Yellow in an Aset?

[iota15]

http://www.goodoldgold.com/diamond/7801/

Take a look at Aset of this O colored August Vintage Cushion. What does the yellow in the Aset represent? The culet looks white, so white = leakage.

Does the yellow also represent leakage, but is colored by the O color of this stone?

 

[tyty333]

I'm thinking it would normally be white and would be light loss? Very unusual looking pic though!

So, yes to basically what you said.

 

[iota15]

I agree - let me post it here for reference:

 

[Cehrabehra]

No... no, that stone has very little leakage.... Dunno why it looks like that, but I wouldn't worry about that aset. It almost looks like someone experimented with their aset and divided what is normally the green area up into two zones. Who knows. But on the diamx you can see leakage too, what there is of it.

 

[antelope1]

But there is yellow in the DiamXray too...isn't that strange?

 

[ChunkyCushionLover]

I agree - let me post it here for reference:

Iota15,

White = leakage ONLY for a colorless diamond with a backlit white background.

Leakage areas in this stone are tinted yellow because this diamond (an O color) absorbs blue wavelengths turning white light into yellow.
The yellow color is the strongest in areas which exit the crown after the longest light path through the diamond. The light path through the culet and out through the crown is very short so this region looks the least yellow.

Further, GOG enhances the saturation of colors in their ASET to highlight the contrast between colors, so the yellow is even more vibrant than if seen through a regular handheld ASET.

I see small regions of leakage in this stone and they match in both Diamxray and ASET, but they are minnimal and nothing to worry about.
The resolving contrast differences between areas of the crown that leak versus are lit by low angle sources is better resolved in the ASET image.

CCL

 

[iota15]

Okay.. so yellow = leakage because of 1) the color saturation enhancement made by GOG; and 2) the fact those yellow areas are actually leaking light.

Why does there appear to be more leakage in the Aset than in the Diamxray (IS)?

 

[ChunkyCushionLover]

2) the fact those yellow areas are actually leaking light.
The areas that don't reflect light off the colored plastic in ASET will appear yellow if the white light travels long enough through the diamondWhy does there appear to be more leakage in the Aset than in the Diamxray (IS)?

In Idealscope (Diamxray is better but still has the same problem) the resolution isn't as good in the Leakage/Low Angle areas may be blurred and show light red/pink instead of showing contrast between the green/white areas in the ASET.

Perhaps Garry or Rhino can comment on where the cutoff is for leakage/low angle light in Idealscope and DiamXray.

 

[iota15]

So let me check if I understand correctly - due to resolution quality or the nature of the tool itself, the Diamxray or IS will show areas of red/pink where there should be white or green? This is a rather serious flaw, isn't it?

In the case of this particular diamond, the blurred (increased) red areas cover portions of the stone that are leaking (white, or in this case, yellow).

 

[Amys Bling]

because the diamond is an O color- and therefore yellow in tint, the leakage in the aset will be yellow as opposed to white? Curious as to what an aset image of fancy colored stones would look like!

 

[stone-cold11]

Curious as to what an aset image of fancy colored stones would look like!

A mess. Difficult to decipher.

 

[Amys Bling]

Curious as to what an aset image of fancy colored stones would look like!

A mess. Difficult to decipher.

I can only image an aset for a green diamond- would the light return and leakage be green? haha

 

[yssie]

So let me check if I understand correctly - due to resolution quality or the nature of the tool itself, the Diamxray or IS will show areas of red/pink where there should be white or green? This is a rather serious flaw, isn't it?

In the case of this particular diamond, the blurred (increased) red areas cover portions of the stone that are leaking (white, or in this case, yellow).

IMO it is a serious flaw in the use of a single IS/DiamX/ASET image to try to determine the overall multi-environment performance of a stone, not of the tools in question.

I don't see the issue with this pair of images though. The green in the ASET is supposed to be red in the DiamX, and in this ASET it is in places difficult to distinguish between yellow and green due to the colour saturation enhancements. If a virtual facet is on the cusp of the blue/red (black/red in IS) angular boundary, the slightest tilt when the stone was imaged will change the apparent colour - and we don't have this information because GOG probably does not use a level calibrated to tenths and possibly hundreths of a degree when placing each stone into the desktop device, because we don't know what accuracy the colour divisions are manufactured to on the devices in question (perhaps Jon/Garry will chime in as CCL requested earlier) and because even if they did it wouldn't make any apparent real-world difference whatsoever.

ETA: makes sense that the 'leakage' appears almost white through the open culet and yellower as we radiate outward - longer ray paths through the stone allow more opportunity for blue-wavelength absorption

 

[iota15]

I understand the restrictions of a single image Aset, but even within the single image, white areas show up as red due to blurring? Isn't this quite misleading?

There's also significantly more leakage (yellow) in the Aset than there is leakage in the Diamxray image. I note the culet and the kozibe effect of the culet match up in both images, so I don't believe there is any significant tilt difference between the Aset and Diamxray. So why is there so much more leakage (relatively speaking of course) in the Aset than in the DX?

 

[ChunkyCushionLover]

because the diamond is an O color- and therefore yellow in tint, the leakage in the aset will be yellow as opposed to white? Curious as to what an aset image of fancy colored stones would look like!

Similarly to a colorless except add its color and saturation of the color to the ASET image everywhere.

 

[yssie]

I understand the restrictions of a single image Aset, but even within the single image, white areas show up as red due to blurring? Isn't this quite misleading?

There's also significantly more leakage (yellow) in the Aset than there is leakage in the Diamxray image. I note the culet and the kozibe effect of the culet match up in both images, so I don't believe there is any significant tilt difference between the Aset and Diamxray. So why is there so much more leakage (relatively speaking of course) in the Aset than in the DX?

where? I don't see it - in fact, as you say, they correlate astoundingly well. For obstruction/red it would take a few tenths of a degree difference, which is impossible determine by looking at the photos.

ETA - also to keep in mind - software like photoshop is enhancing saturation by choosing some hue (and I assume not by gaussian!) and decreasing the 'mixing region' on either side, so the 'blur' that is the bound between yellow/red or yellow/green is reduced (and depending on what cutoff(s) the programme chooses, if closer to red or green, the apparent area of 'yellow' increases...)

 

[ChunkyCushionLover]

I understand the restrictions of a single image Aset, but even within the single image, white areas show up as red due to blurring? Isn't this quite misleading?

There's also significantly more leakage (yellow) in the Aset than there is leakage in the Diamxray image. I note the culet and the kozibe effect of the culet match up in both images, so I don't believe there is any significant tilt difference between the Aset and Diamxray. So why is there so much more leakage (relatively speaking of course) in the Aset than in the DX?

I'm just not seeing what you are.

The red overpowers the yellow in areas where its a mix of low angle illumination and leakage in the Diamxray. (Perhaps the image is overexposed a but but its minor).

The light green doesn't overpower the yellow quite as much in ASET so its seen more clearly.

No tilt between the images.
YMMV it depends on your monitor colors as well.

No its not a flaw once one realizes that those areas are lit by mid/low angle light and also have leakage adjacent almost in the same region. The Diamxray isn't showing red its showing pink in most of those areas consistant with leakage/low angle illuminastion.

Refelctor images of light yellow and some fancy yellow diamonds is still relatively easy to interpret just remember to expect various saturations of yellow added to the other colors.

 

[Garry H (Cut Nut)]

Perhaps Rhino will send me the 3D Gem file and I can settle this (since he knows i can model his exact proportions anyway )
But here is a quick and dirty with a color that would not quite be 'O' modeled in DiamCalc.

 

[Garry H (Cut Nut)]

OOps - double post - the areas of leakage in stones like this are often multiple bounces - eventually leaving via the pavilion and as such they will be by definition areas with more exaggerated yellow. Infact this rough could probably have made a fancy yellow if it was made into a readiant or crushed ice cushion.

 

[Amys Bling]

Thanks for explaination and pics Gary. So, does the radiant/crushed ice cushion cut allow for more bounces of light therefore exaggerating the color?

 

[Garry H (Cut Nut)]

I understand the restrictions of a single image Aset, but even within the single image, white areas show up as red due to blurring? Isn't this quite misleading?

There's also significantly more leakage (yellow) in the Aset than there is leakage in the Diamxray image. I note the culet and the kozibe effect of the culet match up in both images, so I don't believe there is any significant tilt difference between the Aset and Diamxray. So why is there so much more leakage (relatively speaking of course) in the Aset than in the DX?

It would be nice in a perfect world if everyone used the exact same reflector image, but as JulianWikiLeaks points out, it is far from a perecft world!
It would appear the colours in all Rhino's reflectors are saturation of contrast enhanced a bit - especially the ASET (but much less than many others).

 

[Garry H (Cut Nut)]

Thanks for explaination and pics Gary. So, does the radiant/crushed ice cushion cut allow for more bounces of light therefore exaggerating the color?

oui (yes)
There are several long discussions https://www.pricescope.com/community/threads/discussion-of-aset-in-simple-terms.150589/ this being the most recent Amy

 

[iota15]

OOps - double post - the areas of leakage in stones like this are often multiple bounces - eventually leaving via the pavilion and as such they will be by definition areas with more exaggerated yellow. Infact this rough could probably have made a fancy yellow if it was made into a readiant or crushed ice cushion.

In the Aset, there are yellow colors at the 12 o'clock, 3, 6 and 9. Why are these areas of leakage not represented in the IS image?

 

[Garry H (Cut Nut)]

OOps - double post - the areas of leakage in stones like this are often multiple bounces - eventually leaving via the pavilion and as such they will be by definition areas with more exaggerated yellow. Infact this rough could probably have made a fancy yellow if it was made into a readiant or crushed ice cushion.

In the Aset, there are yellow colors at the 12 o'clock, 3, 6 and 9. Why are these areas of leakage not represented in the IS image?

I do not see a difference that you can not get to match the other by blowing out one or the other with simply contrast or brightness Iota

 

[ChunkyCushionLover]

OOps - double post - the areas of leakage in stones like this are often multiple bounces - eventually leaving via the pavilion and as such they will be by definition areas with more exaggerated yellow. Infact this rough could probably have made a fancy yellow if it was made into a readiant or crushed ice cushion.

Something is wrong with the resolution of the generated idealscope in your cushion. Colors are blurred together especially the red pink which has IMO too much red, attach the .gem I will fix it and repost.

 

[iota15]

Are the areas I circled on the Aset leakage or not?

 

[Garry H (Cut Nut)]

Are the areas I circled on the Aset leakage or not?

Iota it is exactly the same as anASEt image center of a diamond with a 40.75 degree pavilion - there is mixing of red and green = yellow.
If I change the ASET setting to red going down to 46 or 47 degrees the yellow turns red.
If I bring the green up and the red back to 44 degrees the yellow turns green.
Interesting huh?

 

[ChunkyCushionLover]

Are the areas I circled on the Aset leakage or not?

Iota it is exactly the same as anASEt image center of a diamond with a 40.75 degree pavilion - there is mixing of red and green = yellow.

Gary by definition in ASET one should not get mixing of Red and Green in the same area. That certainly is not the case for any AVC I have ever seen. Green/White or Green/Yellow in this case okay but Red/Green ????.

Iota's point is supported by the following, for this AVC (I've added a light yellow natural diamond absorption to it) the correlation between the IS and ASET is much better.

 

[ChunkyCushionLover]

Also isn't it highly unlikely that one could observe such a high amount of red from dispersion viewed through an ASET scope?
Red(dispersion) + Green = Yellow

 

[Garry H (Cut Nut)]

Here is what I modelled and put on Youtube:
http://www.youtube.com/watch?v=Z0xAfLHsWIs

ASET colour changes with only a small pavilion variation modelled in DiamCalc with a mid point of 40.74 pavilion. At this exact point the center of the stone recieves light from the ASET Red Green edge and the shallower angle draws from green and the deeper from the red zone. Mixing in the middle creates yellow.

After looking at a few stones and gently tilting, I can see how photo shop will 'adjuts' these colors to Yellowish.
PS - I doubt there would be much dispersion happening in that video