isee2 versus HCA on AGS0 an graded diamond

[diamund]

I recently purchased an AGS0 H&A diamond... I ran it thru an isee2 machine, and it scored excellent on symmetry, but terrible on scintilation and brilliance. Oh, and this same stone scores a 0.7 on the HCA!!!!

There were two girls who I''m not sure if they knew what they were doing set up the isee2 machine.. I just watched. Is it possible to screw itup - either intentionally or unintentionally?


What gives????????????????????

 

[Rhino]

You have discovered one of the weakness'' of the HCA diamund. A great scoring diamond on the HCA can suffer in diffuse light conditions (which is the type of analysis being done on the Isee2). The HCA, the IdealScope (along with the other red reflectors), & also the BrillianceScope (in most circumstances) do not account for light performance in these kind of light conditions. Most of the tools you see being used on the net to differentiate between the various cuts do not do what the Isee2 does. The Isee2 is the only technology that measures brilliance (contrast brilliance at that), scintillation & symmetry in diffuse light conditions.

I am however conducting a study on the correllation of Isee2 results along with BrillianceScope Light View 6 as I am finding a direct correllation between Isee2 results and the images produced in BS view 6 (which is taken in diffuse light).

In any case here is one such example...

This diamond has the following proportions which produces an HCA score of 1.0 based on the angles.

 

[Rhino]

Here is that diamonds LightScope results. I don''t think any poster on this forum would say NO to this image.

 

[Rhino]

And finally here are the HCA results. Many people purchasing on the net only take their research as far as an IS image and HCA results. There''s more to this however than just an IS image and HCA results.

 

[diamund]

Thanks much for the answers!

Ok.. the fact that HCA assumes direct light conditions is news to me. That makes more sense... Hmmm... Since most lighting situations in real life are diffuse, would it make more sense then to place more weight on the isee2 rather than HCA in real life?


Best Regards

 

[Rhino]

Isee2 results accurately reveal a super symmetry grade (which it does) however that set of proportions, while looking very nice in direct light conditions ... you bring the stone into more suffuse conditions and you get too much head obstruction (too many darks as opposed to lights). The contrast is offset and brilliance is reduced.

As this is a fairlly new study for me I am only beginning to become familar with what sets of proportions produce this effect and they must all be correllated with human eye observation. The stones I have studied thus far, I was able to see the differences with my eyes.

 

[Rhino]

Date: 1/26/2005 3

9:36 PM
Author: diamund
Thanks much for the answers!

Ok.. the fact that HCA assumes direct light conditions is news to me. That makes more sense... Hmmm... Since most lighting situations in real life are diffuse, would it make more sense then to place more weight on the isee2 rather than HCA in real life?


Best Regards

Yes is my answer to that question. Diamonds are observed most often in softer light conditions than they are stronger light conditions.

Also ... there is a possibility that the ladies screwed up too but that is unlikely as the technology is pretty much idiot proof.

 

[strmrdr]

Rhino if you still have that stone inhouse can you take and post some indirect light photos side by side with an isee2 9.8 rated stone?

 

[Garry H (Cut Nut)]

http://www.diamond-cut.com.au/07_gilbertson.htm

 

[Garry H (Cut Nut)]

How firey is it?

 

[Rank Amateur]

To my eye, the girdle profile looks a little funky. Is the table tilted?

 

[WinkHPD]

Rhino,

I have a hard time taking Icee2 too sieriously when they only let the people who sell their diamonds have access to it. Call me old fashioned, but when someone tells me they have the latest greatest technology, but then only will they let you even see it if you agree to buy x amount of diamonds from them it makes me "curious" about the validity of the equipment.

I like the various H&A type scopes and the firescope, but most of all I like the eye. If my eye tells me the stone is a screamer, I really don´t care too much what any one´s equipement tells me. I can appreciate that they are all trying to tell the masses what diamond is the most beautiful and make it easier for people to choose a stone sight unseen, but I will always believe that a good return period and people looking at stones with their eyes to see if they like what the machines like or something different is going to be the way to go.

Wink

 

[Garry H (Cut Nut)]

No - no table tilt - the crown and pavilion angles would have more variance if the table had a titl - remeber it doubles the variance.

It has an assymmetry which makes you wonder about the symmetry measure though.

The stone hasd lower girdle facets that are too short for that small sized table.
That is one reason why the stone returns less light.
the other is more questionable - it is the old arguement that i am right and everyone else is wrong.
When the fat lady sings da da de de

 

[diamund]

Rhino,

I know you say you''re just beginning with your research into this HCA vs diffuse light conditions... But have you formulated a range of dimensions that score high HCA but score low ISEE2... ? To me that would be the next step - to establish sometype of correction factor for the HCA to modify the score as if in diffuse light conditions.

 

[strmrdr]

Date: 1/26/2005 8:58:48 PM
Author: diamund
Rhino,


I know you say you''re just beginning with your research into this HCA vs diffuse light conditions... But have you formulated a range of dimensions that score high HCA but score low ISEE2... ? To me that would be the next step - to establish sometype of correction factor for the HCA to modify the score as if in diffuse light conditions.

Its not that easy.
Not that im an expert but there is more to indirect light performance than the few measurements the hca takes into account.

 

[ICAA]

Wink: I took my diamond to a jeweller who has an Isee2 machine. ITs not an Isee2 diamond. Its a 1.004 carat RBC, Canadian, Sarin report proven ideal cut, GIA excellent/excellent, VS2, F colour. Based on the Sarin and GIA report, I anticipated excellent brilliance, excellent scintillation and above average symmetry. Sure enough, it scored as I expected. It scored a 9.2. I have seen diamonds that were not Isee2 diamonds on the machine that scored superb - 9.0+, including mine. I do not believe the Isee2 machine "favours" Isee2" cut stones based on their reputation and my practical experience with the machine. Isee2, as a lab cuts excellent stones and I believe the machine is a way to help market their product through an independent, objective measure. The GIA, Sarin, and AGS report cannot tell you about the performance of the diamond. The Isee2 machine is another way to prove their diamonds are quality stones.

For reference, it scores a 1.3 on the Holloway Cut Adviser. Excellent Light Return, Fire and Scintillation. Very good spread.

As an aside, the nice thing about the machine is that it allows you to focus on, what I consider the most important elements, brilliance and scintillation. I would rather have a 9.2 stone that, for all intents, tops out the brilliance and scintillation scores and lower on the symmetry than vice versa.

 

[JohnQuixote]

Date: 1/26/2005 6:38:20 PM
Author: Wink

I like the various H&A type scopes and the firescope, but most of all I like the eye. If my eye tells me the stone is a screamer, I really dont care too much what any ones equipement tells me. I can appreciate that they are all trying to tell the masses what diamond is the most beautiful and make it easier for people to choose a stone sight unseen, but I will always believe that a good return period and people looking at stones with their eyes to see if they like what the machines like or something different is going to be the way to go.

Wink

I have to agree with Wink's statement here. Nothing beats a trusted, live advocate on the job.

When it comes to beauty, "dynamic performance" devices like B’Scope and Isee2 attempt to judge something too vast and subjective to quantify in terms of numbers. It’s not that I don’t appreciate the technology: I believe those machines capable of separating high and low performers within their specific ranges of operation.

However, machines cannot possibly make judgments of taste. One diamond scoring slightly higher or lower than another cannot be termed as less or more beautiful, because humans see beauty differently. Generations of diamond cutters have worked to discover and refine many types of diamond beauty to suit humanity’s broad palate. A sudden mechanical interpretation of beauty is not acceptable as a replacement for the many variations in taste among all people.

…And don’t even get me started on the attempt to judge scintillation.

For purposes of internet shopping, Sarin-type numbers which are now commonly provided, along with predictors like the HCA, a light-leakage image, a H&A image (if you’re seeking H&A) and a magnified photo are a great way to select final candidates.

Once you’ve separated the shiny wheat from the chaff it should always come down to human observation: Ideally a trusted vendor’s and/or appraiser’s and finally your own.

 

[ICAA]

John - I agree with your statement that beauty is in the eye-of-the-beholder/machines cannot judge taste. For myself, I believed that based on the specs and myself looking at the diamond I purchased, it was an awesome diamond. For myself, the Isee2 machine was a way to reinforce that my choice was a good one. The results on the machine did not surprise me, so I was happy.

 

[JohnQuixote]

Date: 1/26/2005 11:45:52 PM
Author: ICAA
John - I agree with your statement that beauty is in the eye-of-the-beholder/machines cannot judge taste. For myself, I believed that based on the specs and myself looking at the diamond I purchased, it was an awesome diamond. For myself, the Isee2 machine was a way to reinforce that my choice was a good one. The results on the machine did not surprise me, so I was happy.

No problem there.

I also take interest in playing with them - just to see what they will "see."

The uh-oh pings my radar when people try to use those numbers to split hairs between high-performing diamonds over the 'net rather than relying on a trusted pair (or pairs) of eyes.

 

[Garry H (Cut Nut)]

A number of times when this has come up in the past I have asked for an explanation as to why the good and bad CZ''s we sell on ideal-scope.com - both scored +9.

Sergey say ISee2 last year at basel.

He had several complaints.

 

[Serg]

.

 

[diamund]

false alert!!

I took my stone to another jeweler who had an isee2. This guy knew how to run / calibrate the thing, and my stone put up impressive numbers.

Goes to show the variance. You think something is idiot proof, but a better idiot is invented!

Peace All

 

[Serg]

Date: 1/28/2005 2:25:43 PM
Author: diamund
false alert!!

I took my stone to another jeweler who had an isee2. This guy knew how to run / calibrate the thing, and my stone put up impressive numbers.

Goes to show the variance. You think something is idiot proof, but a better idiot is invented!

Peace All

Crazy.

 

[Rhino]

Date: 1/26/2005 3:33:27 PM
Author: strmrdr
Rhino if you still have that stone inhouse can you take and post some indirect light photos side by side with an isee2 9.8 rated stone?

That stone was sent back to the supplier strm. However I have been collecting some graphics that demonstrate this point and was going to post a more indepth article on the blog forum including more of the other technical aspects . Here are some shots of 2 stones in diffuse light conditions. Both are low scoring HCA diamonds. The pix in diffuse conditions reveal the differences I''m talking about rather obviously.

Peace,

 

[Rhino]

Hi Wink!

Hope you had a great trip and good to see you back. My response will be between yours.

Date: 1/26/2005 6:38:20 PM
Author: Wink
Rhino,

I have a hard time taking Icee2 too sieriously when they only let the people who sell their diamonds have access to it. Call me old fashioned, but when someone tells me they have the latest greatest technology, but then only will they let you even see it if you agree to buy x amount of diamonds from them it makes me ''curious'' about the validity of the equipment.

Do you think I just blindly walked into a decision for that without thoroughly testing it out? Wink... believe me ... when a company makes a little black box and says "look at MY diamonds in it" and ONLY their diamonds look good in it and make others look bad that are cut equally as nice or nicer do you think I would fall for such a thing? I hope you think better of me friend. Truth be told ... when we went to test the technology my top rated stones scored even higher than the manufacturer who was showing the technology. I like to think I''ve become pretty adept to testing out the claims of new technologies considering my familiarity and years of working with them. I''ll tell you something funny though... the inventors couldn''t quite pin down the type and nature of the Isee2 analysis. A few months of study with it and I''ve got a strong handle on exactly what it''s showing. Most importantly I can demonstrate the correlations between its results and human eye observation. If it did not correllate with human eye observation I''d be the first to debunk it and DEMONSTRATE WHY.

It''s kinda funny hearing you say this though Wink cause there is always ONE brand that appears better under one particular black box that you seem to be fond of.

I like the various H&A type scopes and the firescope, but most of all I like the eye. If my eye tells me the stone is a screamer, I really don´t care too much what any one´s equipement tells me. I can appreciate that they are all trying to tell the masses what diamond is the most beautiful and make it easier for people to choose a stone sight unseen, but I will always believe that a good return period and people looking at stones with their eyes to see if they like what the machines like or something different is going to be the way to go.

Wink

Please don''t take my positive comments of the Isee2 technology to detract from human eye observation. I never discout that and always seek to find the correlations between modern technologies and human observation. If technology says one thing and human eye observation says something completely different, I''m all for what the lady likes. That is not the case here. I''d like to also clarify something too which can really confuse clients (including the readers of this board) when it comes to "human eye observation".

You will see many people saying "trust your eyes". "As long as it looks good buy it!"

The problem with this kind of advice (and I''m not necessarily talking about you Wink) is that most consumers ... when left to the judgement of their *eyes*, are for the most part going out to a jewelry store and comparing crap next to another one that is not as crappy and picking the stone that isn''t as crappy without ever having compared to a true top of the line rock which in many circumstances they can purchase for a comparable price. You see what I''m gettin at? Also... say John Q. Public walks into a store and the sales clerk looks em in the eye and says ... "I am an expert and this is one of the most beautiful diamonds you can get for the money!" I shop my competition here locally and hear this gobledeegook all the time. Sadlly there are folks who buy it hook, line and sinker and never ask for any proof. Call me stubborn but I like to see *reasons why* that extend outside the salesclerks word and a pair of amateur eyes.

I don''t mind saying it either but there are many salesclerks in jewelry stores who think they know everything about diamonds and I can point you to a plethora of people who participate on these boards ... CONSUMERS AT THAT... who know more than many diamond salespeople in jewelry stores.

Peace,

 

[Rhino]

Date: 1/26/2005 8:58:48 PM
Author: diamund
Rhino,

I know you say you''re just beginning with your research into this HCA vs diffuse light conditions... But have you formulated a range of dimensions that score high HCA but score low ISEE2... ? To me that would be the next step - to establish sometype of correction factor for the HCA to modify the score as if in diffuse light conditions.

Strmrdr''s response was correct. There''s more to it and I don''t have all the time that Gary has on his hands to formullate an HCA for diffuse light conditions. (just joshin ya there mate).

Just as it is with direct light conditions so is it with diffuse light conditions. There will be sets of angles that flatter a diamonds appearance in those conditions and those that won''t. I examine each on a stone for stone basis. I am familair with many combinations that produce this ill effect but there are many combinations I''ve yet to test. Each diamond is a new adventure.

 

[Rhino]

Date: 1/26/2005 10:29:29 PM
Author: ICAA
Wink: I took my diamond to a jeweller who has an Isee2 machine. ITs not an Isee2 diamond. Its a 1.004 carat RBC, Canadian, Sarin report proven ideal cut, GIA excellent/excellent, VS2, F colour. Based on the Sarin and GIA report, I anticipated excellent brilliance, excellent scintillation and above average symmetry. Sure enough, it scored as I expected. It scored a 9.2. I have seen diamonds that were not Isee2 diamonds on the machine that scored superb - 9.0+, including mine. I do not believe the Isee2 machine ''favours'' Isee2'' cut stones based on their reputation and my practical experience with the machine. Isee2, as a lab cuts excellent stones and I believe the machine is a way to help market their product through an independent, objective measure. The GIA, Sarin, and AGS report cannot tell you about the performance of the diamond. The Isee2 machine is another way to prove their diamonds are quality stones.

For reference, it scores a 1.3 on the Holloway Cut Adviser. Excellent Light Return, Fire and Scintillation. Very good spread.

As an aside, the nice thing about the machine is that it allows you to focus on, what I consider the most important elements, brilliance and scintillation. I would rather have a 9.2 stone that, for all intents, tops out the brilliance and scintillation scores and lower on the symmetry than vice versa.

Thanks for sharing that ICAA. I also agree with your final assessment too. One aspect about the symmetry grading that I do like about the Isee2 is that it rewards superior craftsmanship and is examing the precision of optical symmetry in a diamond. Cutting a diamond with precise optical symmetry takes up to 4x as long to cut and I appreciate the fact that the Isee2 rewards a cutter for taking his time to do it right. Currently it is the only technology that analyzes this metric.

 

[Rhino]

Date: 1/27/2005 9:55:46 AM
Author: Serg
.

Thanks for the confirmation Serg. You know I have the .srn file with the 3d model posted of that particular stone too if you''d like to see it. Your model looked a little too perfect however the results are virtually identical between the model you constructed (based on the OGI) and the .srn file that I had imported into DiamCalc.

Peace,

 

[Garry H (Cut Nut)]

Date: 1/27/2005 4:18:26 AM
Author: Garry H (Cut Nut)
A number of times when this has come up in the past I have asked for an explanation as to why the good and bad CZ''s we sell on ideal-scope.com - both scored +9.

any comments Rhino?

 

[Dancing Fire]

Rhino you said....

You will see many people saying "trust your eyes". "As long as it looks good buy it!"


The problem with this kind of advice (and I'm not necessarily talking about you Wink) is that most consumers ... when left to the judgement of their *eyes*, are for the most part going out to a jewelry store and comparing crap next to another one that is not as crappy and picking the stone that isn't as crappy without ever having compared to a true top of the line rock which in many circumstances they can purchase for a comparable price. You see what I'm gettin at? Also... say John Q. Public walks into a store and the sales clerk looks em in the eye and says ... "I am an expert and this is one of the most beautiful diamonds you can get for the money!" I shop my competition here locally and hear this gobledeegook all the time. Sadlly there are folks who buy it hook, line and sinker and never ask for any proof. Call me stubborn but I like to see *reasons why* that extend outside the salesclerks word and a pair of amateur eyes.

Rhino

i agree 110% of what you're saying. i rather trust a honest vendor and a independent appraiser's eyes rather than my own pair however,i still would want to see the stone myself after getting their opinion ,they probably handle more diamonds in one month than i will ever see in my whole life.even those $1999 per ct special at Zales might look like a GODZILLA stone to the avg consumer because, they haven't seen or compare it to a top cut stone.....so i'll say "don't buy it" unless you see enough really nice cut stones and have some idea.