- Joined
- Sep 3, 2000
- Messages
- 6,745
Here we have a graphic depicting a perfect color grade at the place where the letter "A" sits on the graph.
In the upper right we have a set of dots that is not accurate as it is not near point A and also looks like a shotgun blast, so it is also inconsistent.
In the lower right we have another not accurate grade, but there is a tightness of the points showing it is consistent.
Surrounding A we have another shotgun blast of points which are inconsistent, but have accuracy (in the overall).
Tightly surrounding the perfect color grade A, we have points that are accurate AND consistent.
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The GIA approach using only human grading is the shotgun blast surrounding loosely around the letter A. Its the best human graders, especially a large group of them, can be expected to do.
The tighter grouping which is accurate and consistent is what adding an expert system to color grading can accomplish. It will be an improved system although humans graders may find it painful to adapt to in the short run. In the long run, we'll all be better off with such systems in place.
This change in grading accuracy is taking place although it is not yet widely known. It is the beginning of a higher standard of operation for manufacturers and gem labs.
I thought there would be some folks who would like a visual and have a better handle on the proper use of the terminology.
In the upper right we have a set of dots that is not accurate as it is not near point A and also looks like a shotgun blast, so it is also inconsistent.
In the lower right we have another not accurate grade, but there is a tightness of the points showing it is consistent.
Surrounding A we have another shotgun blast of points which are inconsistent, but have accuracy (in the overall).
Tightly surrounding the perfect color grade A, we have points that are accurate AND consistent.
xxxxxxxxxxxxxxxxxxxx
The GIA approach using only human grading is the shotgun blast surrounding loosely around the letter A. Its the best human graders, especially a large group of them, can be expected to do.
The tighter grouping which is accurate and consistent is what adding an expert system to color grading can accomplish. It will be an improved system although humans graders may find it painful to adapt to in the short run. In the long run, we'll all be better off with such systems in place.
This change in grading accuracy is taking place although it is not yet widely known. It is the beginning of a higher standard of operation for manufacturers and gem labs.
I thought there would be some folks who would like a visual and have a better handle on the proper use of the terminology.
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