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 » RockyTalky
»  » Diamcalc - depth % still not based on average diameter?
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Diamcalc - depth % still not based on average diameter? |
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| P: 9/13/2007 12:23:01 AM | |
stebbo Cut Rock Total Posts: 466 Last Post: 1/27/2008 Member Since: 6/8/2006 |
Any idea why not?
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| Posted: 9/13/2007 12:23:01 AM | |
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There are 7 replies to this message. There are 7 replies on this page. |
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| P: 9/13/2007 1:12:46 AM | |
Serg Ideal Rock Total Posts: 1,514 Last Post: 11/23/2009 Member Since: 3/22/2002 |
Hi Stebbo, Do you know any reason( except Historical reasons ) Why for oval we should use min. diameter and for Round cut we should use average diameter? Sergey Sivovolenko |
| Posted: 9/13/2007 1:12:46 AM | |
| P: 9/13/2007 1:56:42 AM | |
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stebbo Cut Rock Total Posts: 466 Last Post: 1/27/2008 Member Since: 6/8/2006 |
Date: 9/13/2007 1:12:46 AM Author: Serg Hi Stebbo, Do you know any reason( except Historical reasons ) Why for oval we should use min. diameter and for Round cut we should use average diameter? Are you answering a question with a question?  How about because averages of broadly spread data are less practically meaningful than tightly spread data? But I understand your point.How about a right-click depth option?  In the rare instance that all parameters are locked except depth, the calculation from a depth % to 2 diameters could make the 2 diameters equal or preferably keep the current diameter ratio intact.
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| Posted: 9/13/2007 1:56:42 AM | |
| P: 9/13/2007 8:02:34 AM | |
oldminer Ideal Rock Total Posts: 4,964 Last Post: 11/20/2009 Member Since: 9/4/2000 |
Logical or not, depth percentage relates to the "width" measure of all fancy shapes per GIA guidelines. Only with rounds is the average used. There was one Branded diamond on the market, the name presently escapes me, that convinved the lab which did their grading to us a diagonal measurement as it was a square stone. This gave people a false less deep depth percentage and they were claiming it created a diamond that look larger than its princess cut competition. Purely smoke and mirrors, but made gemologists wonder where the depth % measure came from every time they saw that stone with its "special" cert. Since a diamond can have a rather straight pavilion from girdle to culet or in some cuts have a bulging pavilion with two pavilion angles, one higher and one lower, then depth percentage really means less on those buging ones. Of course, either pavilion angle alone means little, too. Again, it is a often a trick to game the existing system of reporting certain limited parameters in order to claim a particular diamond is better than another. Certain characterisitcs of cutting fancy shapes lead to parameters which can be played with much like painting and digging with rounds, but it is not limited to the girdle zone. David S. Atlas |
| Posted: 9/13/2007 8:02:34 AM | |
| P: 9/13/2007 8:21:43 AM | |
Garry H (Cut Nut) Ideal Rock Total Posts: 11,579 Last Post: 11/23/2009 Member Since: 8/16/2000 |
Stebbo what would you think of a diamond that was faceted out of 3 point rough? Te average LxW means nothing. They exist.  Garry Holloway FGAA DipDT |
| Posted: 9/13/2007 8:21:43 AM | |
| P: 9/13/2007 10:23:48 AM | |
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stebbo Cut Rock Total Posts: 466 Last Post: 1/27/2008 Member Since: 6/8/2006 |
Date: 9/13/2007 8:21:43 AM Author: Garry H (Cut Nut) Stebbo what would you think of a diamond that was faceted out of 3 point rough? With my knowledge of rough, I'd say that would be a very shallow diamond, in fact a depth of 0%, quite a lot of leakage. I realize that a min-max average can be misleading, and I agree that the defined 4-point Helium-type average is more representative, but DiamCalc likes to represent the AGS and GIA's girdle definitions, minor facet definitions, etc, it just seems weird it doesn't represent their depth % definition. Rather it's made generic with the other shapes which have their own uniqueness.
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| Posted: 9/13/2007 10:23:48 AM | |
| P: 9/13/2007 10:46:41 AM | |
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Serg Ideal Rock Total Posts: 1,514 Last Post: 11/23/2009 Member Since: 3/22/2002 |
Date: 9/13/2007 10:23:48 AM Author: stebbo Date: 9/13/2007 8:21:43 AM Author: Garry H (Cut Nut) Stebbo what would you think of a diamond that was faceted out of 3 point rough? With my knowledge of rough, I'd say that would be a very shallow diamond, in fact a depth of 0%, quite a lot of leakage. I realize that a min-max average can be misleading, and I agree that the defined 4-point Helium-type average is more representative, but DiamCalc likes to represent the AGS and GIA's girdle definitions, minor facet definitions, etc, it just seems weird it doesn't represent their depth % definition. Rather it's made generic with the other shapes which have their own uniqueness.
Sometimes we do both possibility( Reasonable and Standard. See lower girdle height) It will very misleading for DC clients too( DC is 10 old software ) We can do it only if anybody will give clear definition BOUNDARY between round cut and OVAL cut( How could we use average for round cut and minimum for oval cut, if we do not know where boundary is) :) There are easy do complex software with a lot of options. But I try develop RESONABLE software. Firstly FUN, then Comfort , then Profit Again we can easy give to options but I afraid it will increase misleading ƒ¼ Sergey Sivovolenko |
| Posted: 9/13/2007 10:46:41 AM | |
| P: 9/13/2007 11:35:56 AM | |
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stebbo Cut Rock Total Posts: 466 Last Post: 1/27/2008 Member Since: 6/8/2006 |
Date: 9/13/2007 10:46:41 AM Author: Serg We can do it only if anybody will give clear definition BOUNDARY between round cut and OVAL cut( How could we use average for round cut and minimum for oval cut, if we do not know where boundary is) :)
DiamCalc doesn't need to know where the boundary is, the user sets whether it's a round or an oval by selecting either round or oval from the standard shapes available. BTW: You don't develop REASONABLE software, you develop AMAZING software. It wouldn't seem like an anomaly if the sofware was only reasonable.
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| Posted: 9/13/2007 11:35:56 AM | |
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