Is BrillianceScope Reliable?

[Rhino]

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On 1/18/2004 12:22:25 AM Rank Amateur wrote:





How does GemEx 'certify' a score without having the stone sent to them? Why not just send them the stone?
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One reason I think Rank is becuase in the images you can see a number of things...

• Accuracy of focus.
  
• Accuracy of depth of field (aperature).
  
• The presence/absence of dust particles (which affect the results).
  
• The 5 primary images in which the results are based.

They can also run that file on their own system to ensure it gets identical results.

 

[Rhino]

R/T,




I have a database of approx. 30 or so 8*'s which I've tested. Drop me an email.

 

[niceice]

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On 1/19/2004 2:11:11 PM Rhino wrote:


R/T,


I have a database of approx. 30 or so 8*'s which I've tested. Drop me an email.
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Will do... Thanks Jonathan... And thanks for all of the insight that you have provided on this thread for people to review... Lots to read, lots to think about... It's probably time to let this thread rest because we're not sure that Leonid has the server space for it to continue for the rest of eternity

 

[Garry H (Cut Nut)]

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On 1/19/2004 2:07:12 PM Rhino wrote:

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On 1/18/2004 12:22:25 AM Rank Amateur wrote:



How does GemEx 'certify' a score without having the stone sent to them? Why not just send them the stone?
----------------

One reason I think Rank is becuase in the images you can see a number of things...

• Accuracy of focus.
• Accuracy of depth of field (aperature).
• The presence/absence of dust particles (which affect the results).
• The 5 primary images in which the results are based.

They can also run that file on their own system to ensure it gets identical results.

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But they can not test for or control a number of other possible deliberate missuses.

As a lab instrument it might have had a good chance when truly independant operators were involved.

We hope to accomplish that with the idealscope.
1. by letting buyers use it
2. by establishing a lab photo system that ensures that everyone takes the same type of photo.

 

[valeria101]

Garry, is yours the first device (aside the darn loupe or something) that costomers can use to reproduce/confirm themselves the results of light return tests on the diamonds they buy?

I have to say that, in theory, this approach (get the consuler to "certify") is one known solution to the otherwise endless game of trust of "who certifies whom" (shorthand for all that discussion about independent labs/appraisers and validating BScope results etc.). So I am quite curious if this rather straightforward approach to cut the Gordian knott had other versions prior to the hand-held scope. Hope this does not take your time...

 

[niceice]

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On 1/20/2004 2:11:58 AM valeria101 wrote:

Garry, is yours the first device (aside the darn loupe or something) that costomers can use to reproduce/confirm themselves the results of light return tests on the diamonds they buy?----------------

The ideal scope does not, nor have we ever heard Garry claim that it measures light return, rather it makes it possible for the user to determine how light is reflected by the facets of the diamond in similar fashion to the Fire Scope. We often see people incorrectly refer to the whiter areas of the diamond as seen through the Ideal Scope and other devices as "leakage" however the fact is that the diamond is not really leaking light in the sense that most people seem to think is being shown by the Ideal Scope. Rather what people are actually seeing are areas beyond the scope of the angle of light as diffused by the red / pink reflection of the cone inside of the Ideal scope... Change the angle of the cone, change the angle of the reflection, change the extent of the reflection, change the "leakage" as it is so often incorrectly called... This is not to say that Garry's invention is not useful, on the contrary! It shows how well the facets are aligned to reflect light back up through the top of the diamond... But just like the Brilliance Scope, there are scalability issues which can present a challenge to the inexperienced user, but with a little practice, the Ideal Scope can be a useful tool for those who take the time to become familiar with it's use... By "scalability" we are referring to the varying distance that each user might use to evaluate the same diamond... One user might view the diamond through the scope from a distance of one inch and somebody else might view it from half an inch while another person might view the same diamond from a distance of three inches and with each change in distance, the angle of the reflection of the colored cone changes and thus so does the view of the diamond as seen through the scope. No doubt that the entire premise behind the Ideal Scope and it's professional grade counterparts, the Fire Scope, SymmetriScope, Light Scope, would make an interesting thread of it's own. Note that we have not yet seen Garry's newest version of the Ideal Scope, we are basing our comments upon the original, less expensive version...

The thing to realize with the whiter areas which are usually visible along the edges of a diamond when viewed through the various instruments is that the pink / red areas are that color because that is the color that is being reflected off of the facets of the diamond... If the angle of the cone was changed, made shallower or steeper, then the degree to which the light reflects of the surface of the diamond would change and thus the extent of the white areas would also change... Likewise, if light reflected off of a pink surface was directed towards the diamond from the sides at the same time light was being reflected from the top of the diamond, you would see no white areas at all... And in the real world, light IS reflected from all sides of the diamond, isn't it?

 

[Garry H (Cut Nut)]

I think it probably is Val.

And it was always my intention.

Of course barring decietful supply of proportions, HCA does this too.

Now of course we can debate endlessly which technology is best / most accurate / cost effective etc

But I hope to be seen as a contributor to improving the cut quality of diamonds. It certainly is not making me rich though.

 

[niceice]

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On 1/20/2004 2:11:58 AM valeria101 wrote:

Garry, is yours the first device (aside the darn loupe or something) that costomers can use to reproduce/confirm themselves the results of light return tests on the diamonds they buy?----------------

Garry, we think that you might want to read this question again... We interpret it as asking whether the Ideal Scope can be used to verify / confirm the results of the Brilliance Scope (in accordance with the subject of this thread) and we really don't see how it can do that... What are we missing here?

 

[Superidealist]

I think any device that tries to pin a number on something as subjective as beauty is doomed to fail. I think the makers of these devices agree and so don't claim to measure a diamond's beauty but rather things like brilliance, fire, scintillation, and symmetry.

My problem with these devices is that most of the things they claim to measure are so nebulous that there doesn't seem to be much agreement as to what they actually are let alone how best to measure them. If the Brilliance Scope and Isee2 were content generate numbers without pretending that they were actual measures of the attributes they claim, I would have no problem with them. But they aren't and I do.

That doesn't mean they're useless, though. I just think they should be viewed in the same way as one would view a movie critic. A movie isn't great just because it receives 5 thumbs up, but if I usually agree with the reviewer's opinion, I might reasonably assume that it would be worth seeing.

 

[valeria101]

Thank you Garry and Nice Ice!

I am sorry that my question was not clear and made you get into so much typing. It was my question that did not follow the spirit of the thread closely: I merely intended to ask what Garry thought to reply. I surely am grateful or every bit of info I can get, as you may guess. Your comments are very much appreciated.

 

[niceice]

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On 1/20/2004 12:50:34 PM Superidealist wrote:

I just think they should be viewed in the same way as one would view a movie critic. A movie isn't great just because it receives 5 thumbs up, but if I usually agree with the reviewer's opinion, I might reasonably assume that it would be worth seeing.----------------

But the scary part about this is that we seem to like the movies that the critics hate and fall asleep watching the ones they liked

 

[valeria101]

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On 1/20/2004 12:50:34 PM Superidealist wrote:




If the Brilliance Scope and Isee2 were content generate numbers without pretending that they were actual measures of the attributes they claim, I would have no problem with them.


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Not that I believe that this thread needs further help from my part to get even bigger, but this sounds funny! If some device produces "numbers" which are not "actual measures of the attributes [it] claim" than why not take a pair of dice, toss it, inscribe the resulting score on a diamond girdle and call it something meaningful?

I am quite sure the citation above meant something else, but the actual message just could not escape a little "interpretation"

Please also accept my apologies, Superidealist.

 

[Superidealist]

I believe that both machines are measuring something and that that something is quite likely related, closely or not so, to the diamond's appearance. Is what's being measured brilliance, fire, scintillation, and symmetry? That's clearly what they are trying to measure, whether they say so or not, but who knows? Most of these terms are so ill-defined that there is no general agreement on how to measure them yet. (Hopefully that's changing.) Given this, I think it's a little premature to be claiming that the Brilliance Scope and Isee2 are measuring these attributes.

And to Robin and/or Todd: Even a bad critic's opinion can be helpful, as long as he is consistent and you know how his tastes compare to your own.

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On 1/20/2004 2:06:21 PM valeria101 wrote:

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If some device produces 'numbers' which are not 'actual measures of the attributes [it] claim' than why not take a pair of dice, toss it, inscribe the resulting score on a diamond girdle and call it something meaningful?----------------

 

[oume03]

I would like to add my $0.02. First off, I am a diamond newbie so as a warning some of my facts may be off but I think you will be able to understand the gist of my contribution.

Evaluating a diamond (when I say diamond, I will limit my discussion to a round brilliant cut) to compare with what a human perceives as beauty is very difficult as beauty as they say, is in the eye of the beholder. Therefore, statistically speaking, there is a specific diamond geometry, the Tolkowsky Ideal Cut, that most people find beautiful. What is needed is an accurate way of measuring the light interaction in a diamond giving it its beauty. Optics is a well-understood subject so one would assume that it would be easy to measure each facet of a diamond and model the optical behavior of the diamond in various lighting and observation schemes.

However, measuring the orientation of each facet could only be done with a lot of uncertainty because each facet location would include three degrees of freedom (meaning that it can move along the x, y, and z-axes) of measurement uncertainty. That means at a minimum, the diamond would have an optical model comprised of 58 facets containing 174 uncertain measurements. Not to mention inclusions, varying chemical compositions through the diamond (which affects the index of refraction), and the flatness of each facet, which would need to be included in an accurate optical model but are extremely difficult to measure and/or locate.

Therefore, building an optical model based only on measurements is next to impossible to do. So from what I can tell, the companies that manufacture the Brilliance Scope and Isee2 have tried to do is evaluate the diamonds optical performance by a holistic approach in a cost effective manner (which limits the complexity of the machine).

Admittedly, the measurements taken by either apparatus do not model the real world exactly but I do believe that they give a good idea of the expected optical performance of the diamond as it relates to a statistically determined value known as beauty and thus is a good metric for a buyer to use in the purchase of an unseen diamond assuming that the apparatus was used in a correct manner.

Assuming that the systems are used and calibrated properly I believe that they accurately and reliably indicate the value of their measurand based on my knowledge and use of CCD’s (read digital camera) in scientific applications which require high levels of sensitivity and repeatability. However, the systems’s measurements are correlated to beauty, a highly subjective measurand.

 

[Garry H (Cut Nut)]

Both machines favor symmetrical stones because of the two different types of lights they use.

GIA and AGS have both found that the human eye can not detect extremely high levels of symmetry (although there is a good arguement that high levels of perfection in symmetry are of value for values sake).

There is no agreement that any type of pixel counting software can as yet agree on the type or range of human taste and preference.

 

[strmrdr]

ugh this thread again. lol
Software/measurement based vs light/camera based systems.

Both have strengths and weaknesses and both are useful.
Which is better?
I dunno which is better an apple or an orange?

 

[JohnQuixote]

There are more recent threads that pose these questions.

 

[Slykat12]

Had To Jump in here! The topic being an extremely timely one for moi.

Ahem: My "hopefully" e diamond is a Marquise. It was cut according to AGA top 1A standards. The rock was tested with brillancescope and bombed big time. I know fancies don't return light as well as rounds blah blah blah. But, I have seen high and very high brillancescope ratings on several other Marquise stones all with widely varying cuts.

Hmmmm???


I was told that my Marquise has a small bowtie effect and this is good because to the eye it looks more attractive. However, on the brillancescope results it is not so good as light return is less with a small bowtie verses a big.

This kinda made sense but i am wondering what you all think as I am an information junky.

Thanky in advance

 

[strmrdr]

Date: 6/19/2005 10:24:40 AM
Author: Kimberly
Had To Jump in here! The topic being an extremely timely one for moi.


Ahem: My 'hopefully' e diamond is a Marquise. It was cut according to AGA top 1A standards. The rock was tested with brillancescope and bombed big time. I know fancies don't return light as well as rounds blah blah blah. But, I have seen high and very high brillancescope ratings on several other Marquise stones all with widely varying cuts.


Hmmmm???




I was told that my Marquise has a small bowtie effect and this is good because to the eye it looks more attractive. However, on the brillancescope results it is not so good as light return is less with a small bowtie verses a big.


This kinda made sense but i am wondering what you all think as I am an information junky.

Thanky in advance

Im no expert on them but when you say bombed what were the readings?
I would go for the smallest bow tie possible if it was me.
I hate the split in 2 look they get with bad bow ties.

How does the ideal-scope image look?
If the idealscope image backs up the b-scope then id keep looking.

 

[Slykat12]

"Im no expert on them but when you say bombed what were the readings?
I would go for the smallest bow tie possible if it was me.
I hate the split in 2 look they get with bad bow ties.
How does the ideal-scope image look?
If the idealscope image backs up the b-scope then id keep looking. "
The brillance scope results for the stone where med scint, med white, and high color. The ideal scope is here.
Sorry it won''t load.
Second down.

https://www.pricescope.com/community/threads/marquise-pics.29438/=

 

[strmrdr]

Date: 6/19/2005 10:46:43 AM
Author: Kimberly
''Im no expert on them but when you say bombed what were the readings?

I would go for the smallest bow tie possible if it was me.

I hate the split in 2 look they get with bad bow ties.

How does the ideal-scope image look?

If the idealscope image backs up the b-scope then id keep looking. ''

The brillance scope results for the stone where med scint, med white, and high color. The ideal scope is here.

Sorry it won''t load.

Second down.


https://www.pricescope.com/community/threads/marquise-pics.29438/=

is it rockdoc that did the b-scope?
What does he say about it?
The images look pretty good to me.

 

[Slykat12]

Thanky Stormrider on the scope opinion.

I was wondering if Rhino would chim in with his experiance on fancys, bowties and the bscope.

Opps did cali just have another earthquake?

 

[valeria101]

Date: 6/19/2005 11:33:20 AM
Author: Kimberly

I was wondering if Rhino would chim in with his experiance on fancys

Just adding to the question...

Once Upon a time, Good Old Gold was posting a database of sold diamonds with Iscope and Bscope reports. I still find it hard to belie that no one drew some statistics out of it

Upon casual examination the mentioned collection, it seemed that theBscope overstates the merit of reflector facets (black patches under the IS) and understates the merit of IS red zones ones for fancies, so there is some divergence between the two tools. Among round diamonds, you can''t really have one with mostly white and black under the IS, but this can happen for fancies and when it does that stone gets a high BS score and is rejected relative to the refference examples of the IS. It just so happens that I agree with theIS in this matter... butit wasn''t brought up. Before my last computer crash, I used to have a file with princess cut BS scores and IS pictures showing this.

The observation is consistent with the usual claim that the BS scores reflect "performance" in direct light conditions while the IS evaluation is less dependent on lighting.

Looking at the all-red IS of your Marq, it seems tomake a good example of the above.


Perhaps Jonathan would care to put the database to use on of these days

All it takes is a roughly qualified statistician vaguely familiar with empirical data and discrete scoring...

 

[Slykat12]

Val, said: "Perhaps Jonathan would care to put the database to use on of these days All it takes is a roughly qualified statistician vaguely familiar with empirical data and discrete scoring..."

I would volunteer to do that if gog was in los angeles as I gots stats smarts!

Thanks again Val as a fellow fancy lover I value your opinion.