AGS "0" & Sarin Data Vs. HCA vs. Brilliance Scope

[Richard Sherwood]

-----------
Richard-How are you doin? Haven't heard a word back
from you on this post. Are you busy soaking up that
florida sun?
-----------

Sorry Josh. I got tied up with a massive estate appraisal and preparations to land a (large) new account.

Nice work Josh. You sure got things buzzing. That's the first time I've seen Garry volunteer to send his golden calf out to somebody.

Tim, you amaze me. You are a serious computer guy.

Garry, if you ever decide to market the HCA, you can put me down on the list as a buyer. It would be a great informational tool to add into my appraisals. I routinely include the DiamCalc simulated IdealScope images now, along with the D.C. Light Return Analysis. It impresses that daylights out of the privates, and has floored the local dealers. They're all scrambling...

 

[Rhino]

Hey Josh,

I've already conducted studies like what you're doing and can point you to many examples demonstrating the info you're looking for. My site however is currently down. Tomorrow is an email catchup day for me and plan to knock em all out, then I catch up with scanning (I have a quite a few people waiting for me to finish up the posting of some stones). If you drop me an email however I'll send you links to multiple stones that'll greatly help you in your study.

Once the site is up you will want to see a 1.078ct E VVS2 which is in the "New Stones being scanned section" that I just posted up tonight. It scored 4 Excellent's on the HCA and I'm currently showing it to a client who's comparing it to a 1.06ct E VVS2 which you'll also find up there. The 2 make an interesting comparison as they are very similar except for the differences in the cutting of the minor facets. The lesson to be learned from the 2 stones is how the minor facets contribute to the overall brilliance and scintillation of the diamond when all other things are similar.

Email me and I'll send you more examples.

Peace,
Rhino

 

[Colored Gemstone Nut]

Thanks Jonathan-Since you have done some caomparison studies which are similiar to this one your input will be invaluable. I'll email you tomorrow.

Josh Rioux
Sitka, Alaska

 

[optimized]

Josh,

I'm really enjoying your little research project and am happy to help however I can.

Generating the chart of your stats initially caused me some problems since the IdealBB system disables a whole raft of useful HTML tags (including tables), but I overcame them in the end.

To begin, I copied and pasted the information (category by category so I could split the columns) into an Excel spreadsheet. I made up some quick headings and borders, then did a screen capture of the page and dumped it into an image editor. I had to do it in three parts (the chart is quite a bit longer than my 1024x768 settings would allow), but it was easy enough to stitch it back together in the editor. Finally, I cropped it for neatness, saved it as a GIF file to keep the size down, and posted it. Pretty easy project once I decided how to do it.

I'll be watching your progress as you go since I'm pretty interested in how the BScope and HCA correlate. I have some ideas for your project that I'll mention in a later post/email. I don't actually expect too many of them to be incorporated since the data is likely to become quite voluminous, but I'll throw them out there anyway.

Garry,

It's very nice of you to offer the app to Josh. If you're ever feeling especially magnanimous, I'd love a copy too (with the same guarantees Josh has already given). Don't worry though, I won't be offended if you don't want to spread your baby too thin by giving it out to everyone who asks.

I can understand your reluctance. Btw, as far as difficulties with keeping the app up-to-date after you've distributed it, you might consider either an auto-updating feature (not terribly reliable), or an automatically expiring version that would stop working until users re-downloaded new versions periodically (very reliable). I've had a couple apps in the past that utilized the latter method, and it virtually guarantees that users have the most current version of software (and allows you to change the licensing at a later date to a pay/subscription model if you choose).


Richard,

Thanks for the compliment. I do have fun with the image editors on occasion.

Btw, hearing about the work you (and others here on Pricescope) do, I start to get pretty envious of your job! I keep getting that itch for a career change!

I've been seriously considering it lately...


Jonathan,

I'd like to be in on that too, if you and Josh don't mind. Maybe you could post the info here. Thanks!


Boy, this is a pretty cool thread that's gotten going here, eh? I dig it....


-Tim

 

[optimized]

Wow, I appear to have gone "smiley happy." I'll have to work on that...

-Tim

 

[Colored Gemstone Nut]

----------------
On 2/21/2003 1:39:15 AM optimized wrote:
Josh,

I'm really enjoying your little research project and am happy to help however I can.

Generating the chart of your stats initially caused me some problems since the IdealBB system disables a whole raft of useful HTML tags (including tables), but I overcame them in the end.

To begin, I copied and pasted the information (category by category so I could split the columns) into an Excel spreadsheet. I made up some quick headings and borders, then did a screen capture of the page and dumped it into an image editor. I had to do it in three parts (the chart is quite a bit longer than my 1024x768 settings would allow), but it was easy enough to stitch it back together in the editor. Finally, I cropped it for neatness, saved it as a GIF file to keep the size down, and posted it. Pretty easy project once I decided how to do it.

Tim- I am still comparing and collecting data. I am also adding the sarin data to the documented stones. My dilemma is I have microsoft 98 and am quite proficient with the spreadsheet program. However I don't have the tech or knowhow to shrink the chart down to size and switch to a format which is acceptable in me being able to post my results as you did on this sight. ANy suggestions.

Leonid-Is there an easier way I could go about posting my charts with out all the going through the different hoops of shrinking data and putting it in a different format.?

Garry-Hopefully you received my email from my hotmail account. I sent it yesterday. Heep me posted?

-Josh RIoux
Sitka, ALaska

----------------

 

[Colored Gemstone Nut]

Hey Garry-I received the program you sent containing the HCA. I have some questions though on current scoring. I am realizing that there are some variations from the existing scoring with the(HCA) desktop program you sent me vs. the online addition. Has it been updated which accounts for the more stringent scoring & also accounting for girdle thickness % which previously has not been a part of the online version?

-Josh RIoux
Sitka,Alaska

 

[Garry H (Cut Nut)]

The HCA you have has been updated.
We do not think online people can easily always get girdle thickness % so we work it out on the fly frrom depth % minus culet, pav depth and crown height in the online version Scorpion.

 

[Colored Gemstone Nut]

Hey-This questions goes out to everyone that might have available data that could help out. I am currently in the process of charting 100 stones for the comparison. I would like to add some additional depth to the comparison by including
stones and showing correlations of BScope/HCA from beautiful cuts that fall outside the AGS0 scale. If any reputable individual has any examples with viable date which includes bscope readings and sarin results that fit that description would you please offer some assistance as I would like to add it to the charts I will be posting when I'm finished with them.

Thanks-Josh RIoux
Sitka, Alaska

 

[Colored Gemstone Nut]

Hey Rich-Here's the actual megascope measurements for this stone. I will be attching images of the scans for the Internal cut and also Firescope image. Diamond scores VH3 white light/vh3+colored light/h2 for scintillation on the b-scope. Excellent stone overall. Let me know what ya think?

----------------
On 2/16/2003 2:47:59 PM Richard Sherwood wrote:

Josh, this should be an incredible stone. I've attached a DiamCalc simulated IdealScope image as another "check" in addition to the HCA scores, etc.

The Light Return Analysis comes out with "very goods" across the board, which is about the best you will see:

Light Return Mono.......Very Good 0.99
Light Return Stereo.....Very Good 0.98
(Non) Leakage Mono......Very Good 0.97
(Non) Leakage Stereo....Very Good 0.98
Contrast................Very Good 0.97
(Non) Fisheye Effect....Very Good 1.00

Wow.

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IdealScope- In general, the darker pink areas indicate areas of greater light return, with the lighter pink areas indicating areas of lesser light return. The black areas indicate areas of greater contrast, with the gray areas indicating areas of lesser contrast. The white areas indicate areas of light leakage. A good explanation of the IdealScope image along with examples can be found at http://www.pricescope.com/idealscope_indx.asp

Disclaimer- The facet arrangement and symmetry of the image will probably vary from your actual diamond, which may affect the light performance indicated. The computer simulation is reproduced best when the actual diamond is being viewed and the image "tweaked" to the appearance of the diamond. However, this "blind" reproduction should be helpful on the major light performance aspects.
---------------------------

Josh RIoux Sitka, Alaska

 

[Colored Gemstone Nut]

Hey Again Rich HEre's a scan of the internal cut. It scores a .6 overall on the HCA. Light Return/0,Fire/.10,Scint/.11,Spread/.20 Excellent within TIC. I have been advised that one of the hearts is as symettrical as the other hearts on the stone, but overall a brilliant stone even though not perfectly proportioned. Sweet Huh...

 

[Colored Gemstone Nut]

Additional Image

 

[Colored Gemstone Nut]

And finally the arrows image. Its kind of fun to compare the images to diamoncalc huh....

 

[Richard Sherwood]

Sweet...

I went back and compared the "blind" IdealScope image with the real image (which looks to be a LightScope image?), and was impressed with how close the DiamCalc program came to the real thing. The real image looks even better though.

Those numbers are really great Josh. Nice work.

 

[canadianice]

Scorpion -
Is this the same stone used to start the thread? It appears to be by carat weight, colour and clarity.

If so, why are the crown and pavilion angles different in the Sarin report, versus those originally listed? How do the new numbers add up in the DiamCalc compared to the original?

Also, I'm confused - can an AGS "0" have a "2" grade for pavilion depth????

Irregardless, great lightscope image!

 

[Rhino]

Greetings!

As per request of some on this thread I'd like to include some data that will help in the understanding of this topic. This is the tip of the iceberg but will help (I hope) in the understanding of trying to correlate the data you are attempting to do. More of this will be expounded upon more fully on my page of the minor facets once I finish it.

Earlier in this thread I mentioned 2 stones I've which have very similar primary proportions whose major differences lie in the minor facets.

This first example is a 1.078ct E VVS2 which scores a .9 HCA and 4 Excellents.

Here are 2 images of the same stone. One taken under our LightScope (image on the left) and the same exact stone taken under another scope that duplicates FireScope results.

This is a diamond whose

a. star/lower girdle facets are of the shorter flavor
b. upper girdles angles have been cut to eliminate blatant leakage.

LightScope reveals that the leakage that has been eliminated (while a good thing) is returning light albeit weak light (as indicated by the pale reds). The shorter star/lower girdle combo also minizes or completely eliminates hot spots (or blacks) between the arrows. Areas of black within the stone accentuate portions of the pavilion that reflect back some of the most intense areas of light. This can be seen, confirmed and verified in both BrillianceScope results AND DiamCalc animated models. This can also be observed by both laymen and gemologist in the analogue B'scope viewer as well.

 

[Rhino]

oops... forgot the image

 

[Rhino]

These are the sarin/mega results.

 

[Rhino]

These are the BrillianceScope results.

 

[Rhino]

This next stone is a 1.06ct F VS1. Here are the dimensions. This diamond scores HCA 1.1 with 3 Excellents and 1 Very Good.

 

[Rhino]

Our proprietary LightScope analysis reveals a greater saturation of dark reds PLUS more blacks.

What we are observing here is not just the quantity of light being returned the eye but the quality or intensity of it as well. There are less blacks and more pale reds in the stone on the right. The H&A stone on the left is of the longer star/lower girdle flavor. This kind of stone accentuates and creates the presence of hot spots (blacks) between the arrow head and also the arrow shafts (this is the equivalent of MORE mirrors being positioned in your face).

Let me also state this. You're talking to a very anal retentive diamond buyer here and I am splitting hairs that alot of people wouldn't bother doing. Not only is this my biz but it is also my passion and this geeky stuff fascinates me.

Many of my clients have visibly seen the differences between these 2 flavors.

Some pick one, some pick the other, alot don't care as long as it's a screamer.

THEY ARE BOTH BEAUTIFUL STONES. I just wanted to make that clear. I purchase both flavors for stock and encourage both types. I LOVE VARIETY.

Rhino

 

[Rhino]

These are the BrillianceScope results of this 1.06ct F VS1.

This demonstration also points out why the minor facets are extremely important in an overall optical analysis. I love the HCA as much as the next guy does but a system that does not take into account 40 out of 57-58 facets is leaving out too much data IMO. This is one reason why RockDoc has problems with the HCA.

I say take it all in stride and I would have to agree with GIA's comments when they say "There is NO ONE set of proportions that are BEST". Compare, when possible all these beautiful kind of stones side by side and make an educated decision.

Peace,
Rhino

 

[Colored Gemstone Nut]

Robin & Todd-Hey you guys. Glad to see you finally decided to add your opinion in the following qoute from another thread:

We have a lot of respect for the developers of the HCA and the BS but nothing beats a good set of eyes. We've rejected diamonds for lacking in visual performance which scored great "on paper" on the HCA and kept others which scored poorly... Hey, it's a work in progress not an absolute indicator, but we would like to add that the HCA just seems to be getting better and better with time. The same goes for the BS in our opinion, it is an indicator of potential, not an absolute defining factor. A lot of the problem with the BS lies not with the equipment, but with the user and how they have calibrated the machine.

I AM EDITING THIS PORTION BECAUSE FOR SOME REASON LAST NIGHT ALL MY INFO WASN'T POSTED ON THE THREAD. ROBIN & TODD INTERESTING ENOUGH, I HAVE BEEN ALSO IN CORRESPONDANCE WITH RICHARD FROM EIGHTSTAR & I CANNOT COMMENT OR POST HIS QUOTE, BUT HE IS NOT AN ADVOCATE OF THE B-SCOPE.I POSED THE SAME QUESTION TO SEVERAL DIFFERENT PROFESSIONALS AND WILL POST THEIR RESPONSES IF THEY ARE WILLING TO PARTICIPATE IN THE THREAD. THE QUESTION I ASKED IS "IN ALL YOUR YEARS OF EXPERIENCE WHAT DO YOU THINK IS THE BIGGEST DETERMING FACTOR IN A STONE RECEIVING VERY HIGH SCORES IN ALL CATEGORIES OF THE B-SCOPE. I HAVE ALSO WRITTEN THE CEO OF GEMEX AND HAVE YET TO GET A RESPONSE, BUT WILL POST IF HE PARTICIPATES. I HAVE ALSO BEEN CORRESPONDIING WITH BRIAN "THE CUTTER" FROM A CUT ABOVE HEARTS & ARROWS DIAMONDS & HE HAS ASSURED ME HE WOULD LIKE TO PARTICIPATE ON THE THREAD AND VOICE HIS OPINIONS ON THE MATTER. IT SHOULD BE INTERESTING TO HEAR WHAT HE HAS TO SAY CONSIDERING THAT COMPANY IS NO LONGER USING THE B-SCOPE IMAGES IN MARKETING THEIR PRODUCT. I WOULD ALSO LIKE TO ADD THAT GARRY'S NEW UPDATED VERSION OF THE HCA SEEMS TO BE ADJUSTING ITS PARAMETERS FOR "SPREAD" IN THE NEW VERSION STONES WHICH SCORED VERY GOOD FOR SPREAD ARE ALL NOW SCORING EXCELLENT.

MORE-LATER-TIRED AND NEED TO GO TO BED

JOSH RIOUX
SITKA, ALASKA

 

[optimized]

Wow, I go out for the evening and the thread just TAKES OFF while I'm away! LOL!

Jonathan,

Are these stones listed on your site at all? While it's great that you're listing the information here for us to see, I'd be interested in seeing them in their "native habitat" as well...

-Tim

 

[scotch]

Scorpionrioux, Rhino,

comparing Rhino's two diamonds is extremely interesting: The 1.078ct is of the "tweaked girdle" type, as are 8star and A Cut Above, among others, while the 1.06ct is of the "standard girdle" type, such as e.g. SuperbCert. It seems the tweaked girdle stones typically score H/VH/H on the Brilliancescope, while well-proportioned "standard girdle" brilliants can score VH/VH/VH. Richard von Sternberg has given his reasons why he doesn't endorse the Brilliancescope before (see: http://www.diamondtalk.com/forums/showthread.php?threadid=1833) . It seems Brian the Cutter has come to the same conclusion, it remains to be determined what this says about their product, or about the Bscope, for that matter. I will try to feed Rhino's two diamonds into DiamCalc over the weekend, and see what the results are. I have a suspicion about the outcome, though: I would expect that the standard girdle diamond will score slightly higher on light return, while somewhat weaker on light leakage and especially contrast. I have found in the past that tweaked girdle diamonds come out better in contrast and light leakage (particularly 8stars are optimised for light leakage under the Firescope, after all), while they are not as high in light return.

I wonder if it is true that Gary Holloway, "the Russians" (Serg and his crew), and Brian worked together in developing the "A Cut Above" diamond. It would be interesting to hear from them why they decided to make it with a tweaked girdle, and what role DiamCalc played in the development, as well as how they interpret the Bscope results. If Gary, Serg and Brian have in fact collaborated in developing the ACA, it would be logical to assume that there will be a high correlation between high HCA and DiamCalc scores, as well as with good IdealScope/ Firescope results. On the other hand, a VH/VH/VH Bscope score would not show much (positive) correlation with the other scores. Is my logic flawed, or does everybody know this already?

Scotch

 

[Colored Gemstone Nut]

----------------
On 2/28/2003 12:21:26 PM scotch wrote:

Scorpionrioux, Rhino,

comparing Rhino's two diamonds is extremely interesting: The 1.078ct is of the "tweaked girdle" type, as are 8star and A Cut Above, among others, while the 1.06ct is of the "standard girdle" type, such as e.g. SuperbCert. It seems the tweaked girdle stones typically score H/VH/H on the Brilliancescope, while well-proportioned "standard girdle" brilliants can score VH/VH/VH. Richard von Sternberg has given his reasons why he doesn't endorse the Brilliancescope before (see:

Scotch----------------

Scotch I am attaching a qoute from an earlier thread inquiring about 8-star b-scope readings along with an actual 8 star b-scope reading which take into account the hit they take in the white light and scintillation dept. . The following qoute is from RockDoc:



I have seen quite a few eightstars here in my lab.

What you need to consider is the difference in the appearance of the stone versus the other competeing diamonds.

I will tell you that I haven't yet seen any of the new line ACA stones from Whiteflash, although they have agreed to send a sampling of their stones for me to take a snoop at.

The Eighstar diamonds do have incredibly intense dispersion. Often they "face up" more colorless than their color grading.

The basic difference is that the dispersion is broad coloration being returned to the eye, but to achieve this you trade off a slight bit of scintillation and brilliance.

The other H&A stones often have a similar amount of dispersion, but the color areas are smaller as eightstars are cut with small star facets and larger upper girdles facets.

It's basically a matter of your preferences,what you expect appearance wise, and of course - budget.

Each cut has its pros and cons... as the balance of white light, dispersion, and scintallation are compared.


Rockdoc

Richards diamonds are ALL cut to short star/lower girdle combos. There are combinations within the minor facets that produce more optically pleasing results. Might it be the fact that because of the unique look of eightstar & because of those short star/lower girdle combos it takes a hit on the b-scope. And because of the hit it takes it's followed by Eight-Star not endorsing the b-scope..Hm...Definitely raises some questions. Richard is definitely a pioneer in the industry, but I think credit should be given where credit is due when it comes to the b-scope.

-Josh Rioux
Sitka, Alaska

 

[Rhino]

----------------
On 2/28/2003 1:22:57 AM optimized wrote:


Wow, I go out for the evening and the thread just TAKES OFF while I'm away! LOL!

Jonathan,

Are these stones listed on your site at all? While it's great that you're listing the information here for us to see, I'd be interested in seeing them in their "native habitat" as well...

-Tim


----------------

Yes they are optimized.

 

[scotch]

Here are the DiamCalc results for Rhino's 1.06ct (standard girdle) stone:

Light return mono: 1.01
Light return stereo: 0.99
Light leakage mono: 0.97
Light leakage stereo: 0.95
Contrast: 0.90

Assumptions for this stone: Star facet length 60.7%, lower girdle facets 78%.

The results for the 1.078ct (tweaked girdle) stone:

Light return mono: 0.99
Light return stereo: 0.97
Light leakage mono: 1.00
Light leakage stereo: 1.02
Contrast: 1.08

Assumptions for this stone: Star facet length 60%, lower girdles 77.9%.

Some pictures are to follow, the real LightScope photos are courtesy of GoodOldGold

.

Scotch

 

[scotch]

Here is the DiamCalc simulated Firescope pic of Rhino's 1.06ct E VVS2 stone:

 

[scotch]

Here is the real LightScope photo: