Light leakage, how can you tell in real life?

[teobdl]

The simulated lighting environment is not similar to most real life lighting.

I'm curious: what is expected to be drawn from that survey?

 

[Serg]

The simulated lighting environment is not similar to most real life lighting.

Why do you think so? I see similar diamond appearance on my kitchen.

I'm curious: what is expected to be drawn from that survey?



1) to check Possibility to rank different diamonds by pairwise comparison. Very often consumer needs select from many options, without special instruments it is very difficult mission for him.
2) see how different result is between trade and consumers.
Always sales person select cuts which he sells. Newbie selection is far away from trade preferences.
3) To check our metrics. offline tests with real diamonds are much more expensive and have less consistency.
we cut diamonds in Surat and need receive response from worldwide experts .
4) there are many other benefits from such survey

 

[Serg]

Bryan,

I have some toy for you.

Please pass below voting

http://expo.diamsort.dev.cutwise.com/qr/20

instead number 20 in the end of the link please use any other number between 20 and 100.( if many persons will use same link result may be any)

please publish which diamond was second and which diamond was third in your trial .

Thanks Serg,
I will try it. I need to get some 3D glasses first!

it was link to mono version.
below link for stereo movies( same diamonds). all movies are for real diamonds in same light conditions

http://ts.cutwise.com/demos/79/6f100c5c33b513bdf4e15c21aed0d0c5/sort/try/53d17da3d9500/stereo/

I advice You to pass mono version firstly

Question: When it says "like better" does that mean overall look or just which has more fire?

question would be any.
but usually we ask about "Overall look=what do you prefer ,.."

I suppose it is a lighting environment that heavily favors the observation of fire (to the detriment of brightness).
Yes, this light is good for Fire. But I disagree that this light kill the brightness.
I have opinion what most light environment had been used to take diamond photos( for online sales ) are:
1) Kill Fire
2) Overexposure Diamond, exaggerate Brightness
3) use too may big light sources

Light environment standardisation is very complex issue. we may model "Any light" but if we do a choice then at least 50% trade will disagree with our choice.



So my preferences might be quite different in a more normal (balanced) light environment. Anyway here is my vote for 2nd and 3rd, based on which had the most overall appeal to me. Admittedly I am a little biased towards rounds and princess.

it is reason why you sell it for many years and because you sale it for many years you are more and more biased
for round and princess.

If I had been voting just on fire, my rankings would have been different.

last years trade sale mainly Brightness . may be time to think about Fire too?

Rank: 2
Name: MSSPRINCESS
Fire Integral Score: 1.64

Rank: 3
Name: MSSC04
Fire Integral Score: 2.93

 

[Garry H (Cut Nut)]

Pretty amazing stuff. These experiments are great. Having watched the videos first and ranked them first, I agree that those graphs (at least in terms of order) correspond to what my eyes saw.

Also, I noticed the tolk was the brightest diamond to my eyes. What does your program say?

we have not yet Subjective Brightness metrics based on Stereo movies.
Old DC LightReturn Stereo metric gives 0.98 ( Total), 0.94( Table only)
it is typical what you need increase Fire you have to reduce Brilliancy ( if Brilliancy was high as in Tolkowsky round)

I have not had time these past few days to look at some diamonds and experiment with ways to make them "normally" dirty. I believe when we can find a way to do that
But as you say Sergey, and Teobld noted, the 40.7 is brighter and brightness has always been the enemy of fire and colored flashes.
I remain stubborn and unconvinced.

 

[Karl_K]

brightness has always been the enemy of fire and colored flashes.
I remain stubborn and unconvinced.

When it comes to an RB I am leaning to believe you are right it is impossible within the confines of the cut to have both the highest brightness and the highest fire in one diamond.
But I am not convinced it is a universal truth that applies to all possible faceting combinations.

 

[Serg]

brightness has always been the enemy of fire and colored flashes.
I remain stubborn and unconvinced.

When it comes to an RB I am leaning to believe you are right it is impossible within the confines of the cut to have both the highest brightness and the highest fire in one diamond.
But I am not convinced it is a universal truth that applies to all possible faceting combinations.

any cut can be consider as set of prism's.
for single prism you have to choice between Brightness and Fire.
To increase Fire you have to increase dispersion angle. Increasing dispersion angle( ETAS spot) increase astigmatism that reduce brightness of redirected light source( brightness of image light source on retina) .
Cut design can not break this Physical limitation .
Of course it is not block possibility to create cut which has more Brightness and Fire than Round cut with same size.

 

[Garry H (Cut Nut)]

It is interesting that many in the trade rarely see fire in diamonds in their day to day working life. I have taken diamonds into dealers toilets to check them for fire because it has been the only place there have been spot lighting.
Our friend David would be a point in case I think, and although he has never shared any info about the lighting it seems from looking at his photo's that the main source of color flashes is the light from his hands and the light entering the pavilion. Many old cuts have little and they should have some big bold flashes.

Bryan if you check with princess cut i think you will find stones under about 3/4ct (with 4 chevrons) have very little fire - its only once you get to say +2ct princess that you can see much fire.
Bryan here is a link to the MSS Princess cut in the videos http://www.octonus.com/oct/mss/diamPr0.html I think you would be happy to have that as a WF ACA.
Sergey can you share the chart that shows fire and frequency -I think you used it in an HRD presentation?

Regarding the lighting environment - it has been carefully considered. It possibly creates more fire than usual because of the strips of lighting and orientation - but by doing so we are able to increase the number of flashes and that means the higher counts are the same for the Tolkowsky standard and any stones being compared. So it is not an unfair setup. The only thing I would add is that by playing the video's on a large screen you will see fire that you would not see in person - but Sergey's brilliant OctoNus team are able to model the sizes of flashes that should be ignored.

 

[Serg]

It is interesting that many in the trade rarely see fire in diamonds in their day to day working life. I have taken diamonds into dealers toilets to check them for fire because it has been the only place there have been spot lighting.
Our friend David would be a point in case I think, and although he has never shared any info about the lighting it seems from looking at his photo's that the main source of color flashes is the light from his hands and the light entering the pavilion. Many old cuts have little and they should have some big bold flashes.

Bryan if you check with princess cut i think you will find stones under about 3/4ct (with 4 chevrons) have very little fire - its only once you get to say +2ct princess that you can see much fire.
Bryan here is a link to the MSS Princess cut in the videos http://www.octonus.com/oct/mss/diamPr0.html I think you would be happy to have that as a WF ACA.
Sergey can you share the chart that shows fire and frequency -I think you used it in an HRD presentation?

Garry,
do you mean HRD 2013 or Antwerp 2014 presentation?
sorry I do not remember this chart( I saw hundred's similar charts in this year. And we do some changes very often yet because I see

problem in Fire Stereo Dynamic metric ( it show reasonable difference for similar diamonds( one cut, different proportions) but has not good enough correlation with human vision when we have to compare apples with orange .)

Regarding the lighting environment - it has been carefully considered. It possibly creates more fire than usual because of the strips of lighting and orientation - but by doing so we are able to increase the number of flashes and that means the higher counts are the same for the Tolkowsky standard and any stones being compared. So it is not an unfair setup. The only thing I would add is that by playing the video's on a large screen you will see fire that you would not see in person - but Sergey's brilliant OctoNus team are able to model the sizes of flashes that should be ignored.

 

[Serg]

Pretty amazing stuff. These experiments are great. Having watched the videos first and ranked them first, I agree that those graphs (at least in terms of order) correspond to what my eyes saw.

Also, I noticed the tolk was the brightest diamond to my eyes. What does your program say?

we have not yet Subjective Brightness metrics based on Stereo movies.
Old DC LightReturn Stereo metric gives 0.98 ( Total), 0.94( Table only)
it is typical what you need increase Fire you have to reduce Brilliancy ( if Brilliancy was high as in Tolkowsky round)

I have not had time these past few days to look at some diamonds and experiment with ways to make them "normally" dirty. I believe when we can find a way to do that
But as you say Sergey, and Teobld noted, the 40.7 is brighter and brightness has always been the enemy of fire and colored flashes.
I remain stubborn and unconvinced.



Garry,
Yes , you are very stubborn in to penalty P41.2-P41.4. ( 8 years debates? but such diamonds helps me understand how stereo vision is important to grade diamond Performance. 10 years ago I was agree to penalty such diamonds then I checked many such diamonds and did not find anything wrong with such diamonds. I understood that simple IS, ASET leakage does not work, that real world is much more complicated and started Stereo Vision Research. So thanks a lot for this Debates. )

P41.2 has a little bit more Fire and a little bit less Brightness in same time.
it is normal, it is beautiful cut. what is any objective reason to penalty such cut?

You convince me neither with "Death ring" nor "Dirty Durability".

I sure( My Private Opinion based on 15 years research) it was critical mistake to penalty such diamond based on ASET, IS images. ( critical for ASGL business . AGS did not verify " ASET Leakage theory" by real Human observations tests. then they repeated same mistake with Fancy cuts)

 

[teobdl]

What distance is this modeled? As shown previously, even stereo vision sees something closer to mono at greater distances. These distances are in fact closer to real life viewing distances. How would perceived overall light return change in the 41.2 and 41.4 at greater distances? If the aset detects leakage, it would seem that at a distance there would be even less light ( and less fire?) compared to the tolk.

 

[OoohShiny]

Bryan here is a link to the MSS Princess cut in the videos http://www.octonus.com/oct/mss/diamPr0.html I think you would be happy to have that as a WF ACA.

For a noob like me that is a very interesting link, especially when one goes back to the table it is taken from!

What is this cut in the table?? http://www.octonus.com/oct/mss/diamVC2.html


(Apologies for the brief off topic )

 

[Serg]

What distance is this modeled?


I want clarify : Last movies are not Diamcalc movies. its are Vibox movies from real diamonds.

http://lexusindia.in/products/gb-ViBOX.aspx

working distance is around 350mm.


As shown previously, even stereo vision sees something closer to mono at greater distances. These distances are in fact closer to real life viewing distances. How would perceived overall light return change in the 41.2 and 41.4 at greater distances? If the aset detects leakage, it would seem that at a distance there would be even less light ( and less fire?) compared to the tolk.

As I wrote early we have not yet Stereo Subjective Brightness metric( we have not metric for Brilliancy). Our first priority is Streo Fire metric .


Leakage is not only one important factor when we speak about Brightness, Brilliancy.

take for example 2 Tolk round diamonds. 2mm and 6mm.( exactly same proportions)

6mm has more Fire, but 2 mm is brighter !

But 6mm diamond from 1m observer distance is not same as 2mm diamond from 0.33m Observer distance!
You may see great Fire in 6mm diamond from 1m if room is dark and Brilliancy is not important from 1m in dark room( from 3m Brilliancy is not important and almost absent in any light conditions)
If you want discuss about Brilliancy you have use short distances.

there are many other issues which is very important for Brilliancy metric ( Leakage , Light Return is too simple and not enough to receive adequate metric)

Brilliancy is not just Brightness . If you need Brightness you need buy Flashing LED Lamp( it is much more cheap than diamond)

 

[Serg]

Bryan here is a link to the MSS Princess cut in the videos http://www.octonus.com/oct/mss/diamPr0.html I think you would be happy to have that as a WF ACA.

For a noob like me that is a very interesting link, especially when one goes back to the table it is taken from!

What is this cut in the table?? http://www.octonus.com/oct/mss/diamVC2.html


(Apologies for the brief off topic )

we designed this cut to show possibility create easy visible Logo( pattern) .

it is sample for Maltese cross.

 

[Texas Leaguer]

Really interesting demo/survey. I think such a tool could be very useful to offer shoppers to determine what flavor of diamond they might prefer in real life.

Serg- yes my bias is certainly based on the fact that I spend my time looking at really nice rounds and princess cuts. I agree that it probably has to do with the brightness/patterning/scintillation combinations of those two shapes. And perhaps the market will start to put more emphasis on fire, particularly as the nature of indoor lighting continues to evolve in a direction that makes fire more observable. However, I hesitate to give too much weight to a beauty aspect that is only a "part time" benefit. I think I am still in the camp that prefers a balance of beauty characteristics. I think it's always going to be hard to beat a diamond that is maximized for a wide range of LP aspects in a balanced way, such as a super ideal round.

Don't get me wrong. I think fire in a diamond is awesome. It is arguably the most dramatic aspect of diamond beauty. If consumers understand more about these tradeoffs, perhaps they will collect various flavors, mrb for daily wear, a fiery fancy shape for evening, etc. See where I am going with this?

Regarding my inquiry about the graph, the deltas between the control stone and test stones are smaller for dynamic fire, a more relevant metric. Especially when calculated for a wider range of motion. That further indicates to me that balance is good, considering the tradeoffs that are being made for fire.

Garry,
Your princess does look like it would be beautiful. And while princess cut in general does not maximize fire, it has twice as much as the crushed ice cushion in the survey.

 

[Texas Leaguer]

Garry/Serg,
I am very interested in your "dirty durability" studies. I think if you could illustrate this concept vividly, it would have a huge impact on how consumers approach the ownership/maintenance of their diamonds. And could impact the selection of diamonds based upon cutting angles as well.

For me, it is hard to think of an issue that if better understood would lead to a world full of more beautiful diamonds. It would be like waving a magic wand!

My baseline guidance is always, "properly clean your diamond at least as often as you wash your car!"

 

[Texas Leaguer]

One would think dynamic fire would be more relevant to predicting real life performance than static fire, yes?

Yes, of course dynamic metric has to be more relevant.

How adaptable is this particular system to fancy shapes?

Yes.

Have you made any fire movies of any other shapes?

mainly we work with fancy cuts. Round cut is boring cut for me.

see for example
https://www.dropbox.com/s/5dc2oxly6gwtnbw/Merged3VideosCush4Cushio10.mov

To see this movie in good quality You have to download it ( Dropbox web interface significantly reduce quality)
which Cushion has more fire for You?
What cushion do you prefer on this movie ?

to receive right appearance you have to check it in stereo

Serg,
I picked up a cheap pair of 3D glasses (Universal Passive). They do not seem to make much difference in viewing the movies at the above link. I think I like the cushion that is the third stone from the left.

There were other glasses more expensive - Active type. Are those better for viewing these movies?

 

[Serg]

One would think dynamic fire would be more relevant to predicting real life performance than static fire, yes?

Yes, of course dynamic metric has to be more relevant.

How adaptable is this particular system to fancy shapes?

Yes.

Have you made any fire movies of any other shapes?

mainly we work with fancy cuts. Round cut is boring cut for me.

see for example
https://www.dropbox.com/s/5dc2oxly6gwtnbw/Merged3VideosCush4Cushio10.mov

To see this movie in good quality You have to download it ( Dropbox web interface significantly reduce quality)
which Cushion has more fire for You?
What cushion do you prefer on this movie ?

to receive right appearance you have to check it in stereo

Serg,
I picked up a cheap pair of 3D glasses (Universal Passive). They do not seem to make much difference in viewing the movies at the above link. I think I like the cushion that is the third stone from the left.

There were other glasses more expensive - Active type. Are those better for viewing these movies?

Bryan,

what Monitor and Video card did you use.

You need use ( Computer with Nvidia card + 3DTV) or ( Computer with Nvidia card + Computer Stereo monitor) + Special software(OSV https://octonus-teams.atlassian.net/wiki/display/OSVDOC/Download) of FireFox web pages with stereo movies

see details here

https://octonus-teams.atlassian.net...with+Quadro+or+GeForce+to+Samsung+3D+Smart+TV

 

[Texas Leaguer]

One would think dynamic fire would be more relevant to predicting real life performance than static fire, yes?

Yes, of course dynamic metric has to be more relevant.

How adaptable is this particular system to fancy shapes?

Yes.

Have you made any fire movies of any other shapes?

mainly we work with fancy cuts. Round cut is boring cut for me.

see for example
https://www.dropbox.com/s/5dc2oxly6gwtnbw/Merged3VideosCush4Cushio10.mov

To see this movie in good quality You have to download it ( Dropbox web interface significantly reduce quality)
which Cushion has more fire for You?
What cushion do you prefer on this movie ?

to receive right appearance you have to check it in stereo

Serg,
I picked up a cheap pair of 3D glasses (Universal Passive). They do not seem to make much difference in viewing the movies at the above link. I think I like the cushion that is the third stone from the left.

There were other glasses more expensive - Active type. Are those better for viewing these movies?

Bryan,

what Monitor and Video card did you use.

You need use ( Computer with Nvidia card + 3DTV) or ( Computer with Nvidia card + Computer Stereo monitor) + Special software(OSV https://octonus-teams.atlassian.net/wiki/display/OSVDOC/Download) of FireFox web pages with stereo movies

see details here

https://octonus-teams.atlassian.net...with+Quadro+or+GeForce+to+Samsung+3D+Smart+TV

Just using one of the PC's in the office. I guess I will have to work on the setup.

 

[Serg]

One would think dynamic fire would be more relevant to predicting real life performance than static fire, yes?

Yes, of course dynamic metric has to be more relevant.

How adaptable is this particular system to fancy shapes?

Yes.

Have you made any fire movies of any other shapes?

mainly we work with fancy cuts. Round cut is boring cut for me.

see for example
https://www.dropbox.com/s/5dc2oxly6gwtnbw/Merged3VideosCush4Cushio10.mov

To see this movie in good quality You have to download it ( Dropbox web interface significantly reduce quality)
which Cushion has more fire for You?
What cushion do you prefer on this movie ?

to receive right appearance you have to check it in stereo

Serg,
I picked up a cheap pair of 3D glasses (Universal Passive). They do not seem to make much difference in viewing the movies at the above link. I think I like the cushion that is the third stone from the left.

There were other glasses more expensive - Active type. Are those better for viewing these movies?

Bryan,

what Monitor and Video card did you use.

You need use ( Computer with Nvidia card + 3DTV) or ( Computer with Nvidia card + Computer Stereo monitor) + Special software(OSV https://octonus-teams.atlassian.net/wiki/display/OSVDOC/Download) of FireFox web pages with stereo movies

see details here

https://octonus-teams.atlassian.net...with+Quadro+or+GeForce+to+Samsung+3D+Smart+TV

Just using one of the PC's in the office. I guess I will have to work on the setup.

It is not easy assemble correctly full setup, but result is worth . I will not disappointed. we have many special stereo tests , stereo presentations , stereo movies( include Microscope high magnification stereo movies) which we may share with You.

I advice to use Nvidia Quadro( Nvidia GeForce does not support window mode)

below page gives short Overview about different setups.
https://octonus-teams.atlassian.net/wiki/display/OSVDOC/System+Requirements+and+Setup

 

[Texas Leaguer]

One would think dynamic fire would be more relevant to predicting real life performance than static fire, yes?

Yes, of course dynamic metric has to be more relevant.

How adaptable is this particular system to fancy shapes?

Yes.

Have you made any fire movies of any other shapes?

mainly we work with fancy cuts. Round cut is boring cut for me.

see for example
https://www.dropbox.com/s/5dc2oxly6gwtnbw/Merged3VideosCush4Cushio10.mov

To see this movie in good quality You have to download it ( Dropbox web interface significantly reduce quality)
which Cushion has more fire for You?
What cushion do you prefer on this movie ?

to receive right appearance you have to check it in stereo

Serg,
I picked up a cheap pair of 3D glasses (Universal Passive). They do not seem to make much difference in viewing the movies at the above link. I think I like the cushion that is the third stone from the left.

There were other glasses more expensive - Active type. Are those better for viewing these movies?

Bryan,

what Monitor and Video card did you use.

You need use ( Computer with Nvidia card + 3DTV) or ( Computer with Nvidia card + Computer Stereo monitor) + Special software(OSV https://octonus-teams.atlassian.net/wiki/display/OSVDOC/Download) of FireFox web pages with stereo movies

see details here

https://octonus-teams.atlassian.net...with+Quadro+or+GeForce+to+Samsung+3D+Smart+TV

Just using one of the PC's in the office. I guess I will have to work on the setup.

It is not easy assemble correctly full setup, but result is worth . I will not disappointed. we have many special stereo tests , stereo presentations , stereo movies( include Microscope high magnification stereo movies) which we may share with You.

I advice to use Nvidia Quadro( Nvidia GeForce does not support window mode)

below page gives short Overview about different setups.
https://octonus-teams.atlassian.net/wiki/display/OSVDOC/System+Requirements+and+Setup

I am definitely interested in being able to see this work. I will refer to your instructions and work on getting the right setup. Thanks.

 

[Garry H (Cut Nut)]

Really interesting demo/survey. I think such a tool could be very useful to offer shoppers to determine what flavor of diamond they might prefer in real life.

Serg- yes my bias is certainly based on the fact that I spend my time looking at really nice rounds and princess cuts. I agree that it probably has to do with the brightness/patterning/scintillation combinations of those two shapes. And perhaps the market will start to put more emphasis on fire, particularly as the nature of indoor lighting continues to evolve in a direction that makes fire more observable. However, I hesitate to give too much weight to a beauty aspect that is only a "part time" benefit. I think I am still in the camp that prefers a balance of beauty characteristics. I think it's always going to be hard to beat a diamond that is maximized for a wide range of LP aspects in a balanced way, such as a super ideal round.

Don't get me wrong. I think fire in a diamond is awesome. It is arguably the most dramatic aspect of diamond beauty. If consumers understand more about these tradeoffs, perhaps they will collect various flavors, mrb for daily wear, a fiery fancy shape for evening, etc. See where I am going with this?

Regarding my inquiry about the graph, the deltas between the control stone and test stones are smaller for dynamic fire, a more relevant metric. Especially when calculated for a wider range of motion. That further indicates to me that balance is good, considering the tradeoffs that are being made for fire.

Garry,
Your princess does look like it would be beautiful. And while princess cut in general does not maximize fire, it has twice as much as the crushed ice cushion in the survey.

Bryan this shows chart from OctoNus and partners shows the fire potential of various shapes, and consider various aspects of fire - princess in a rather bad light - but the MSS stones all have a spread of 3/4ct round equivalent. So there is not much fire in that sized stone - above 2ct Princess perform better.
The criteria for the chart is Average Fire Flash's sizes and it does not account number of VF's

 

[kenny]

Is 'crashed' ice from an ice truck accident?

 

[Karl_K]

I don't agree that large slow flashes are bad, an EC has a lot of them off the main steps and they are pleasing to see.
I do not like forcing all cuts to meet one criteria.
What is not optimal in one design may be optimal in another.

 

[Serg]

I don't agree that large slow flashes are bad, an EC has a lot of them off the main steps and they are pleasing to see.
I do not like forcing all cuts to meet one criteria.

Who did that?

What is not optimal in one design may be optimal in another.

 

[Karl_K]

I don't agree that large slow flashes are bad, an EC has a lot of them off the main steps and they are pleasing to see.
I do not like forcing all cuts to meet one criteria.

Who did that?

What is not optimal in one design may be optimal in another.

By labeling slow flashes as bad in the chart it implies that they are always bad.
I also think that labeling fast as good is not right.
I think by reading what you have said over the years we do not really disagree, its the presentation on the chart I disagree with.

 

[MelisendeDiamonds]

Is 'crashed' ice from an ice truck accident?

Yes, it makes you wonder if maybe Garry and Serg should proofread their posts and have their work checked and peer reviewed before it is posted here.

 

[Serg]

I don't agree that large slow flashes are bad, an EC has a lot of them off the main steps and they are pleasing to see.
I do not like forcing all cuts to meet one criteria.

Who did that?

What is not optimal in one design may be optimal in another.

By labeling slow flashes as bad in the chart it implies that they are always bad.


Label are : "Bad Fire Dynamic ", " Good Fire Dynamic"

Where did you find here any thing about "Bad or good diamonds?", "One rule for all diamonds?", Etc,...
It just Fire Dynamic.
A family car has worse dynamic than sport car. Does this statement say that Family car is worse than Sport car?

I also think that labeling fast as good is not right.
I think by reading what you have said over the years we do not really disagree, its the presentation on the chart I disagree with.

Seems, you have not any idea about context this chart.

Garry, please either explain reason of publication the chart by you .( explain full context) . It is not good idea to take on chart from 2 hours presentation without any explanations of chart proposal .

 

[kenny]

Is 'crashed' ice from an ice truck accident?

Yes, it makes you wonder if maybe Garry and Serg should proofread their posts and have their work checked and peer reviewed before it is posted here.

In this case I think it's just an English-proficiency thing.

That said, I feel a bit bad about making a funny.
I'm certain the author's English is WAAAAY better than my Spanish, the only other language I 'speak'.

 

[Serg]

Is 'crashed' ice from an ice truck accident?

Thank You.

 

[kenny]

Is 'crashed' ice from an ice truck accident?

Thank You.

Serg, I hope you're not offended if it was you who wrote crashed ice instead of crushed ice.
I have nothing but great respect for you and your work and frankly for anyone who learns this crazy language we call English.