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virtual facet article help.

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strmrdr

Super_Ideal_Rock
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Rather than send this by email to a few people I decided to post it here.
I reserve the right to make the final decision but would like some input.

I am having a dilemma with my virtual facet article.
When referring to virtual facet size should I call them large/med/small based on absolute size or relative size to equal sized diamonds?

Absolute size makes more sense in relation to scintillation event size but is much harder to explain and more confusing.
By the sounds of is AGS is using absolute size in reference to scintillation events.

Relative size of virtual facets to similar sized diamonds is more in line with what consumers will actually see, as I will not be separating flashes into fire and white light. (Which is where AGS is saying it matters)

I will be discussing flash size and touch on scintillation events in my article but contrast patterns formed by virtual facets will be the main topic.

Here is a sample of how I will be using it:
The small to med virtual facets under the crown step facets provide smaller and more frequent flashes in direct light, where the large center virtual facets provide larger and less frequent flashes.
In low light the large virtual facets will produce most of the flash.
 
Storm i think you need to base it on the smallest that can be seen (a function of size and brightness / contrast) and the largest commonly seen.
Place medium in between - but you should seek to define it firstly
 
Storm


I was leaning toward relative as I think that would be easier for consumers to understand. For example, in a RB the arrows would always be the large virtual facets regardless the size of the diamond.
 
not easy to see in a .01ct
It needs to be an absolute size, not relative
 
Date: 8/10/2008 2:15:43 AM
Author: Garry H (Cut Nut)
not easy to see in a .01ct
It needs to be an absolute size, not relative

Agreed, but then how do you differentiate the relative different size virtual facets in the .01ct?
 
I should have actually said how do you differentiate the different size virtual facets in the .01ct?
 
AGC you differentiate by size in millimeters or microns.
Size is THE issue - what ever method that considers virtual facets ought consider if you can see it.
So any VF rules must also be diamond size related.

A 0.50ct asscher probably will not show patterns that make an asscher desirable.
Above 5ct you need 4 steps not 3 steps to ''add value''

Princess cuts under 1/2ct have VF''s too smal to enjoy
 
Date: 8/10/2008 5:38:56 AM
Author: Garry H (Cut Nut)
AGC you differentiate by size in millimeters or microns.
Too complicated for the target audience.

I''m tempted to use the 6mm DC default tolk at 6mm x 6mm with a 500pixel x 500 pixel window as the reference if I use absolute.
 
You might take a look at the February 1 issue of Rapaport which had a nice consumer-level article about virtual facets and scintillation which I think was an overview of the AGSL research. Apparently they're dividing this up into 4 sizes (add extra-small), with cool color-coded maps. No indication there whether the sizes are absolute or relative. Maybe some irony of this trade magazine publishing a "pricescope consumer"-level cover story
2.gif
. But I think it may be along the lines of what you're trying to put together.
 
Date: 8/10/2008 6:31:59 AM
Author: strmrdr

Date: 8/10/2008 5:38:56 AM
Author: Garry H (Cut Nut)
AGC you differentiate by size in millimeters or microns.
Too complicated for the target audience.

I''m tempted to use the 6mm DC default tolk at 6mm x 6mm with a 500pixel x 500 pixel window as the reference if I use absolute.
Me thinks you underestimate the intellect of the "audience" Storm.

Also 6mm is small in the world of diamonds where this stuff counts for a lot.
1ct should be a minimum standard.

Go search for 1 arc minute - that is the generally accepted standard for 20:20 vision between black and white objects.

Then calculate the size of virtual facet that can be seen when there is good contrast. You will also need to standardise the viewing distance - 8 inches for AGS, 35cm, 40cm to 45cm for most others in this field.
You would probably need to research Field and others (as Sergey has) to understand the relationship between contrast and acuity.

It really is the starting point on virtual facets
 
Date: 8/10/2008 12:16:00 AM
Author:strmrdr
Rather than send this by email to a few people I decided to post it here.
I reserve the right to make the final decision but would like some input.

I am having a dilemma with my virtual facet article.
When referring to virtual facet size should I call them large/med/small based on absolute size or relative size to equal sized diamonds?

Absolute size makes more sense in relation to scintillation event size but is much harder to explain and more confusing.
By the sounds of is AGS is using absolute size in reference to scintillation events.

Relative size of virtual facets to similar sized diamonds is more in line with what consumers will actually see, as I will not be separating flashes into fire and white light. (Which is where AGS is saying it matters)

I will be discussing flash size and touch on scintillation events in my article but contrast patterns formed by virtual facets will be the main topic.

Here is a sample of how I will be using it:
The small to med virtual facets under the crown step facets provide smaller and more frequent flashes in direct light, where the large center virtual facets provide larger and less frequent flashes.
In low light the large virtual facets will produce most of the flash.
Sounds clear and understandable....
 
Date: 8/10/2008 5:38:56 AM
Author: Garry H (Cut Nut)
AGC you differentiate by size in millimeters or microns.
Size is THE issue - what ever method that considers virtual facets ought consider if you can see it.
So any VF rules must also be diamond size related.

A 0.50ct asscher probably will not show patterns that make an asscher desirable.
Above 5ct you need 4 steps not 3 steps to ''add value''

Princess cuts under 1/2ct have VF''s too smal to enjoy
Why would you say that Garry..., I dont think you will "need" a four step to add value to any size Asscher Cut...

The problem with "most" 4 step pav. that I witnessed is that P1 is usually the largest of the four and not for beauty reasons....
27.gif


I have seen plenty of 10 carats ++ Asschers with 3 pav steps..., and if cut correctly..., they will look better than any 4 pav (in my opinion)..., it will greatly depend on the table size, crown height and angles relative to the whole pavilion structure.
 
Date: 8/10/2008 8:23:05 AM
Author: DiaGem

Date: 8/10/2008 5:38:56 AM
Author: Garry H (Cut Nut)
AGC you differentiate by size in millimeters or microns.
Size is THE issue - what ever method that considers virtual facets ought consider if you can see it.
So any VF rules must also be diamond size related.

A 0.50ct asscher probably will not show patterns that make an asscher desirable.
Above 5ct you need 4 steps not 3 steps to ''add value''

Princess cuts under 1/2ct have VF''s too smal to enjoy
Why would you say that Garry..., I dont think you will ''need'' a four step to add value to any size Asscher Cut...

The problem with ''most'' 4 step pav. that I witnessed is that P1 is usually the largest of the four and not for beauty reasons....
27.gif


I have seen plenty of 10 carats ++ Asschers with 3 pav steps..., and if cut correctly..., they will look better than any 4 pav (in my opinion)..., it will greatly depend on the table size, crown height and angles relative to the whole pavilion structure.
I guess it is all in the virtual facets DG
emwink.gif
 
Garry

I understand what you are saying. Storm, don''t give up on us yet....It is not too complicated to discuss here and is actually quite intellectually stimulating.

I was originally wanting to go with absolute but felt it would be more confusing. I am still not sure how to clearly explain some things with absolute such as small diamonds that will have all small virtual facets with some not being visible, some marginally being visible and then the primary visually contributing small virtual facets that are being seen.....then really confuse things with the tilt angles.


I am just thinking out loud.
 
Date: 8/10/2008 8:34:03 AM
Author: Garry H (Cut Nut)

Date: 8/10/2008 8:23:05 AM
Author: DiaGem


Date: 8/10/2008 5:38:56 AM
Author: Garry H (Cut Nut)
AGC you differentiate by size in millimeters or microns.
Size is THE issue - what ever method that considers virtual facets ought consider if you can see it.
So any VF rules must also be diamond size related.

A 0.50ct asscher probably will not show patterns that make an asscher desirable.
Above 5ct you need 4 steps not 3 steps to ''add value''

Princess cuts under 1/2ct have VF''s too smal to enjoy
Why would you say that Garry..., I dont think you will ''need'' a four step to add value to any size Asscher Cut...

The problem with ''most'' 4 step pav. that I witnessed is that P1 is usually the largest of the four and not for beauty reasons....
27.gif


I have seen plenty of 10 carats ++ Asschers with 3 pav steps..., and if cut correctly..., they will look better than any 4 pav (in my opinion)..., it will greatly depend on the table size, crown height and angles relative to the whole pavilion structure.
I guess it is all in the virtual facets DG
emwink.gif
So you do agree
31.gif
 
Date: 8/10/2008 8:36:23 AM
Author: agc
Garry


I understand what you are saying. Storm, don''t give up on us yet....It is not too complicated to discuss here and is actually quite intellectually stimulating.


I was originally wanting to go with absolute but felt it would be more confusing. I am still not sure how to clearly explain some things with absolute such as small diamonds that will have all small virtual facets with some not being visible, some marginally being visible and then the primary visually contributing small virtual facets that are being seen.....then really confuse things with the tilt angles.



I am just thinking out loud.

Your among those that would get it if I went full out technical on it.
I don''t want to write it at a level that maybe 50 people who are into this type of thing will understand.
I want to write it so someone who just found PS 2 days ago and is buying their first diamond will understand.
 
Thanks risingsun and agc.

I''m trying to make the rest of it that easy to understand.
 
I decided to keep it simple for this article and maybe at a a latter date go into it more in depth.
By doing so I found I can avoid the issue I was having until I do more research and find an easy way to explain it.
Since I couldn''t sleep because of a toothache, the new article is about 95% done and almost ready for editing.

Thank you everyone for the help and opinions.
 
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