- Joined
- May 3, 2001
- Messages
- 7,516
Date: 1/9/2006 6:21:01 PM
Author: valeria101
My post wasn't too clear... I picked an idea from way up the thread without mention: that that choices based on taste among goods of similar quality are difficult via ASET (or reflector tools in general).
Date: 1/9/2006 6:32:02 PM
Author: Wink
... both (AGS0 princess) have some nice red, some great contrast and unlike the rounds, they gather more light from the ambient light than would be acceptable for an AGS 0 round.
Date: 1/9/2006 7:16:33 PM
Author: valeria101
Date: 1/9/2006 6:32:02 PM
Author: Wink
... both (AGS0 princess) have some nice red, some great contrast and unlike the rounds, they gather more light from the ambient light than would be acceptable for an AGS 0 round.
(half joke) - green on the side, a bit of red in the middle and a sprinkle of contrast here and there ... wait a minute, that''s how the round scare looks like too!
Any chance to decide on brilliance in a consistent way across shapes? Is IS better at this (with one color instead of three?).
... No, I don''t really know what I am asking abut.
Date: 1/9/2006 7:16:33 PM
Author: valeria101
Date: 1/9/2006 6:32:02 PM
Author: Wink
... both (AGS0 princess) have some nice red, some great contrast and unlike the rounds, they gather more light from the ambient light than would be acceptable for an AGS 0 round.
(half joke) - green on the side, a bit of red in the middle and a sprinkle of contrast here and there ... wait a minute, that''s how the round scare looks like too!
Any chance to decide on brilliance in a consistent way across shapes? Is IS better at this (with one color instead of three?).
... No, I don''t really know what I am asking abut.
PS. about leakage markings ... I thing you are 100% right - at least according to the DC (remember the versions of Gilbertonscope plots - with and w/o white background light? - same can easily be done with the ASET scheme so that the two light maps become directly comparable. Is the hand held ASET supposed to be used differently than the IS?Date: 1/10/2006 9:16:23 AM
Author: Wink
So, is there a consistent way accross shapes to evaluate brilliance? Yes, and no. [....]
Each shape will have its own patterns, and it will require study and effort to learn what are the better patterns for each shape, ...
That''s what I was afraid to hear - that it takes experience to read these images, and that they are not a true shortcut to judging cut quality w/o knowing your diamonds first. This may be wrong - but isn''t precisely this what the reflector tools promise (at least the IS - which is meant as a consumer''s aid).![]()
Is this also a potential difference between the IS and ASET - what they are good for and to whom?
Date: 1/10/2006 9:41:54 AM
Author: sylvesterii
exactly what I was thinking too!. how is it bad for a round when the princess is great, but the explanation provided by wink seems to make sense. Plus, princess cut stones just can't perform as well. so imagine how BAD a BAD princess stone would perform...
The thing is that above a certain size, princess-cuts have better overall light performance than rounds.Date: 1/10/2006 10:24:38 AM
Author: valeria101
I wonder if statements like these (''princess are supposed to be worse than rounds'' and ''a fancy cut looks great under ASET when it matches a BAD round'' etc) are anywhere near what the makers of ASET and other reflector tools had in mind to begin with.![]()
Date: 1/10/2006 10:27:32 AM
Author: Paul-Antwerp
The thing is that above a certain size, princess-cuts have better overall light performance than rounds.
Live long,
Paul,
Would you please explain this? What do you mean by overall light performance?
I do not believe that princess are supposed to be worse than rounds, and I do not believe that the bad round comes anywhere close to matching the princess cut. I believe that the princess cut patterns are different in many ways than the round patterns, but that is okay, princess cuts ARE different than rounds. I fear I have not done a good job explaining things if you believe the above statement to be true.Date: 1/10/2006 10:24:38 AM
Author: valeria101
I wonder if statements like these (''princess are supposed to be worse than rounds'' and ''a fancy cut looks great under ASET when it matches a BAD round'' etc) are anywhere near what the makers of ASET and other reflector tools had in mind to begin with.![]()
Hi Neil,Date: 1/10/2006 11:36:19 AM
Author: denverappraiser
Date: 1/10/2006 10:27:32 AM
Author: Paul-Antwerp
The thing is that above a certain size, princess-cuts have better overall light performance than rounds.
Live long,
Paul,
Would you please explain this? What do you mean by overall light performance?
Neil Beaty
GG(GIA) ISA NAJA
Professional Appraisals in Denver
Date: 1/10/2006 1:26:19 PM
Author: Wink
And an editorial comment from AGS
Okay, for the princess cut photos, clearly picture #1 on the left is the better looking diamond. Great pattern of on/off contrast throughout the diamond. The stone on the right has very little contrast and something wierd is going on in the corners. I would love to see these two stones face up, but I am betting the one on the right is NOT very pretty.Date: 1/10/2006 1:18:15 PM
Author: Wink
I am going to put up a couple more slides from the AGS presentation and come back later to see what the discussion has been.
Here are ETAS images that show the probability of seeing (or not seeing) light sources for 4 stones in varying sizes.Date: 1/10/2006 2:13:53 PM
Author: Paul-Antwerp
Hi Neil,Date: 1/10/2006 11:36:19 AM
Author: denverappraiser
Paul,Date: 1/10/2006 10:27:32 AM
Author: Paul-Antwerp
The thing is that above a certain size, princess-cuts have better overall light performance than rounds.
Live long,
Would you please explain this? What do you mean by overall light performanceNeil Beaty
GG(GIA) ISA NAJA
Professional Appraisals in Denver
Did you notice in the past, that sometimes someone comes up with a great idea or new knowledge, and that Garry immediately adds it in his posts.
This time, I have plagiarized him. In fact, he told me about a study by Sergey e.a. which shows that big princess-cuts have more light return than big rounds. Garry can explain better which kind of light return. After all, I only stole the summary, he probably has all the info.
Live long,
18mm!!Date: 1/10/2006 8:08:12 PM
Author: Garry H (Cut Nut)
But note the ETAS for the very big princess!! (although we know the same diameter princess is 1/2 as heavy again as a round).
Date: 1/10/2006 8:28:35 PM
Author: Garry H (Cut Nut)
Emerald cut is about 100 times harder than square emerald cut.
(can anyone actually work it out? - I think it 8 to the power of 8 for square emerald and then that # to the power of 4 - but what would I know?)
I have no official or unofficial news as which will be the next AGS-shape. We are basically betting on the square emerald, because of multiple reasons:Date: 1/10/2006 8:09:34 PM
Author: Wink
This I do not know for sure, but it would make sense that since they had to do the work that they will release them both at the same time. Perhaps Paul knows...
Wink
Date: 1/11/2006 9:32:11 AM
Author: Paul-Antwerp
Date: 1/10/2006 8:09:34 PM
it is only logical that we are now preparing ourselves to cut square emeralds with high light performance, so that they can soon get the AGS 0-grade.
Live long,