to disagree", so this is my last attempt to clarify, not for you, but for others, the areas of complete disagreement.

You say any grading system communicated to cutters and us with tables and charts is 2D and proportion based. That terminology refers to systems like the original AGS grading system. This system graded deviations from the Tolkowsky Ideal, which Marcel derived from a 2D, mains-and-table-only outline of the round brilliant. As a consequence, the sweet spot range of Ideal had rectangular boundaries, because the system did not account for the 3D light interaction between all the facets.

All three systems in question here, GIA, AGS Gold and Plat are based upon the 3D light interaction between all 57 facets. The chart's used by GIA and AGS reveal Ex and Ideal boundaries that are non-rectangular, and show the interrelationship between crown and pavilion mains and table. These charts represent a 3D range sliced up and presented with 2D charts for each table size.

The term "2D proportion based" that applied to the old Tolkowsky based system simply does not apply to these three, 3D light-performance-based cut grading systems.

The nature of how the information is presented in the new AGS Gold system and GIA's system requires that thresholds for grades be set within the charts quantization constraints. Chart representations of both grading systems are simply methods to visually communicate to cutters and us the boundaries of each grade.

AGS has chosen to simplify their light performance based system (no longer having distinctions for 4, 6, 8, 10 mm etc) and set boundaries that work with this 3D/2D chart form of presentation. Their motivation was not to dumb down their respected light performance based metrics, but rather to relieve confusion and complaints by many cutters. That the exact boundaries are different is no surprise. The boundaries for each size were different, and now they have one universal size.

It is a simplification, and a simplification of a system respected for its detail in raytracing the diamond model from the complete Sarin scan. To anyone who loves the Platinum system, the new one looks dumbed-down. In reality, it is a simplification of the same 3D light-performance-based system with necessary smoothing of boundaries for simplicity of presentation and use by cutters and others.

Michael

 

[beryl]

Garry:

I just dropped in to see what''s up (yardening season is over).
The chart you presented 10/16 (and Serg enlarged, thankfully) looks a bit familiar.
It appears that we have come full circle - back to simplicity.

 

[Garry H (Cut Nut)]

Date: 11/4/2008 2:26:47 AM
Author: beryl
Garry:

I just dropped in to see what''s up (yardening season is over).
The chart you presented 10/16 (and Serg enlarged, thankfully) looks a bit familiar.
It appears that we have come full circle - back to simplicity.

The good old 5:1 ratio that you discusssed at the IDCC conference in Moscow Bruce - and note the new system extends down deeper into shallow crowns.

There is a considerable debate going on about the idea of using charts for cut grading, and if the two AGSL systems should overlap. Unfortunately it has not always been as polite.

 

[strmrdr]

Date: 11/3/2008 7:50:18 PM
Author: michaelgem
Karl and any like minded individuals,


It is clear that the only agreement we will ever reach is to 'agree to disagree', so this is my last attempt to clarify, not for you, but for others, the areas of complete disagreement.


You say any grading system communicated to cutters and us with tables and charts is 2D and proportion based. That terminology refers to systems like the original AGS grading system. This system graded deviations from the Tolkowsky Ideal, which Marcel derived from a 2D, mains-and-table-only outline of the round brilliant. As a consequence, the sweet spot range of Ideal had rectangular boundaries, because the system did not account for the 3D light interaction between all the facets.


All three systems in question here, GIA, AGS Gold and Plat are based upon the 3D light interaction between all 57 facets. The chart's used by GIA and AGS reveal Ex and Ideal boundaries that are non-rectangular, and show the interrelationship between crown and pavilion mains and table. These charts represent a 3D range sliced up and presented with 2D charts for each table size.


The term '2D proportion based' that applied to the old Tolkowsky based system simply does not apply to these three, 3D light-performance-based cut grading systems.


The nature of how the information is presented in the new AGS Gold system and GIA's system requires that thresholds for grades be set within the charts quantization constraints. Chart representations of both grading systems are simply methods to visually communicate to cutters and us the boundaries of each grade.


AGS has chosen to simplify their light performance based system (no longer having distinctions for 4, 6, 8, 10 mm etc) and set boundaries that work with this 3D/2D chart form of presentation. Their motivation was not to dumb down their respected light performance based metrics, but rather to relieve confusion and complaints by many cutters. That the exact boundaries are different is no surprise. The boundaries for each size were different, and now they have one universal size.


It is a simplification, and a simplification of a system respected for its detail in raytracing the diamond model from the complete Sarin scan. To anyone who loves the Platinum system, the new one looks dumbed-down. In reality, it is a simplification of the same 3D light-performance-based system with necessary smoothing of boundaries for simplicity of presentation and use by cutters and others.


Michael

For the 10th time how it is presented to cutters doesn't make it 2D or 3D how the grade is assigned does!

You call it smoothing borders I call it pandering to the trade and creating a less trustworthy system and creating confusion for consumers by having 2 vastly different criteria called AGS Ideal.

yep we can agree to disagree....but I will continue to fight for consumers on this issue.

 

[Serg]

Date: 11/4/2008 2:26:47 AM
Author: beryl
Garry:

I just dropped in to see what''s up (yardening season is over).
The chart you presented 10/16 (and Serg enlarged, thankfully) looks a bit familiar.
It appears that we have come full circle - back to simplicity.

Hi Beryl,

Please enjoy new comparison chart. We added PGS results for odd strings ( thanks Janak)

Dark Black line is boundary PGS 0

Parameters used in PGS: 3% girdle bezel, 55% Star (45% upper girdle) and 80% lower girdle facet length (81.5% lower facet depth).

If chart is too big, please inform me. I will ask delete it and publish smaller chart

Re: It appears that we have come full circle - back to simplicity.

Definitely . Too simple for current time. 3-5 years ago it would be good solution. But now It seems like capitulation

Now anybody can create similar charts . DC images with structure lights are enough to create a lot of similar “cut grading systems”. Specially if you use H&A structure light
AGS Gold has not more the very important part of ASG identity .( 3D light performance grade )
It definitely step back. For my opinion it is very bad for ASG identity, this step wash out ASG identity

 

[adamasgem]

Date: 11/4/2008 6:06:36 AM
Author: Garry H (Cut Nut)
There is a considerable debate going on about the idea of using charts for cut grading, and if the two AGSL systems should overlap. Unfortunately it has not always been as polite.

Unfortunately Garry, you have NEVER sat in on a real engineering discussion, where important issues, that may eventually mean life and death, are discussed. I have, and they were between a lot of people with advanced degrees, undoubtedly much smarter than most of those who participate here.

A classic public example may have been the very heated discussions where ignorant management types with misplaced agendas, overruled engineers at Morton Thiokol, which led to the Challenger disaster, or shall I say disgrace.

If you can''t take the heat, get out of the frying pan, or keep your mouth shut.
It is not about politeness, it is about facts and logic vs misinformation being fed to the public.

 

[adamasgem]

Date: 11/4/2008 2:26:47 AM
Author: beryl
Garry:

I just dropped in to see what''s up (yardening season is over).
The chart you presented 10/16 (and Serg enlarged, thankfully) looks a bit familiar.
It appears that we have come full circle - back to simplicity.

Bruce, drop me an email please..

 

[adamasgem]

Date: 11/4/2008 9:06:57 AM
Author: Serg

Dark Black line is boundary PGS 0

What is misleading in your comparison is that you continually fail to mention that the Dark Black line is a boundary where there is a only a POSSIBILITY of getting a 0, in the real world, but not a GUARANTEE, because it is based entirely on PERFECT symmetry, which doesn''t exist, and you don''t know the gradients or probabilities of getting that ellusive 0.

In fact at the boundarys of the grade, you ought to look at the sensitivity of scanning errors (variances) by running PGS with multiple scans, and not only presenting the quantized results.. remember 0.49 is a 0 and 0.51 is a 1.0

You are not telling the complete picture Sergey.

If you analyse the stone completely, you may or may not get a better grade

And besides the criteria are different, and it would take 17 times as long to make all the runs to do the equivilant processing on the actual stone (PGS) , and no one in the TRADE wants to pay for that extra time.

"Cheaper, Faster, Better" is a Mantra of the TRADE (and maybe some of the buying public), as it was for ill fated NASA management. The trade seems to want decisions from the labs (or tools) that could mean 10''s of thousands of dollars (typically thosands) made in little or no time, which results in work with less confidence in the work product.

Real stupid on the trades part, in my opinion.