AGS ASET Info and Photos from JCK

[WinkHPD]

P.S. Someone will slap me if I was wrong!

 

[belle]

Date: 6/6/2005 4:13:59 PM
Author: denverappraiser
I need to do some homework in analyzing these things. There''s quite a bit of data inculcated in that and I''m not sure what to make of it. Belle, how did you produce the model? That looks like DiamCalc but ASET isn''t one of the options in mine.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

oh...i cannot take credit for the model, it is one sir john posted as a reference. i just happened to notice the striking similarities between the two and wanted to show them side by side.

there is more discussion on aset images here that may be of interest.

 

[denverappraiser]

Here''s a version of that same stone with the transmitted light blocked off (which is what the desktop model does). the Yellows and oranges have got to be coming from my camera settings. This is going to take a bit of practice - Rather like the Ideal Scope and H&A pics, I think it will have it''s own set of techniques to get decent images.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[JohnQuixote]

Date: 6/6/2005 6:07:45 PM
Author: denverappraiser

All in all this looks VERY different from the photo that John took at the booth.

Neil, I took the one at the booth through the eyepiece of the desktop model, with weird exhibit hall lighting. Jim Caudill has designs on standardizing the lighting environment for photographic and casual viewing purposes in the near future.

 

[JohnQuixote]

A couple more photos of the desktop model.

 

[JohnQuixote]

The centering arm gets the diamond to its correct placement.

 

[denverappraiser]

John,

Here''s a nice looking stone.

I''m using the light that they are selling at the booth. I don''t think it''s the best but it seems to work pretty well.

Neil

 

[denverappraiser]

Here''s the same stone with the transmitted light blocked off and a VERY bright light.

 

[denverappraiser]

For the benefit of those who are lurking, this one is:

1.10cts.
6.69 x 6.72x4.07mm
56.4% Table
34.7 crown
40.7 aPavilion
v. small culet
thin-medium girdle

 

[WinkHPD]

Amazing how much more this picture tells you. The ideal scope shows a nice stone that is obvously tilted a little for its photo. This photo also appears to be a little tilted, but that will be corrected with the desk top model that allows us to lay the stone on its table so that any apparent tilt will indeed be in the stone not the holder.

Here is what I see in the above stone. It has lots of red and perhaps a little more green that we would like. I am betting that this stone will NOT get an AGS 0 cut grade but probably a one or a two, you can tell me how far off I am if this stone has one of the new AGS papers. Since the table reflection in the center of the stone is green we know that the pavilion angle is less than 40.768 degrees. (If it were 40.768 degrees or greater the table reflection would be red, interesting, yes?)

Also, since the stone has a great amount of red with some good blue in the red for contrast this stone should show a great deal of dynamic brilliance that POPS as the stone moves even small degrees. This stone should SIZZLE!

The black shows us only minimal amounts of leakage, this is a good looking stone!

Wink

P.S. Niel, you have the stone in hand, how close am I?

 

[denverappraiser]

Wink,

This stone has a AGS-0 report dated Jan 24, 2005. I'm not sure when they started using the new system on the reports but in looking it up on the little charts that were given at the show, I think it will still make the grade. It's a very pretty stone. Your comment about the green table is interesting. Can you please explain?

I'm a bit concerned about the tabletop approach on the piece of glass with the transmitted light blocked. I put a bit of effort into considering that with taking ideal scope photos, which have the same problems, and found it to mess with the image. In the case of the ASET images, I think it will be worse. The problem is the glare on the glass. The low angle light will reflect almost entirely off of the surface of the glass while the steep angles are almost completely transmitted. I don't know anything about the glass they are using for this tool but it seems terribly important. Light that reflects back into the cone will contaminate the rest of the colors as well. My conclusion in the case of the IdealScope was that a different kind of leveling tool was required. I've designed one but I haven't built it yet because I wanted to see how they handled this issue with the new AGS scope. The tabletop model isn't yet available and it's therefore impossible to play with it and compare images to photos taken under different conditions. My gut feeling is that the handheld variety has better potential for photos than the desktop model although the leveling technique will be important. It's also interesting to notice how easy it is to spot that the stone crooked in the photo. As you know, much of my interest in this kind of thing has to do with examining mounted diamonds where proper leveling will be extremely difficult.

Here's the same stone taken from below on a sheet of glass. I see far less green. I don't really understand the weird halo effect around the crown either.

Neil

 

[Michael_E]

I think that this is a neat toy to play around with, but I also think that the use of this instrument to analyze the optics of a stone are a bit more limited than some of you realize. This instrument is basically an Idealscope with colored rings at various heights that indicate certain angles of light entering the stone. Those angles are not distinct cut-offs and the difference between the cosine squared at 44 degrees and that at 46 degrees is very slight, yet light entering from 46 degrees will be green and eventually be considered a bad thing and to be avoided. Maybe I''m dense, but it seems to me that light entering from any angle and making it to your eye plays a part in the brightness of a stone and certainly plays a part in the fire inherent in a given stone. I doubt that anyone here could pick between two stones, one stone that was cut so that it was showing green and another so that it was showing red due to their slightly different angles. This goes for the blue/red and black/blue areas as well.
The other thing that seems obvious to me, please straighten me out if I am wrong here, is the same problem that is inherent with the Idealscope and that is by being as close to the stone as you are when viewing it, and using magnification, you are getting a picture of the stones reflective patterns that are not the same as what you would get if the stone were at arms length. Leakage for instance, does not occur at just one angle at the points that show leakage. It occurs at various angles around that area forming a "cone" of leakage that has some narrow included angle and neither the Idealscope or this ASET scope can give you any idea of the included angle of the light leakage or reflections that are what you will ACTUALLY be seeing when you are holding the stone at arms length. If the included angle of the light leakage "cone" is a very small angle and the angle away from perpendicular to the table that those leakage areas are directed is over a couple of degrees, then you will never see the "leakage" usless you tilt the stone and then you will only see one very small spot at a time. I''m afraid that both of these devices, since they capture an image so close to the stone, really don''t give you as much of an ability to analyze the stone as you may be thinking they do.
On a more postive note, if you wanted to have the same imaging capabilities with the hand held version it would be an easy rework to place a clear plastic or glass plate across the end of the instrument and then hold the stone against it with a small black foam filled cone. This would allow you to hold the table flat against the clear plate and block any back lighting. Same thing would work with the Idealscope.

 

[denverappraiser]

Michael,

This is definitely an artificial viewing environment but that doesn’t mean that it isn’t useful. X-ray’s are artificial as well but doctors seem to find them helpful in the right circumstances. I certainly agree that it’s important to be careful about starting with a very narrow observation like this and generalizing from that but there is clearly some interesting data inculcated in these images and there is some possibility that that data will be useful in analyzing diamonds. Wink’s observation about the green table being a clue to the pavilion angle is a wonderful case in point. This is something that is decidedly difficult to measure directly (especially on mounted stones), is of definite interest and is not easily observable with any other tool that I’m aware of.

I certainly agree that it would be a mistake to conclude that green=bad or to make similar blanket statements based on these images. I’ll even agree that leaping to this sort of conclusion is the general tendency of many people. It’s not magic, it’s just another piece of the puzzle. Surely you agree that it’s a pretty interesting piece.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[Michael_E]

Neil,
It is indeed very interesting. I just think that, as you say, it is one piece of the puzzle and that looking at these images should be done with that in mind. If a stone is an AGS 0 and the Ideal scope or ASET image looks good, then that stone is probably a VERY nice stone. My difficulty lies in the human desire to have "the best" and to require having this backed up by other opinions, certs and images from this scope and that, when in reality neither they or anyone else can tell the difference, in terms of "beauty", between an AGS 0 and an AGS 2 and that having a little green or black in one of these images is taken to mean something, which it may or may not, depending on other factors which are not taken into account. It just feels to me as if the sales hype is being institutionalized around things other than how the stone actually looks to the buyer. Using these images to make pronouncements about how these stones will actually look will only really work if there are profound areas that show black, blue or green, (the green is in doubt in my mind), and to look at small differences and claim that one stone is better than the next seems more attuned to sales than to actually being able tell anything about the way that the stone will look on your hand.

 

[JohnQuixote]

Date: 6/7/2005 6:52:15 PM
Author: Michael_E
I think that this is a neat toy to play around with, but I also think that the use of this instrument to analyze the optics of a stone are a bit more limited than some of you realize. This instrument is basically an Idealscope with colored rings at various heights that indicate certain angles of light entering the stone. Those angles are not distinct cut-offs and the difference between the cosine squared at 44 degrees and that at 46 degrees is very slight, yet light entering from 46 degrees will be green and eventually be considered a bad thing and to be avoided. Maybe I'm dense, but it seems to me that light entering from any angle and making it to your eye plays a part in the brightness of a stone and certainly plays a part in the fire inherent in a given stone. I doubt that anyone here could pick between two stones, one stone that was cut so that it was showing green and another so that it was showing red due to their slightly different angles. This goes for the blue/red and black/blue areas as well.

Hi Michael. I believe for close comparison purposes, as will be made with vendors’ stones for instance, the standardized desktop model is repeatable as it relates to your 44-46 degree scenario. For that matter, green is not considered bad – I am not sure where that perception came from – though obviously it is not as desirable in this metric as red.

Your speculations about someone picking out the difference in static red return versus static green return are well-taken, however you may be overlooking the fundamental premise in going to this multi-colored system: The ability to identify contrast. Here are cosine squared images of 2 stones. They are identical, except that a 30 degrees cone of obscuration, equivalent to an observer’s head, is present in the one on the right.

Contrast is part of the foundation of this system, and deservedly so.

 

[JohnQuixote]

The other thing that seems obvious to me, please straighten me out if I am wrong here, is the same problem that is inherent with the Idealscope and that is by being as close to the stone as you are when viewing it, and using magnification, you are getting a picture of the stones reflective patterns that are not the same as what you would get if the stone were at arms length. Leakage for instance, does not occur at just one angle at the points that show leakage. It occurs at various angles around that area forming a 'cone' of leakage that has some narrow included angle and neither the Idealscope or this ASET scope can give you any idea of the included angle of the light leakage or reflections that are what you will ACTUALLY be seeing when you are holding the stone at arms length. If the included angle of the light leakage 'cone' is a very small angle and the angle away from perpendicular to the table that those leakage areas are directed is over a couple of degrees, then you will never see the 'leakage' usless you tilt the stone and then you will only see one very small spot at a time. I'm afraid that both of these devices, since they capture an image so close to the stone, really don't give you as much of an ability to analyze the stone as you may be thinking they do.

I can’t comment on what you think others are thinking

but the analysis that is occurring has a well-disclosed foundation, including aspects of distance. The foundation of the new AGS system identifies it as designed around ‘a close viewing distance.’ Reasoning? There are many, but key is the fact that the ability to discern cut quality decreases with distance. Most importantly, the effect of the observer’s head decreases with distance – and a stone of fine make next to a stone of inferior make are much closer in appearance without that all-important obscuration providing contrast. The distance of 25 cm (just short of 10”) was chosen for many reasons, having to do with standardization in other visual fields and physical/optical properties of human vision. Even without those reasons, it seems practical in my experience: If you notice a sparkly diamond and ask someone to show it to you I would suspect that the general tendancy is to view it at about 10 inches away or perhaps just slightly further.

Of course you have a point in that this is not a metric for every possible distance, environment, etc. However, this is a very practical baseline to me and - importantly - with the definitions AGS has been careful to give in their foundation it appears to have more teeth than any prior 'performance assesment device.'

 

[JohnQuixote]

On a more postive note, if you wanted to have the same imaging capabilities with the hand held version it would be an easy rework to place a clear plastic or glass plate across the end of the instrument and then hold the stone against it with a small black foam filled cone. This would allow you to hold the table flat against the clear plate and block any back lighting. Same thing would work with the Idealscope.

Good idea. It would save one some $. Desktop model for non-members is a grand. The problem is that the hand held version has such a tiny viewing aperture. I am tempted to ask Neil how in ‘tarnation’ (Texas word – yee-haw) he got those shots.

By the way Neil, with regard to glare, I remembered prior conversations we have had and asked Jim about that. First, the desktop ASET has dual anti-glare treatment on the bottom side 2mm thick and single treatment on the top. He also talked a whole bunch about angle of incidence and the work they have done with the cone to avoid glare/reflection/bad hair day/etc, but I had eaten a big burrito for lunch and the details are fuzzy in my memory.

 

[JohnQuixote]

Date: 6/7/2005 7:58:07 PM
Author: Michael_E
Neil,
It is indeed very interesting. I just think that, as you say, it is one piece of the puzzle and that looking at these images should be done with that in mind. If a stone is an AGS 0 and the Ideal scope or ASET image looks good, then that stone is probably a VERY nice stone. My difficulty lies in the human desire to have 'the best' and to require having this backed up by other opinions, certs and images from this scope and that, when in reality neither they or anyone else can tell the difference, in terms of 'beauty', between an AGS 0 and an AGS 2 and that having a little green or black in one of these images is taken to mean something, which it may or may not, depending on other factors which are not taken into account. It just feels to me as if the sales hype is being institutionalized around things other than how the stone actually looks to the buyer. Using these images to make pronouncements about how these stones will actually look will only really work if there are profound areas that show black, blue or green, (the green is in doubt in my mind), and to look at small differences and claim that one stone is better than the next seems more attuned to sales than to actually being able tell anything about the way that the stone will look on your hand.


But Michael, there is MUCH change afoot with regard to proportions versus performance. New AGS(X) can have a distinctly different look because it's not constrained to numbers from a Helium scan. There are multiple factors now going into the grade weighted on much more than crown/pav combos. Given all principles, including the standard distance, obscuration, contrast, leakage, appearance as distance varies, spread, girdle thickness, etc. can you say that new AGS2 will look the same as AGS0 in this metric?

I am not making a definitive statement about this since I have yet to play with our first batch of new AGS-graded diamonds (hot off the cert-line). Tomorrow I have about 170 to mess with. We all have yet to make observations in the new system. We’ll see – but it’s not just about proportions anymore.

 

[denverappraiser]

Date: 6/7/2005 8:13:11 PM
Author: JohnQuixote

By the way Neil, with regard to glare, I remembered prior conversations we have had and asked Jim about that. First, the desktop ASET has dual anti-glare treatment on the bottom side 2mm thick and single treatment on the top. He also talked a whole bunch about angle of incidence and the work they have done with the cone to avoid glare/reflection/bad hair day/etc, but I had eaten a big burrito for lunch and the details are fuzzy in my memory.

Glare and angle of incidence are clearly important. I also asked Jim about it but I didn''t get to actually look at the piece of glass. He was quite busy when I visited and I''m just some podunk appraiser from Colorado. I think you got a better interview than I did.

the $1000 price tag seems like a real problem for this to get much penetration into the market but I agree that it can be done with the little one if it can be established what is desireable. Our discussions on leveling the IdealScope for photos are clearly applicable, as are the differences associated with a view through glass. We''ve added the optics of the glass to the issue. The last two images are of the same stone, one through glass and one without. There are some clear differences in the coloration.

To take the final picture, I cut the bottom off of a standard Kodak type film can and taped it to the ASET with electrical tape. This allowed me to set my camera on the desk facing straight up and balance the ASET directly on the lens. I put a sheet of glass on top of that and put a pen cap from a Sharpie over the top of the stone to block out the transmitted light. I suspect that replacing the glass with the correct material would result in a pretty good replication of the tabletop unit for photographic purposes and for a bunch less money unless you use a special Gemological sharpie (available only from Gem-A).

What do you think of the green table? any other interesting observations?

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[JohnQuixote]

Date: 6/7/2005 6:00:55 PM
Author: Wink
Amazing how much more this picture tells you. The ideal scope shows a nice stone that is obvously tilted a little for its photo. This photo also appears to be a little tilted, but that will be corrected with the desk top model that allows us to lay the stone on its table so that any apparent tilt will indeed be in the stone not the holder.

Here is what I see in the above stone. It has lots of red and perhaps a little more green that we would like. I am betting that this stone will NOT get an AGS 0 cut grade but probably a one or a two, you can tell me how far off I am if this stone has one of the new AGS papers. Since the table reflection in the center of the stone is green we know that the pavilion angle is less than 40.768 degrees. (If it were 40.768 degrees or greater the table reflection would be red, interesting, yes?)

Also, since the stone has a great amount of red with some good blue in the red for contrast this stone should show a great deal of dynamic brilliance that POPS as the stone moves even small degrees. This stone should SIZZLE!

The black shows us only minimal amounts of leakage, this is a good looking stone!

Wink

P.S. Niel, you have the stone in hand, how close am I?

Though it''s nice that we''re enthusiastically attacking interpretation, I think further study - especially with regard to standardizing lighting environment - is going to be necessary before we can give detailed assesment.

For now I would merely offer that this is a high performing diamond, based on the amount of light returned (not escaping) in Neil''s setup, regardless of hue or saturation. I would refrain from putting forward any more until we know more about illumination and placement using the hand-held unit (let''s remember the 44-46 degree variance Michael brought up).

 

[JohnQuixote]

Date: 6/7/2005 8:33:25 PM
Author: denverappraiser

What do you think of the green table? any other interesting observations?

The green in the center is as Wink noted: The 40.7 PA makes sense, because less than 40.768

results in that fascinating green dot (come-on guys - thousandths? please shoot me now!). Wink, that was on a chart for 57% table. Do you recall if 56% table (and others) result in this too?

 

[JohnQuixote]

Date: 6/7/2005 8:33:25 PM
Author: denverappraiser

To take the final picture, I cut the bottom off of a standard Kodak type film can and taped it to the ASET with electrical tape. This allowed me to set my camera on the desk facing straight up and balance the ASET directly on the lens. I put a sheet of glass on top of that and put a pen cap from a Sharpie over the top of the stone to block out the transmitted light. I suspect that replacing the glass with the correct material would result in a pretty good replication of the tabletop unit for photographic purposes and for a bunch less money unless you use a special Gemological sharpie (available only from Gem-A).

Jimminy Cricket, Neil !

You said you wanted a new avatar while we were in Vegas.

I suggest you choose one of these:

 

[denverappraiser]

Centering the stone is nicely solved by Garry''s photo trays although I notice that the footprint of the ASET is just enough bigger to make them not directly applicable.

The little voice in my head keeps saying that the answer here is something similar to the photo trays with a leveling tool. Y''all talked me out of this photo from below technique a year ago when i brought it up and all of the same issues still apply. The optics of the plate are important.

At least you''ve got to admit that it''s a pretty good image for a zero budget.

Neil McGyver
Amateur Inventor

 

[WinkHPD]

Date: 6/7/2005 8:55:01 PM
Author: JohnQuixote

Date: 6/7/2005 8:33:25 PM

Author: denverappraiser


What do you think of the green table? any other interesting observations?

The green in the center is as Wink noted: The 40.7 PA makes sense, because less than 40.768

results in that fascinating green dot (come-on guys - thousandths? please shoot me now!). Wink, that was on a chart for 57% table. Do you recall if 56% table (and others) result in this too?

I don''t remember for sure if the table was the defining difference, I think not but could be wrong. I just remember Peter giving credit to his mathmatical geniuses in the back of the room for the 3 digit angle at which the dot changed from red to green.

The next morning Gary Holloway took the diamond off his wife''s finger and said here, play with this. The table reflection was green until you pushed the stone just a tiny bit into the ASET hand held then it jumped to red. Gary said this was because his wife''s pailion angle was right on the border of the the 40.768 angle and that the actual placement of the stone affected exactly how the light reacted. What is important here is not the .768 but the FACT that we get a great idea of where the angle is, either below or above that 40.7 area.

Niel, you should be able to call AGS and find out what the new paper would be on that stone since it was graded less than six months ago and I believe after the time when they started keeping data on both grading scales.

Great conversation going here. It will be fun to come back to in a year or so and see where we stand on our understanding of this new system. We will definitely have refined our knowlege by then.

Wink

 

[WinkHPD]

Date: 6/7/2005 8:58:09 PM
Author: JohnQuixote

Date: 6/7/2005 8:33:25 PM

Author: denverappraiser


To take the final picture, I cut the bottom off of a standard Kodak type film can and taped it to the ASET with electrical tape. This allowed me to set my camera on the desk facing straight up and balance the ASET directly on the lens. I put a sheet of glass on top of that and put a pen cap from a Sharpie over the top of the stone to block out the transmitted light. I suspect that replacing the glass with the correct material would result in a pretty good replication of the tabletop unit for photographic purposes and for a bunch less money unless you use a special Gemological sharpie (available only from Gem-A).

Jimminy Cricket, Neil !


You said you wanted a new avatar while we were in Vegas.


I suggest you choose one of these:

SPOT ON! Niel, you and Jim getting to play together in his garage could make some GREAT stuff for us small jewelers.

"No Mrs. Got Rocks. I do not have the $25,000 version of the Sarin scope to give you all of those numbers, but I do have the Jim/Niel created film canister and duct tape photo lab that shows you all of the pertinent metrics. You can take one home for only $19.95 and take all of your own photos if you like or I can take them for you here for only $29.95."

(Jim is the AGS equipment guy, some of what he showed us in developement got its start in his garage.)

Way to go Niel!

Wink

 

[strmrdr]

Is the red vs green center a quality/performance issue or a personality issue?
How is it considered when assigning the cut grade?
Paul often cuts his diamonds with a 40.5 pavilion angle are they going to be downgraded under the AGS system?

 

[WinkHPD]

Date: 6/8/2005 9:37:27 AM
Author: strmrdr
Is the red vs green center a quality/performance issue or a personality issue?
How is it considered when assigning the cut grade?
Paul often cuts his diamonds with a 40.5 pavilion angle are they going to be downgraded under the AGS system?

No, it is an informational issue. 40.5 is lower than what Paul usually cuts I believe, but within the parameters of the AGS ideal if I remember correctly. Pauls stones are still receiving the coveted AGS 0 cut grade. I do not think that the green/red table reflection will be anything other than an interesting bit of information that can be instantly perceived from looking at the image. I just thought it a fascinating bit of trivia that was presented to us at the AGS lecture at their laboratory and was sharing it with you. Later I will try to show you part of the charts that were given to us at AGS, it will be much more relevant when seen with other images than when taken out of context.

While light from the 0 - 45 degree angles will not be as bright as the light from 45 to 75 degrees it is still an important part of what needs to happen in the stone for it to proform well. The green light should be minimal when possible but is certainly better than no light or "leakage" as it is often called. Like light from the blue area of 75 to 90 degrees it plays a part in the contrast that makes a stone dynamic and lively. The contrast obviously will not be as dramatic as that from the obscuration area, but will add to the look of the stone in a positive manner.

Wink

 

[JohnQuixote]

Date: 6/8/2005 9:37:27 AM
Author: strmrdr
Is the red vs green center a quality/performance issue or a personality issue?
How is it considered when assigning the cut grade?
Paul often cuts his diamonds with a 40.5 pavilion angle are they going to be downgraded under the AGS system?

Green is not bad, depending on the size and distribution of those areas in an image. It is one of the two vehicles whereby brightness contrast effects are produced (the other is leakage). A diamond like this one is drawing a majority of light from high angles, so the green over the culet should enhance contrast in a positive way.

 

[denverappraiser]

Date: 6/8/2005 8:30:06 AM
Author: Wink


Neil, you should be able to call AGS and find out what the new paper would be on that stone since it was graded less than six months ago and I believe after the time when they started keeping data on both grading scales.

AGS reports that this stone would get a AGS-0 grade under their new performance grading system as well.

Does this make it a quadruple-zero?

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[WinkHPD]

Awesome! I stand happily corrected in my guess that it would not. I thank you for taking the time to make the call.

Wink