Why would anyone object to painting?

[strmrdr]

Date: 6/13/2006 11:11:05 PM
Author: aljdewey

Date: 6/13/2006 10:59:59 PM

Author: strmrdr



lol

Thank you for the well wishes.

You''re welcome.

I STILL want some of the Vicodin. How''s about a nice game of Rock, Paper, Scissors for it? LOL

Sowwy gotta go to the dentist for me then ya can have some!


That reminds of a news story of a judge who ordered 2 lawyers to play RPS to settle an issue or get thrown in jail for contempt that I read the other day.

 

[JohnQuixote]

Date: 6/13/2006 12:04:38 PM
Author: Capitol Bill
Storm,

You''re right. The DD is not the issue. The issue is that the GIA is offering the DD as a definitive way to judge a diamond''s cut with absolutely no sound scientific basis for it. When I visited their booth their own employee couldn''t even explain how to use it the way GIA intended. The result is a $1600 gadget and another bit of pseudo-science to add to the heap. Serious gemologists expect more from ''The World''s Foremost Authority.''

The reason so many people are walking away from the GIA approach to diamond grading and towards other approaches is because somewhere along the way the GIA chose to abandon science and adopt what I call the ''eehh...that''s close enough'' approach.

GIA''s founders were highly respected gemologists that put science first. Most people in the industry received their basic diamond and gemological training from the GIA and they look to the GIA for gemological leadership. But somewhere along the way the culture at the GIA changed. Laboratory leadership took a back seat to administrative interests. The GIA became Vatican-like in its ability to accumulate industry donations and the interests of science suffered as the influence of donors helped set the institutional agenda.

At their recent cut grade seminar presented at the JCK show, the GIA reps used a great deal of their time explaining why certain less-than-excellent characteristics were somehow still acceptable as ''excellent.'' Or as I put it, they spent a lot of time saying the equivalent of ''eehh...that''s close enough.'' It boggles the mind to think that GIA''s top gemologists think the most accurate approach to cut grading involves methodically taking all of the precise measurements of a diamond, then averaging them, then arbitrarily rounding the averages.

A product like the DD is merely a symptom of a larger organizational problem. And the DD deserves all of the criticism anyone wants to bother throwing at it.

Make no mistake, I and (I''m quite sure) others, are not anti-GIA. We are pro-gemology! By way of our early gemological education we are all associated with GIA. Some, like me, have even gone on to serve our local GIA Alumni chapters. It is only natural that we feel the need to be proud of our association with the GIA and we cannot hold our tongues when things are so obviously amiss.

Regards,

Bill Scherlag

Bill, thanks for your eloquence. This voices how many of us feel.

The energy being expended here could be more productively spent on larger issues than painting or DD.

 

[RockDoc]

A product like the DD is merely a symptom of a larger organizational problem. And the DD deserves all of the criticism anyone wants to bother throwing at it.


Cat says....... "Throw in some more litter - PLEASE!"


Seriously, I think Jonathon''s post talking about getting the stone out of store spotlights, so consumers can see another lighting environment or too, hits the nail on the head. It is DISPLAY TOOL not a gemological evaluation tool for cut.

I remember looking at the window spot lights that are "very blue" in the windows at 47th St. so perhaps it is better for consumers to see a stone in the DD environment than that, but I think the overwhelming opinion is that it is for display purposes.

Curiously, at the GIA exhibit booth at the AGS Conclave the DD was NOT on display. So I have not seen it in person.

The whole concept of using it to grade diamonds whether for color or cut, seems very skewed.

I am sort of curious as to why the viewing area is rectangular. One would think a circular dome like environment would have been more proper. Also adjustable angle views for tilt, and adjustable angle for distance from the lighting as well as a way to remove any UV would make a little more sense.

Rockdoc

 

[adamasgem]

Date: 6/13/2006 4:13:25 AM
Author: strmrdr
Garry your blowing it way out of proportion.
The DD isn''t the reason the things that we don''t like about the GIA system are there.
politics is....
frankly the DD talk is a red herring and you and a lot of others had your mind made up without ever having seen one or even pictures of diamonds under one and have been trying to shoot it down since.
Wrong target...... and its side tracking the work that the energy should be applied too.

Frankly all it is anymore is an ego fest with you an annoyance to many and a chance for Marty to say nasty things about people he hates.

think bout it :}
Now im going back to laying on couch holding my jaw.
night.

I guess you might want to be added to my "list", after a comment like that..
Holding your jaw Storm?, what did you do, finally extricate it from your backside??

 

[JohnQuixote]

As I catch up on my reading tonight I wanted to pass on clarifications:

First reactions here were strong because initial impressions were based on Report Check (which had some glitches when introduced) and earliest grading, which has since been fine-tuned.

The good news: Indications from GIA are that diamonds of the type commonly seen on PS would not receive a penalty for painting. At JCK, and again today, we discussed indexing details of several ACA New Line diamonds and another non-branded, painted superideal we had in-house. All were within GIA's tolerances for EX. Assuming we understand indexing averages the same way this is positive news. It agrees with our eyes and the eyes of our clients. We still disagree with methodology, but GIA has been helpful in explaining approach and is committed to enabling further understanding. More to come.

Meanwhile the GOG survey stone and porch stone both fall outside of EX. This might explain Rhino’s position.

Following up:

Date: 6/2/2006 4:13:40 PM
Author: Rhino

Hi John,

Thanks for the update. A few questions.

In your past comments I recall you using the term 'mass grading' ... ie. all (the mass) of painted girdle diamonds taking a hit. Clarify 'proprietary grading'. Are you referring to the the systematic degree of painting GIA does to determine which grade the painted stone will fall in? If so, I understand that.

You're welcome. Discussions ongoing. Proprietary grading just means predictive estimates done away from the lab, and by 'mass grading' I was referring to methodology; the use of one measuring stick (X degrees avg dev) to judge all diamonds (en masse).

From what I have learned studying this, the VG grade was determined because of what the observers reported in their observation testing. Since that testing is now complete perhaps the graders in the labs don't feel the necessity to do it again so it would make sense that they now judge painting or digging to determine the threshold that makes the VG grade.

I assume you're right since it's all done via Sarin; indexing analysis in particular.

Of the diamonds receiving the VG grade for brillianteering I have been able to note these differences as well. Admittedly however of the one stone I've seen that got the 'Good' grade I wasn't able to note any optical difference but only the degree of painting as noted from the girdle measurements and viewing it via the DiamCalc.

Well...I have to readjust my paradigms, since it takes more painting than we thought for GIA to bump down to VG.

Perhaps we can all bump the painting defcon back up a digit or two.

 

[Garry H (Cut Nut)]

Storm I am not anti GIA - I am a great fan of their colored stone treatment synthetic detection etc. They do great work for us all - trade and consumers.

As Bill said

Date: 6/13/2006 12:04:38 PM
Author: Capitol Bill
Storm,

You''re right. The DD is not the issue. The issue is that the GIA is offering the DD as a definitive way to judge a diamond''s cut with absolutely no sound scientific basis for it. When I visited their booth their own employee couldn''t even explain how to use it the way GIA intended. The result is a $1600 gadget and another bit of pseudo-science to add to the heap. Serious gemologists expect more from ''The World''s Foremost Authority.''

The reason so many people are walking away from the GIA approach to diamond grading and towards other approaches is because somewhere along the way the GIA chose to abandon science and adopt what I call the ''eehh...that''s close enough'' approach.

GIA''s founders were highly respected gemologists that put science first. Most people in the industry received their basic diamond and gemological training from the GIA and they look to the GIA for gemological leadership. But somewhere along the way the culture at the GIA changed. Laboratory leadership took a back seat to administrative interests. The GIA became Vatican-like in its ability to accumulate industry donations and the interests of science suffered as the influence of donors helped set the institutional agenda.

At their recent cut grade seminar presented at the JCK show, the GIA reps used a great deal of their time explaining why certain less-than-excellent characteristics were somehow still acceptable as ''excellent.'' Or as I put it, they spent a lot of time saying the equivalent of ''eehh...that''s close enough.'' It boggles the mind to think that GIA''s top gemologists think the most accurate approach to cut grading involves methodically taking all of the precise measurements of a diamond, then averaging them, then arbitrarily rounding the averages.

A product like the DD is merely a symptom of a larger organizational problem. And the DD deserves all of the criticism anyone wants to bother throwing at it.

Make no mistake, I and (I''m quite sure) others, are not anti-GIA. We are pro-gemology! By way of our early gemological education we are all associated with GIA. Some, like me, have even gone on to serve our local GIA Alumni chapters. It is only natural that we feel the need to be proud of our association with the GIA and we cannot hold our tongues when things are so obviously amiss.

Regards,

Bill Scherlag

Tahnks Mate, and have a great trip Bill.

I am very pro good cut grading and i have not seen much of it from GIA Storm - not for the last 8 years since they first began publishing their findings. And what is wrong with the scientific peer review process anyway? I play the ball, not the man. And in this case they designed a cut grade system based on a dealers twin fluoro lamp. And that is dumb and needs to be discredited publicly.

 

[strmrdr]

Garry, nothing wrong with peer review the problem is how its being handled, jumping the gun, unscientific responses, and immature behaviour.
Name calling and insults dont get anything done.
My comment was that the DD threads were a waste of time and energy while it looks like John and Brian who after the first round of griping have been doing what should have been done.
Talking to GIA and getting the scientific ducks in a row.
There are many more area that that needs to be done with that are far more important than a display light box.
My comment was that it turned into an ego fest on here that is getting nowhere.

John, glad to see its being worked on much better than the hype that had been happening earlier.

Marty, I still see it that way, you don''t like GIA and I think a lot of your comments are colored by that. Others have mentioned the same thing.
I apologize if my comment upset you in any way.

 

[adamasgem]

Date: 6/14/2006 9:35:47 AM
Author: strmrdr
Marty, I still see it that way, you don't like GIA and I think a lot of your comments are colored by that. Others have mentioned the same thing.
I apologize if my comment upset you in any way.

Apology accepted.

Storm, I don't "hate" GIA, I dispise what their management has done to their employees and the industry, and I'll work in public to expose and hopefully help correct, major screwups they have made. Maybe the "foremost authority" will get their act together now that top management has been starting to be shaken up, due largely in part, to their arrogance.

There are many fine people there, and unfortunately many who have left, and they greatly contribute to the understanding of what technologically induced problems have been occuring in the trade. Unfortunately, they still suffer from the not invented here syndrome, the inability to admit mistakes, and a general pandering to the global trade. They are too money motivated.

Not the attributes of a supposedly "educational" institution. Their actions have been more Enron or WorldCom like.

 

[Garry H (Cut Nut)]

Date: 6/14/2006 9:35:47 AM
Author: strmrdr
Garry, nothing wrong with peer review the problem is how its being handled, jumping the gun, unscientific responses, and immature behaviour. When and which thread did I jump the gun in Storm? i have given GIa the benefit of doubt and rather gradually worked at why they came up with a system that favours slightly deeper proportions and penalizes shallower sets.
Name calling and insults dont get anything done. ????? What insults?????
My comment was that the DD threads were a waste of time and energy while it looks like John and Brian who after the first round of griping have been doing what should have been done.
Talking to GIA and getting the scientific ducks in a row.
There are many more area that that needs to be done with that are far more important than a display light box.
My comment was that it turned into an ego fest on here that is getting nowhere.I think the analogy is somewhat different - John is working on a part of the system they recognized as wrong. I am working on a part of the system that they think is right - and this is the best way and the best place to catch their attention - you think the GIA Cut Study team, lab people and others in GIA do not read this site?

John, glad to see its being worked on much better than the hype that had been happening earlier.

Marty, I still see it that way, you don''t like GIA and I think a lot of your comments are colored by that. Others have mentioned the same thing.
I apologize if my comment upset you in any way.

Simply put, GIA devised a cut grading system based on dealer lighting.
Dealers do not use dealer lighting for cut grading.

 

[strmrdr]

Garry,
The thread comparing the DD to the other device before you had seen the DD or images under the DD == jumping the gun.

calling it dealer lighting is not scientific - dealer lighting is non-defused color corrected fluorescent tubes. - that isn''t what is used.

Now if you want to call it a diamond dealers grading system and discuss how too much of the observation study was done with dealers then your on more solid ground.

As for insults there have been plenty thrown out.

I know the GIA cut team reads this site as does the AGS team.
......

Reading these threads one would get the impression that the evil DD is responsible for all that''s wrong with the GIA cut grade and that is not correct.

 

[Rhino]

Sorry for not responding here as I''d have liked but have some commentary.

Date: 6/13/2006 2:53:04 AM
Author: Garry H (Cut Nut)
I may have used a slightly higher angle storm - I never had the information from GIA at the time - but you can see from the center of the stones that it was not anywhere near as high as Rhino''s.

Are you getting the message now though?

GIA modeled dealer lighting.
Dealers do not use color and clarity lighting to grade the cut / appearance of diamonds.

It seems starnge to me that the major ''authority'' in diamond grading made a big bo-bo and no one really seems to care around here?

Garry ... I care. Perhaps more than you realize. Regarding the angles of observation, I am not finding any notable difference in the observations just as I don''t when I bring the stones outside into natural diffused daylight.

GIA didn''t model dealer lighting. There are observations similar to it but it would not be accurate to say that that was their goal. Typical dealer lighting is non diffused fluorescent tubes and of a different temperature than what GIA is using in the DD. I have video taped the differences between typical dealer lighting and diamonddock lighting as reported in this thread. In the dealer lighting I even recorded the differences in appearance between using various backdrops.

Regards,

 

[belle]

insider gemologist

"However, the DiamondDock™ is not a requirement for discerning differences in diamond appearance. Most diffused light environments that have white-colored ceilings and walls can be used with almost the same results. A standard color-grading box like the Macbeth Judge II, or a common fluorescent desk lamp with D65 fluorescent tubes used in a neutral environment, is a useful alternative for assessing brightness and pattern."

 

[Rhino]

Date: 6/16/2006 10:44:10 PM
Author: belle


insider gemologist

'However, the DiamondDock™ is not a requirement for discerning differences in diamond appearance. Most diffused light environments that have white-colored ceilings and walls can be used with almost the same results. A standard color-grading box like the Macbeth Judge II, or a common fluorescent desk lamp with D65 fluorescent tubes used in a neutral environment, is a useful alternative for assessing brightness and pattern.'

Thanks for posting this belle. I just caught it in the newletter this morning too. Not sure if you caught our video on the subject but other useful alternatives we demosntrate in that are ...

1. Outside on a cloudy day (most natural source of diffused daylight).
2. Outside on a sunny day (must be in the shade though for examination of brightness).
3. The diffuse daylight attachment at the end of microscopes.
4. As the GIA article points out, dealer desklamp lighing it useful as well but encourages a neautral backdrop instead of examing with tweezers and/or bright backdrop. We show the difference in appearance with both in the video.

There may have been one or 2 more views that I can't think of off the top of my head but my personal favorite alternative is outside on a cloudy day. Of course this is not practical for jewelry stores since we are not covered by insurance if we bring diamonds outside so indoors, if one isn't going to make the investment is a good suggestion/alternative. I would just emphasize the use of a neutral backdrop instead of a bright one. My most current project is demonstrating the differences in appearnace from GIA Ex to GIA VG's in both environments (ouside cloudy day and DD) to show the layman the corellations. In it we're using 4 varieties of GIA VG's which each get the VG grade for different reasons.

Regards,

 

[Garry H (Cut Nut)]

Date: 6/16/2006 2:28:27 PM
Author: Rhino
Sorry for not responding here as I''d have liked but have some commentary.

Date: 6/13/2006 2:53:04 AM
Author: Garry H (Cut Nut)
I may have used a slightly higher angle storm - I never had the information from GIA at the time - but you can see from the center of the stones that it was not anywhere near as high as Rhino''s.

Are you getting the message now though?

GIA modeled dealer lighting.
Dealers do not use color and clarity lighting to grade the cut / appearance of diamonds.

It seems starnge to me that the major ''authority'' in diamond grading made a big bo-bo and no one really seems to care around here?

Garry ... I care. Perhaps more than you realize. Regarding the angles of observation, I am not finding any notable difference in the observations just as I don''t when I bring the stones outside into natural diffused daylight.

GIA didn''t model dealer lighting. There are observations similar to it but it would not be accurate to say that that was their goal. Typical dealer lighting is non diffused fluorescent tubes and of a different temperature than what GIA is using in the DD. I have video taped the differences between typical dealer lighting and diamonddock lighting as reported in this thread. In the dealer lighting I even recorded the differences in appearance between using various backdrops.

Regards,

Rhino you still have not shown anything is wrong with my modelling of Diamond dock lighting from the 45 degree observer angle. It is quite obvious that if you change the direction of lighti shining on a diamond - you will get a different appearance.

As Belle has shown - DD was modelled on Dealer lighting - they have made it very clear in the foundation article.
From http://www.gia.edu/newsroom/issue/2798/2564/insider_newsletter_details.cfm#4
A standard color-grading box like the Macbeth Judge II, or a common fluorescent desk lamp with D65 fluorescent tubes used in a neutral environment, is a useful alternative for assessing brightness and pattern.

From http://www.gia.edu/pdfs/cut_fall2004.pdf

The same diamond can look quite different depending on the type and position of lighting that is used (figure 3). On the one hand, for cutting diamonds and for evaluating brightness and the quality of diamond cutting in general, most manufacturers use overhead fluorescent lights and/or desk lamps with daylight-equivalent fluorescent bulbs; dealers and brokers generally use similar desk lamps in their offices (figure 4). However, this type of diffuse lighting suppresses the appearance of fire (again, see figure 3). On the other hand, retail environments generally provide spot, or point source, lighting (usually with some overall diffuse lighting as well), which accentuates fire (figure 5).

Therefore, when we wanted solely to study the effects of brightness, we used dealer-equivalent lighting, which consisted of daylight-equivalent fluorescent lights mounted in fairly deep, neutral gray viewing boxes…

Figure 4. Diamond manufacturers and dealers typically
view and assess diamond appearance and cut quality
in offices with fluorescent desk lamps. Objects in the
room, including the observer, can block or affect light
shining on the crown of a polished diamond.
Photo by A. Gilbertson. (this picture shows a man using a desk light in a similar way to the DD in the current GIA newsletter- I have posted it before - it is available on the link above).
I do not believe manufacturers, dealers and cutters use desk lamps “for evaluating brightness and the quality of diamond cutting”. Yes they do and should use overhead fluorescent lights, but not desk lamps - ask for yourselves - I have asked many and watched many. And even if some people in the trade do use the same lights they use for color and clarity grading for cut grading, this does not make it correct, and it certainly should not have become the basis of a grading system for brightness and pattern.

Storm I am not bashing GIA. I am bashing the science they used to devise their grading system because it is flawed.

Rhino are you really up to the challenge to take some photo''s from the correct angles with some normal stones and post and email me their diamcalc files so we can reaally make the best possible DiamCalc lighting to model DD if you really believe my model is wrong? That does not need to be a challenge to prove their system is good or bad, right or wrong. Just a challenge to follow careful procedures and document it all. (BTW all I do have notes of the angles and viewing positions from my original tests some months ago - granted the video''s may have been from the wrong angle Storm- but they were not actually ever going to be part of what I was ''documenting''. They were initial experiments for my own purposes.)