What procedures to follow when reflectors cannot (any longer) help?

[strmrdr]

fwiw I believe, no make that I know, you can design some bad diamonds using ASET as your only criteria.
Even AGS does not use it as their only criteria.
That is why you can not get the AGS grade by looking at a diamond under the ASET scope.

 

[Serg]

Date: 8/3/2009 4:51:27 PM
Author: Garry H (Cut Nut)

Date: 8/3/2009 4:26:14 PM

Author: Serg

Date: 8/3/2009 4:22:02 PM

Author: Stone-cold11

Date: 8/3/2009 4:19:00 PM


Author: Serg



No. Bad diamond could have zero leakage, good RBC diamonds have some leakage



Of course usually diamonds with big leakage are bad, but one time I saw nice for me diamond with huge Leakage and Huge Fire in same time. Garry saw it too

Do you have the proportions for that? Sounds interesting.

No. I saw it in Diamond Found( Moscow Kremlin), I can not receive it to scan .

It was a little unusual Sergey - it was rather large

http://images.google.com.au/images?sourceid=navclient&rlz=1T4GGLL_en&q=orlov+diamond&um=1&ie=UTF-8&ei=l013SrWCKsyQkQXUpbyEDA&sa=X&oi=image_result_group&ct=title&resnum=4

Garry, Diagem
it was different diamond.
it is :
1) loose diamond
2) Seems it is Stepcut type but with unparalleled opposite facets
3) 20-30ct
4) right conner in left window in last room

 

[Garry H (Cut Nut)]

Date: 8/3/2009 11:35:55 AM
Author: John Pollard

Date: 8/2/2009 2:16:16 AM
Author: Garry H (Cut Nut)
Sergey i think this slide from http://www.gemology.ru/cut/english/conferens-article/fig5b.htm is more appropriate.

Garry,

Have you taken this to a VF level and considered dominant hues in terms of DCLR? Or is this strictly relative to grayscale/obstruction?

Hi John, I did not entirely get your question?

 

[strmrdr]

Date: 8/3/2009 4:57:47 PM
Author: Garry H (Cut Nut)


For cut desiging Storm you could include more colours in smaller graduations

There is one feature I wish DC had, the ability to overlay VF's aka draft + double reflection over the photoreal images in real time.

 

[Garry H (Cut Nut)]

Date: 8/3/2009 5:28:53 PM
Author: strmrdr

Date: 8/3/2009 4:57:47 PM
Author: Garry H (Cut Nut)


For cut desiging Storm you could include more colours in smaller graduations

There is one feature I wish DC had, the ability to overlay VF''s aka draft + double reflection over the photoreal images in real time.

You can design your own structured lighting in DC Storm.
The manual has a 5 or 10 page section on how to do it.
You can also make an HDR image and use that

 

[diagem]

Date: 8/3/2009 4:57:47 PM
Author: Garry H (Cut Nut)

Date: 8/3/2009 4:50:52 PM
Author: strmrdr

Date: 8/3/2009 4:30:18 PM
Author: DiaGem
I saw this many times..., usualy when huge leakage is tilted (enough) it produces a huge flash of fire..., these exhibit a lot in the super shallow (40''std%) old-cuts...

often the greatest blast of fire is when a facet is either leaking or obstructing then switches to returning light.
The larger the VF the larger the effect.
I take this into account when designing asschers.
By carefully paying attention to face up patterns to integrate them into the design you can create some stunning diamonds.
The face up static brightness is impacted that is the price you pay.
I will trade off some brightness for kewl patterns any day.

To me RB''s don''t work that way they are all about brightness and light return.
No matter what you do the kewlest pattern is going to be arrows and to much of a good thing means a dark table.

When aset first came out I was thrilled with the concept in practice not so much as it does leave a lot of information out.
I do not design asschers using ASET and just check it when the design is almost done.
I may take the info the ASET does provide and tweak it a little but that is about it.

Storm and DG - the brightest flashes work their way from off, to blue, thru bright white, to orange red to off again, or in the opposite direction. This need not come off a background of leakage - it is simply that the facet is directing your eye to the lights.

For cut desiging Storm you could include more colours in smaller graduations

Depending on the shape and the viewing direction..., every facet will display leakage at a certain critical angle...

I am jealous you got a day-trip to the Kremlin Diamond fund..., hopefuly we can have a GTG in the near future at the Central Bank of Iran

.

 

[diagem]

Date: 8/3/2009 5:27:25 PM
Author: Serg

Date: 8/3/2009 4:51:27 PM
Author: Garry H (Cut Nut)

Date: 8/3/2009 4:26:14 PM

Author: Serg

Date: 8/3/2009 4:22:02 PM

Author: Stone-cold11

Date: 8/3/2009 4:19:00 PM


Author: Serg



No. Bad diamond could have zero leakage, good RBC diamonds have some leakage



Of course usually diamonds with big leakage are bad, but one time I saw nice for me diamond with huge Leakage and Huge Fire in same time. Garry saw it too

Do you have the proportions for that? Sounds interesting.

No. I saw it in Diamond Found( Moscow Kremlin), I can not receive it to scan .

It was a little unusual Sergey - it was rather large

http://images.google.com.au/images?sourceid=navclient&rlz=1T4GGLL_en&q=orlov+diamond&um=1&ie=UTF-8&ei=l013SrWCKsyQkQXUpbyEDA&sa=X&oi=image_result_group&ct=title&resnum=4

Garry, Diagem
it was different diamond.
it is :
1) loose diamond
2) Seems it is Stepcut type but with unparalleled opposite facets
3) 20-30ct
4) right conner in left window in last room

This is an amazing gem that I have..., its at 45%td and the flashes it shoots are incredible

.

 

[diagem]

Another try....,

ETA..., I will try to get an ASET on this baby tomorrow...., I wonder how BAD it will look...

 

[Garry H (Cut Nut)]

Date: 7/31/2009 4:17:03 PM
Author: Serg
dmc file for upper image

FYI Andrey fixed this file if anyone wants it.
It can be found on about the 6th post on page 4

 

[diagem]

Date: 8/3/2009 5:51:30 PM
Author: DiaGem
Another try....,

ETA..., I will try to get an ASET on this baby tomorrow...., I wonder how BAD it will look...

 

[stone-cold11]

Garry, regarding the pears you used for comparison of the ASET.

Is the best performer a different cut from the traditional pears? Off center culet? The other 3 pears' ASET/IS are more common from what I have seen.

Thanks.

 

[Serg]

Date: 8/4/2009 11:05:51 AM
Author: Stone-cold11
Garry, regarding the pears you used for comparison of the ASET.


Is the best performer a different cut from the traditional pears? Off center culet? The other 3 pears'' ASET/IS are more common from what I have seen.

Thanks.

Off center culet usually is very helpful for Pear Cut( D-Z and specially Fancy color)

 

[stone-cold11]

Thanks.

 

[Rockdiamond]

Date: 8/3/2009 2:46:03 PM
Author: Rockdiamond

Date: 8/3/2009 11:06:50 AM
Author: oldminer
I have yet to see a round diamond where the reflector image indicated a fine stone and the diamond appeared to look ''off'' or ''not excellent''.
I have not yet seen a diamond which had a ''fair'' reflector image yet which looked even close to anything like and ''excellent'' cut

It is possible to make naive consumers initially believe they don''t see much difference between such stones, ''fair-good- excellent'' especially when viewed in strong store type overhead lighting, but when the stone becomes a bit dirty or when the lighting becomes more normal, then the customer begins to understand the benefit of what screening with reflector techniques offered them. By then, it is too late. Of course there are borderline diamonds, ''good to very good'' which look very nice and are not super fine with reflector images. Anyone might choose such a stone for a consideration. Just as one might take an H color in place of an F or G color when it comes down to the final choice where the budget is part of the equation.

HI David- are you saying that you loved every stone with a better ASET as compared to others with lesser ASET''s?
Well, that''s your taste, and your right.
Remember, what you think looks ''excellent'', is not going to necessarily be the same as what I , or others see.

It seems to me that you performed a Sarin test and generated the images of the stones in my thread.
Would you consider the ASET of the .54ct ( photo attached) to be ''fair''

In terms the other part of your statement ( the second paragraph)- that''s nothing but, excuse me, a scare tactic.
Most people I know can tell if they are looking at something under a bright light.
I am a strong advocate in making sure people get a money back guarantee, so that they can take their time to evaluate a diamond purchase- in their normal lighting environment.

Where are these stones that , once they get dirty go from being amazing to ugly.
Or conversely, where are these reflector stones who look the same when they get dirty?
Reflectors do NOTHING at all to protect people from diamonds that may look lesser once they are dirty.....every diamond looks less shiny if it''s covered in dirt...which does not mean it looks ugly, or that all of a sudden the consumer will hate the stone they loved before.

Maybe it''s possible for you to ''make naive consumers'' believe things you want them to.
But in fairness, can''t we give a little credit to people shopping?


Garry- I''ll be more than happy to try with a few fancy shapes.

I don''t know if I missed this part- but has anyone knowledgeable with ASET evaluated the ASET I posted?

 

[Serg]

Date: 8/3/2009 2:46:03 PM
Author: Rockdiamond

Date: 8/3/2009 11:06:50 AM

Author: oldminer

I have yet to see a round diamond where the reflector image indicated a fine stone and the diamond appeared to look 'off' or 'not excellent'.

I have not yet seen a diamond which had a 'fair' reflector image yet which looked even close to anything like and 'excellent' cut


It is possible to make naive consumers initially believe they don't see much difference between such stones, 'fair-good- excellent' especially when viewed in strong store type overhead lighting, but when the stone becomes a bit dirty or when the lighting becomes more normal, then the customer begins to understand the benefit of what screening with reflector techniques offered them. By then, it is too late. Of course there are borderline diamonds, 'good to very good' which look very nice and are not super fine with reflector images. Anyone might choose such a stone for a consideration. Just as one might take an H color in place of an F or G color when it comes down to the final choice where the budget is part of the equation.

HI David- are you saying that you loved every stone with a better ASET as compared to others with lesser ASET's?

Well, that's your taste, and your right.

Remember, what you think looks 'excellent', is not going to necessarily be the same as what I , or others see.


It seems to me that you performed a Sarin test and generated the images of the stones in my thread.

Would you consider the ASET of the .54ct ( photo attached) to be 'fair'


In terms the other part of your statement ( the second paragraph)- that's nothing but, excuse me, a scare tactic.

Most people I know can tell if they are looking at something under a bright light.

I am a strong advocate in making sure people get a money back guarantee, so that they can take their time to evaluate a diamond purchase- in their normal lighting environment.


Where are these stones that , once they get dirty go from being amazing to ugly.

Or conversely, where are these reflector stones who look the same when they get dirty?

Reflectors do NOTHING at all to protect people from diamonds that may look lesser once they are dirty.....every diamond looks less shiny if it's covered in dirt...which does not mean it looks ugly, or that all of a sudden the consumer will hate the stone they loved before.


Maybe it's possible for you to 'make naive consumers' believe things you want them to.

But in fairness, can't we give a little credit to people shopping?



Garry- I'll be more than happy to try with a few fancy shapes.

David,

I advice you to stop publish this misleading ASET image
this image does not match with real diamond due Huge mistake in Sarin 3D model

You need receive better scan for this diamond or real ASET photo for this diamond( better to receive both its)


Until you do it you can not use this example to proof weakness ASET technology

It is very pity what David send this scan you.

 

[Rockdiamond]

My sincere apologies Serg!
This is the first time I''ve been advised the ASET image was defective!

I can have another scan run ( if the stone is still here, I''ll need to check)
Can you suggest someone in NYC who can run the scan?

 

[diagem]

Date: 8/4/2009 10:11:06 AM
Author: DiaGem

Date: 8/3/2009 5:51:30 PM
Author: DiaGem
Another try....,

ETA..., I will try to get an ASET on this baby tomorrow...., I wonder how BAD it will look...

The DC AIH trio..., IRL its amazing!

 

[diagem]

A frame of the IRL image....

 

[strmrdr]

Date: 8/4/2009 5:30:22 PM
Author: DiaGem

Date: 8/4/2009 10:11:06 AM

Author: DiaGem

Date: 8/3/2009 5:51:30 PM

Author: DiaGem

Another try....,


ETA..., I will try to get an ASET on this baby tomorrow...., I wonder how BAD it will look...

The DC AIH trio..., IRL its amazing!

neat
That is a perfect candidate for mounting a ruby under the window and let the red reflect throughout the diamond.
or a blue zircon even :}

 

[Regular Guy]

Date: 8/4/2009 5:20:43 PM
Author: Rockdiamond
My sincere apologies Serg!
This is the first time I''ve been advised the ASET image was defective!

I can have another scan run ( if the stone is still here, I''ll need to check)
Can you suggest someone in NYC who can run the scan?

David, not sure...but Jon at GOG absolutely has the equipment for a scan, using helium. I''m guessing, as Serg has suggested:

"You need receive better scan for this diamond or real ASET photo for this diamond( better to receive both its)"

he can do both, a real photo and the scan.

Is Long Island too far?

 

[Rockdiamond]

Date: 8/4/2009 9:42:05 PM
Author: Regular Guy

Date: 8/4/2009 5:20:43 PM

Author: Rockdiamond

My sincere apologies Serg!

This is the first time I''ve been advised the ASET image was defective!


I can have another scan run ( if the stone is still here, I''ll need to check)

Can you suggest someone in NYC who can run the scan?

David, not sure...but Jon at GOG absolutely has the equipment for a scan, using helium. I''m guessing, as Serg has suggested:


''You need receive better scan for this diamond or real ASET photo for this diamond( better to receive both its)''


he can do both, a real photo and the scan.


Is Long Island too far?

Not all that far.....To say nothing of the fact I''d love to meet Jon!

But it might be more expedient if we either got the equipment- or possibly find a way to test other stones if people requested.

We have access to a sarin, no problem there....

BTW- Diagem- what an amazing diamond!

 

[Regular Guy]

Date: 8/4/2009 10:26:04 PM
Author: Rockdiamond

We have access to a sarin, no problem there....

Sorry, David, is there a problem of any kind?

 

[Garry H (Cut Nut)]

Date: 8/5/2009 1:20:31 AM
Author: Regular Guy

Date: 8/4/2009 10:26:04 PM
Author: Rockdiamond

We have access to a sarin, no problem there....

Sorry, David, is there a problem of any kind?

Just a real photo Ira

David here is how - use a small lens camera like a canon Ixus with the hand held ASET (which I am sure you must have, and if you have not got a $50 ASET then we are really all banging our head against a brick wall).
http://www.ideal-scope.com/1.taking_IS_photos.asp

 

[DiamondFlame]

DG, I just want to say: WOW! What a fabulous looking diamond!

It would be interesting to see how a colored gem mounted beneath it, as suggested by Strm, would influence the way it looks. I'm just wondering if this could be done via a computer simulation...

Reflector technology certainly has its uses but it is still a tool. In the hands of an inadequately trained or inexperienced individual, without understanding its limitations, its usefulness may become a hindrance. While I agree that light return may be objectively measured, the concept of beauty is very much subject to personal preferences and therefore subjective. Not everyone loves H&A; different people just appreciate different patterns of light distribution in a diamond diffferently.

But thanks for sharing, guys! An eye-opener of a thread.

 

[John P]

Date: 8/3/2009 1:05:12 PM
Author: DiaGem

Date: 8/3/2009 11:24:11 AM
Author: John Pollard

Date: 7/30/2009 1:04:28 PM
Author: strmrdr

This is also why when looking at diamonds under the aset live you should tilt them back and forth.
When a round brilliant is said to have contrast issues it is a diamond that has persistent dark zones over distance.

You and DG both hit on this. Movement is critical, especially when you get away from brilliants. Diamonds are dynamic, it’s “what they do.”

The AGS LP takes a range of tilt into account; ASET views at 1 degree increments (14 degrees I believe?). That somewhat addresses the situation but it’s rarely mentioned - I suspect a lot of people don’t even know it’s a part of the assessment.

What I wonder is how effective or practical is it? Has anyone submitted a diamond of EX/Ideal standing and, because of tilt, had it disqualified? 14 degrees was chosen for a practical reason (FE/Girdle-ref). Ok. But is that practical in terms of performance qualities?

Yes..., good question.
Especially because its all pretty much systematic...
A ''systematic'' shape, facet design, angle combo, uniformed appearance, lighting, and (1-14 deg.) tilt...

I believe its way to systematic...
At least movement should be free-play...

Which is why most systems are static, face-up only. And even then there is variability/disagreement on fundamentals like obstruction, viewing distance, etc etc.

 

[John P]

Date: 8/3/2009 5:27:34 PM
Author: Garry H (Cut Nut)

Date: 8/3/2009 11:35:55 AM
Author: John Pollard

Date: 8/2/2009 2:16:16 AM
Author: Garry H (Cut Nut)
Sergey i think this slide from http://www.gemology.ru/cut/english/conferens-article/fig5b.htm is more appropriate.

Garry,

Have you taken this to a VF level and considered dominant hues in terms of DCLR? Or is this strictly relative to grayscale/obstruction?

Hi John, I did not entirely get your question?

I was on the fly Garry, sorry. To elaborate: Have you studied these tendancies in colors as well - what your eyes see individually as opposed to together? It would seem to have an impact on scintillation; what one perceives in stereoscopic vision as opposed to monoscopic models.

 

[Garry H (Cut Nut)]

Date: 8/5/2009 2:23:33 PM
Author: John Pollard

Date: 8/3/2009 5:27:34 PM
Author: Garry H (Cut Nut)

Date: 8/3/2009 11:35:55 AM
Author: John Pollard

Date: 8/2/2009 2:16:16 AM
Author: Garry H (Cut Nut)
Sergey i think this slide from http://www.gemology.ru/cut/english/conferens-article/fig5b.htm is more appropriate.

Garry,

Have you taken this to a VF level and considered dominant hues in terms of DCLR? Or is this strictly relative to grayscale/obstruction?

Hi John, I did not entirely get your question?

I was on the fly Garry, sorry. To elaborate: Have you studied these tendancies in colors as well - what your eyes see individually as opposed to together? It would seem to have an impact on scintillation; what one perceives in stereoscopic vision as opposed to monoscopic models.

DiamCalcPro has a stereo button for light return, contrast and all sorts of other functions John.
As you can see it also runs the computations for any number of parametric variations that you can choose right down to any minor facet.
That is why Sergey has spent so much time and effort studying these human variabilities.

There are many fire options too - but these can take a long time to run.

 

[Garry H (Cut Nut)]

Here are some others John, with different parametric variants set as part of what you might do to optimize an old cut with round to cushion shaped and variants of lower girdle.
It will produce images in what ever is on the main screen for every proportion combination as well as all the data which you would then place into charts.
What I just set up wiould take 3 days (it tells you after a few minutes) and will produce in this case about 50,000-100,000 numbers.

It is a very powerful tool and in relevance to this topic - it could be used by anyone to make a cut grading system for any cut of diamond (way more parameters than AGS use). However Sergey is far to rigorous to do this, and will not do so until a Master Stone Study has been completed that allows for detailed testing of the DC outputs against human perception.