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Differences in Idealscope and AGS Cert Images

japroffitt1

japroffitt1

Rough_Rock
Joined
Apr 21, 2012
Messages
25
Ok, so I just ordered a diamond from James Allen that I think is a pretty good stone and I have been using it to compare against diamonds locally. It is definitely more beautiful than any diamond I have seen in a B&M store, so at this point I think I am going to stick with it. However, JA does have a great return policy so my search for the perfect diamond for me will not end until that return period has expired.

This is the diamond that I have bought:
http://www.jamesallen.com/diamonds/G-SI1-Ideal-Cut-Round-Diamond-1452929.asp?b=16&a=12&c=77&cid=131

Shape: Round
Carat weight: 0.76
Cut: Hearts & Arrows Ideal
Color: G
Clarity: SI1
Certificate: AGS
Depth: 61.3%
Table: 55.5%
Polish: Ideal
Symmetry: Ideal
Girdle: Thin to medium
Culet: None
Fluorescence: Negligible
Measurements: 5.90*5.93*3.62
Crown Angle: 34.0
Crown %: 15.10
Pavilion Angle: 40.9
Pavilion %: 43.30

The couple questions I have are in regards to the AGS report light return images on their certificates. I want to know which is a more 'ideal' cut diamond. I have attached two different photos below the first being the image for my diamond and the second for another that I have found. In the first image there is contrast (blue) coming off and attached to both sides of the arrows and there is a red circle in the middle of the diamond. In the second image the blue are much smaller points and not connected to the arrows and there is green in the middle. I think the smaller blue points not connected to the arrows are more ideal but I am somewhat puzzled by some diamonds having red circles in the middle vs green circles.

My other question is why on the idealscope image, the third image below, do the contrast points attached to the arrows in the AGS report photo not show up? The idealscope image is of the same diamond in the first picture below.

1452929id.jpg
 

Attachments

Anyone have any input?
 
the ASETs on the grading reports are scans of a 3-d model of the diamond whereas the idealscope image is an actual picture of the diamond.

red vs green in the middle is not an issue...there is a thread that explains it somewhere.

I don't think you can say from the computer generated ASETs that one is more ideal than the other. they both look great but if you are happy with your diamond I see no reason to return it!
 
I think AGS made a mistake.
It is unlikely with those proportions that you could achieve anything like that look under an ASET scope.
I would ask JA to take an ASET photo and I will bet $5 it backs up the ideal-scope pic.
 
It is quite odd, but I have seen quite a number of AGS light return maps that look similar to the first one. I had kind of assumed that it may just be the software/camera/lighting making it do that, but just wanted make sure that they weren't something to avoid or anything like that. I definitely think the second AGS light return map is much more visually appealing.
 
I am pretty sure AGS took the 40 deegree head obstruction image, not the one with 30 degree.
Any other folk want to weigh in on that?
It is clearly a very fine stone.
Jappro I hope you do not reject it because of such a mess up?
 
I was half right (60% wrong).
Here is a reply from Peter Yantzer and Jason Quick (aka Q) from AGS Lab.

Hi Pete,
I took a look at Garry’s Pricescope and here’s what’s going on.
Per, the James Allen website, the stone’s proportions are as follows:
Diameter: 5.90
Table: 55.5
Crown: 34.0
Pav: 40.9
Star: 58%
LG: 77%
Plugging this into Diamcalc, we get this for a standard ASET (30 degrees of obscuration):
After Changing the obscuration from 30 degrees to 34 degrees we get this:
Which agrees closely with the AGSL Report (as posted on Pricescope) :
There seems to be tight agreement between the virtual image and the report image, so I don’t think there’s a mistake.
However, Garry is probably not aware that our Report ASET images are based off of 33.5 degrees of blue obscuration because this ASET was deemed to best represent our cut grade system which utilizes ASET30 and ASET40 maps with relative weightings of about 66% ASET30 and 34% ASET 40 (.66 * 30 + .34*40 = .334).
Q out

Q didn't mention but I will mention that the ray tracer calculates all values at exactly ASET 30 blue and ASET 40 blue. The computer created image for AGSL reports is generated and printed at ASET 33.5 blue per the explanation above.
Heartily,
Peter and Jason

So folks, I have learned something, and I bet a lot of other experts did not know that either.
All the images you see that are based on photo's have less blue and more red because the angle of the photograhic set up is different.

So the stone does have the type of image we all like, with way less blue if it were photographed in a normal set up which are all based on 30 degrees of blue / obscuration. I know because i modeled it and get the right result - and for the record - the 34 and the 40 degree images are laomost identical.
 
Garry H (Cut Nut)|1336109050|3187214 said:
I was half right (60% wrong).
Here is a reply from Peter Yantzer and Jason Quick (aka Q) from AGS Lab.

Hi Pete,
I took a look at Garry’s Pricescope and here’s what’s going on.
Per, the James Allen website, the stone’s proportions are as follows:
Diameter: 5.90
Table: 55.5
Crown: 34.0
Pav: 40.9
Star: 58%
LG: 77%
Plugging this into Diamcalc, we get this for a standard ASET (30 degrees of obscuration):
After Changing the obscuration from 30 degrees to 34 degrees we get this:
Which agrees closely with the AGSL Report (as posted on Pricescope) :
There seems to be tight agreement between the virtual image and the report image, so I don’t think there’s a mistake.
However, Garry is probably not aware that our Report ASET images are based off of 33.5 degrees of blue obscuration because this ASET was deemed to best represent our cut grade system which utilizes ASET30 and ASET40 maps with relative weightings of about 66% ASET30 and 34% ASET 40 (.66 * 30 + .34*40 = .334).
Q out

Q didn't mention but I will mention that the ray tracer calculates all values at exactly ASET 30 blue and ASET 40 blue. The computer created image for AGSL reports is generated and printed at ASET 33.5 blue per the explanation above.
Heartily,
Peter and Jason

So folks, I have learned something, and I bet a lot of other experts did not know that either.
All the images you see that are based on photo's have less blue and more red because the angle of the photograhic set up is different.

So the stone does have the type of image we all like, with way less blue if it were photographed in a normal set up which are all based on 30 degrees of blue / obscuration. I know because i modeled it and get the right result - and for the record - the 34 and the 40 degree images are laomost identical.
Click to expand...

Garry, Did you mean to post images? It seems your reply has a spaces for images but they are not there. Could you please post them so I could take a look.

Thanks
 
Garry H (Cut Nut)|1335990510|3185947 said:
I think AGS made a mistake.
It is unlikely with those proportions that you could achieve anything like that look under an ASET scope.
I would ask JA to take an ASET photo and I will bet $5 it backs up the ideal-scope pic.
Click to expand...


So, who do you owe $5.00? Or is it $2.50 because you were only half right (60% wrong)? :lol:

Great information, thanks for taking the time to investigate and post the results for us here! =)
 
Christina...|1336746723|3192972 said:
Garry H (Cut Nut)|1335990510|3185947 said:
I think AGS made a mistake.
It is unlikely with those proportions that you could achieve anything like that look under an ASET scope.
I would ask JA to take an ASET photo and I will bet $5 it backs up the ideal-scope pic.
Click to expand...


So, who do you owe $5.00? Or is it $2.50 because you were only half right (60% wrong)? :lol:

Great information, thanks for taking the time to investigate and post the results for us here! =)
Click to expand...

hahahaha - are you going to the Vegas GTG Christina - I will buy you a drink thats worth $2.50!
I have never seen a commercially available ASET with those lighting angles / structure.

Oh, and to the OP - I never had pictures - was referring to yours.
 
I believe Jason once mentioned lP grades in fancies are based on ASET 40 blue.
Extra care in the grades?
I learned it when I was trying to balance contrast (blue) with primary light source (red) on a design.

I do understand taking extra measures in the grading process (eg ASET 40 vs ASET 30), but don't understand the logic of not taking tilts in the equation.

Hopefully one day....
 
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