What is the "black" in an idealscope img?

[denverboy]

ok i tried doing a search but couldnt find an answer (maybe i wasn't searching well hmm)

what is the black color in an idealscope img represent? for example, the arrows in a H&A idealscope.
I know white is leakage and red is light return... but I didn't see the black explained anywhere unless i was overlooking something.

and even in real color photos obviously the arrows are black, as if there is no white light return going on in that portion of the stone. So in one way i'm thinking .. are those like little arrows of shadow or no light? wouldn't a stone w/o these arrows look "whiter"? I know this reasoning is wrong but can someone clarify why exactly.

 

[Ellen]

Here's a couple links that should answer your question.

https://www.pricescope.com/community/threads/why-we-prefer-aset-to-ideal-scope-with-fancy-shapes.73949/

http://goodoldgold.com/Technologies/ReflectorTechnologies/History/

 

[Rhino]

Hi denver,

Date: 9/9/2008 8:14:48 PM
Author:denverboy
ok i tried doing a search but couldnt find an answer (maybe i wasn''t searching well hmm)

what is the black color in an idealscope img represent? for example, the arrows in a H&A idealscope.
I know white is leakage and red is light return... but I didn''t see the black explained anywhere unless i was overlooking something.

In the photography you commonly see it is specifically a reflection of the camera lens being reflected into the pavilion mains (and other facets, like through the stars). These amount of black reflections can change or be altered by either the size of the aperature of the red reflector being used, the length of the lower girdle facets, the actual angle of the pavilion main facets or all of the above. I have seen examples of the same diamond taken under various reflectors and the image changing from one photograph to the other. Sometimes so notably different that you''d never think it was the same diamond.

and even in real color photos obviously the arrows are black, as if there is no white light return going on in that portion of the stone. So in one way i''m thinking .. are those like little arrows of shadow or no light? wouldn''t a stone w/o these arrows look ''whiter''? I know this reasoning is wrong but can someone clarify why exactly.

This is a very good question denver and one that is not easily answered with reflector based technology (IS, Dxray, ASET, etc.) and your reasoning is by no means wrong.

The "dark arrows" you see in photography is a reflection of camera lens similar to the reflection of the lens you see in red reflector images. So the answer to your question "are those like little arrows of shadow or no light?" ... The answer is both. It is arrows of shadow and in those photographs no light.

It is supposed to be representative of "head/body" shadow in AGS'' system but the fact of the matter is true to life head/body shadow does not show up like it does in the photography you commonly see.

Even in the realm of precision cut H&A''s there are those that reflect back more shadow than others (even if slightly) due to varying pavilion angles. Noting a point you bring up ... 2 diamonds can have virtually identical reflector images yet the pavilion mains in one H&A can be on the darker side and one can have the pavilion mains illuminating more frequently. Two slightly different flavors of H&A due to pavilion angles. One places a tad more emphasis on contrast while the other a tad more emphasis on brightness. I''ve studied this exact phenomena you''re talking about and have also captured the visible differences between the two variations in some of the vids I''ve published. Your thinking is not off base at all. In fact the latter would be produced by pavilion angles around the 41.0/41.1 degree range in precision cut H&A''s and I happen to like them very much as they are spectacular and no less beautiful than 40.7-40.8 degree pavilion angles!

Peace,

 

[Garry H (Cut Nut)]

In addition to Rhino''s explanation i will try to make it easier

Date: 9/9/2008 8:14:48 PM
Author:denverboy
ok i tried doing a search but couldnt find an answer (maybe i wasn''t searching well hmm)

what is the black color in an idealscope img represent? for example, the arrows in a H&A idealscope.
I know white is leakage and red is light return... but I didn''t see the black explained anywhere unless i was overlooking something.
http://www.ideal-scope.com/light_return_and_shadow.asp there is an explanation here

and even in real color photos obviously the arrows are black, as if there is no white light return going on in that portion of the stone. So in one way i''m thinking .. are those like little arrows of shadow or no light? wouldn''t a stone w/o these arrows look ''whiter''? I know this reasoning is wrong but can someone clarify why exactly.
If you rock a well cut round diamond slightly away from you you will note some of the stars go from black to very bright very quickly. It depends on the light of course - but you can see it easily.

Finally the white arrows thru H&A''s scope are white because the inside of the scope has a white reflector for high almost perpendicualr light return.

(Always remember that there is almost always some leakage and that can explain why the black is somethmes grey)

 

[Ellen]

Date: 9/9/2008 9:08:56 PM
Author: Rhino
Even in the realm of precision cut H&A's there are those that reflect back more shadow than others (even if slightly) due to varying pavilion angles. Noting a point you bring up ... 2 diamonds can have virtually identical reflector images yet the pavilion mains in one H&A can be on the darker side and one can have the pavilion mains illuminating more frequently. Two slightly different flavors of H&A due to pavilion angles. One places a tad more emphasis on contrast while the other a tad more emphasis on brightness. I've studied this exact phenomena you're talking about and have also captured the visible differences between the two variations in some of the vids I've published. Your thinking is not off base at all. In fact the latter would be produced by pavilion angles around the 41.0/41.1 degree range in precision cut H&A's and I happen to like them very much as they are spectacular and no less beautiful than 40.7-40.8 degree pavilion angles!

Peace,

Yep. My diamonds arrows never appear black, just a beautiful silver.