Dark vs. Light Arrows . . .

[the tree sees]

Hello all,

I discovered this site a months ago and have been hooked ever since. Thanks for all the informative posts, particularly to regulars like Lorelei, Stone Cold, & Ellen! You are a truly appreciated wealth of information.

I have a question about the optical characteristics of different stones. Obviously each diamond has its own personality, but something that''s really noticeable is the different appearances of "arrows" in the 40X magnifications. For example, in some images the arrows can be rather dark...

Example

Or sometimes they can be really light on the inside or out (or in alternating patterns)...

Example

Do these differences in appearance speak to the optical quality of a diamond, or do consumers have different preferences as to these characteristics?

 

[Moh 10]

In t his case it may be just the color of whatever surface the diamond is reflecting.

 

[stone-cold11]

nay, just photographic artifacts, nothing to worry about.

 

[the tree sees]

Oh, okay, that makes sense. I thought it was weird whenever I pulled up a pic of a diamond with arrows that alternated in "color":

Example

Sort of a cool effect, actually! What about the size of the arrows, though? They can often be sharper or thicker--that must be a function of cut, no?

 

[Lorelei]

Date: 6/13/2009 12:54:53 PM
Author: the tree sees
Oh, okay, that makes sense. I thought it was weird whenever I pulled up a pic of a diamond with arrows that alternated in 'color':

Example

Sort of a cool effect, actually! What about the size of the arrows, though? They can often be sharper or thicker--that must be a function of cut, no?

Arrow thickness is down to the lower girdle facet size, this page explains further and should give you the info you need.

https://www.pricescope.com/community/threads/how-significant-are-the-star-facets-and-lower-girdles-info.31985/

Dark arrows are often seen in photography due to the light making them contrast, in reality they look more silvery usually.

 

[the tree sees]

Wow, great thread. Thanks for bumping it up for me, Lorelei.

 

[Lorelei]

Date: 6/13/2009 1:22:28 PM
Author: the tree sees
Wow, great thread. Thanks for bumping it up for me, Lorelei.

Glad to help Jason! Just shout if you need any more info, I have access to hundreds of great articles and threads I have collected over my years here!

 

[stone-cold11]

Lorelei, that thread should be link under in the useful thread link, very useful.

 

[Lorelei]

Date: 6/13/2009 1:38:58 PM
Author: Stone-cold11
Lorelei, that thread should be link under in the useful thread link, very useful.

Good point SC, thanks!

* goes to add it*

 

[Ellen]

tts, thank you so much for the shout out!

Actually, someone else asked the very same thing about GOG''s "light" and "dark" arrows not all that long ago, but I can''t fnd the thread. As I recall, the pavilion angles had something to do with it. Deeper vs. less deep. I will keep looking, and if I can''t find it, I''ll ask Jon to answer again for us.

 

[Ellen]

I see Jon is on, maybe he will catch this! Yoohoo, Rhinooooooo.

 

[Rhino]

Sorry for the late reply.

In brief ... the "arrows" or pavilion mains are reflecting back the lens of the camera in front of it. It looks akin to the blues in our ASET images and blacks via DiamXray imagery. When the diamond is aligned perfectly in front of the lens also gives a view to craftsmanship which our photos are designed to emphasize. In these photos of H&A diamonds, if you compare pavilion angle data you''ll generally find that those H&A diamonds that are cut with pavilion angles around the 40.6-40.8 zone will show the darker arrows and those with 40.9-41.0 angles are showing the lighter arrows. This is due to the fact that when you make the pavilion angles slightly steeper (40.9-41) those facets stand a better chance of grabbing light from around the viewer as opposed to drawing the shadow of the observer before the diamond.

I have captured this phenomena and what this looks like IRL via some of the video comparison''s I''ve shot in the past as some H&A''s appear a bit more contrasty with the arrows going darker vs the arrows lighting up. Two slightly varying appearances amongst the GIA Ex/AGS Ideal zenith zone.

 

[Ryon]

Date: 6/16/2009 3:24:40 PM
Author: Rhino
Sorry for the late reply.

In brief ... the ''arrows'' or pavilion mains are reflecting back the lens of the camera in front of it. It looks akin to the blues in our ASET images and blacks via DiamXray imagery. When the diamond is aligned perfectly in front of the lens also gives a view to craftsmanship which our photos are designed to emphasize. In these photos of H&A diamonds, if you compare pavilion angle data you''ll generally find that those H&A diamonds that are cut with pavilion angles around the 40.6-40.8 zone will show the darker arrows and those with 40.9-41.0 angles are showing the lighter arrows. This is due to the fact that when you make the pavilion angles slightly steeper (40.9-41) those facets stand a better chance of grabbing light from around the viewer as opposed to drawing the shadow of the observer before the diamond.

I have captured this phenomena and what this looks like IRL via some of the video comparison''s I''ve shot in the past as some H&A''s appear a bit more contrasty with the arrows going darker vs the arrows lighting up. Two slightly varying appearances amongst the GIA Ex/AGS Ideal zenith zone.

Wow thanks for all of the information!
Mine coming in is a 41.0 I will get light arrows.
Which do you honestly prefer? I bet they are both amazing in their own right.

 

[Ellen]

Hi Ryon,

Actually, this is just a pictorial phenomenom. In real life, your arrows most likely won't ever be dark, usually they show up silvery (very pretty), but some crown/pavilion angles can cause the arrows to appear dark at times.

 

[Rhino]

Date: 6/16/2009 7:42:55 PM
Author: Ryon

Date: 6/16/2009 3:24:40 PM

Author: Rhino

Sorry for the late reply.


In brief ... the ''arrows'' or pavilion mains are reflecting back the lens of the camera in front of it. It looks akin to the blues in our ASET images and blacks via DiamXray imagery. When the diamond is aligned perfectly in front of the lens also gives a view to craftsmanship which our photos are designed to emphasize. In these photos of H&A diamonds, if you compare pavilion angle data you''ll generally find that those H&A diamonds that are cut with pavilion angles around the 40.6-40.8 zone will show the darker arrows and those with 40.9-41.0 angles are showing the lighter arrows. This is due to the fact that when you make the pavilion angles slightly steeper (40.9-41) those facets stand a better chance of grabbing light from around the viewer as opposed to drawing the shadow of the observer before the diamond.


I have captured this phenomena and what this looks like IRL via some of the video comparison''s I''ve shot in the past as some H&A''s appear a bit more contrasty with the arrows going darker vs the arrows lighting up. Two slightly varying appearances amongst the GIA Ex/AGS Ideal zenith zone.

Wow thanks for all of the information!

Mine coming in is a 41.0 I will get light arrows.

Which do you honestly prefer? I bet they are both amazing in their own right.

You are right. They are both amazing in their own right and in many lighting environments would be difficult to distinguish. It is more notable at the extremes (40.6 vs 41.0). I almost hate to give my preference because people would interpret it as being the *best* when my personal preference may in fact differ from another''s. My findings on "personal preference" also factors an individuals'' focal length as younger people generally have a shorter focal length and older folks a longer focal length.

Let me just say this ... Diamonds with superior optical symmetry that have 41.0 pavilion angles are amongst the most beautiful diamonds this experts eye have ever laid eyes on and I have seen virtually every variety of super ideal to be observed.

 

[Ryon]

Date: 6/16/2009 11:22:20 PM
Author: Rhino

Date: 6/16/2009 7:42:55 PM
Author: Ryon

Date: 6/16/2009 3:24:40 PM

Author: Rhino

Sorry for the late reply.


In brief ... the ''arrows'' or pavilion mains are reflecting back the lens of the camera in front of it. It looks akin to the blues in our ASET images and blacks via DiamXray imagery. When the diamond is aligned perfectly in front of the lens also gives a view to craftsmanship which our photos are designed to emphasize. In these photos of H&A diamonds, if you compare pavilion angle data you''ll generally find that those H&A diamonds that are cut with pavilion angles around the 40.6-40.8 zone will show the darker arrows and those with 40.9-41.0 angles are showing the lighter arrows. This is due to the fact that when you make the pavilion angles slightly steeper (40.9-41) those facets stand a better chance of grabbing light from around the viewer as opposed to drawing the shadow of the observer before the diamond.


I have captured this phenomena and what this looks like IRL via some of the video comparison''s I''ve shot in the past as some H&A''s appear a bit more contrasty with the arrows going darker vs the arrows lighting up. Two slightly varying appearances amongst the GIA Ex/AGS Ideal zenith zone.

Wow thanks for all of the information!

Mine coming in is a 41.0 I will get light arrows.

Which do you honestly prefer? I bet they are both amazing in their own right.

You are right. They are both amazing in their own right and in many lighting environments would be difficult to distinguish. It is more notable at the extremes (40.6 vs 41.0). I almost hate to give my preference because people would interpret it as being the *best* when my personal preference may in fact differ from another''s. My findings on ''personal preference'' also factors an individuals'' focal length as younger people generally have a shorter focal length and older folks a longer focal length.

Let me just say this ... Diamonds with superior optical symmetry that have 41.0 pavilion angles are amongst the most beautiful diamonds this experts eye have ever laid eyes on and I have seen virtually every variety of super ideal to be observed.

Thanks Ellen and John
First off I never thought I would be talking to the owner of GOG

I see your point, because if you pick one over the other, then you might loose buisness on some amazing stones for no reason. I feel good about my incoming diamond now that you aprove
Also I never even thought about focal lengths, but you have a really great point on that also. For the most part diamonds really do come down to personal preference.

Ellen- thanks, for making that clear

 

[Lula]

Date: 6/19/2009 8:48:30 AM
Author: Ryon

Date: 6/16/2009 11:22:20 PM
Author: Rhino

Date: 6/16/2009 7:42:55 PM
Author: Ryon

Date: 6/16/2009 3:24:40 PM

Author: Rhino

Sorry for the late reply.


In brief ... the ''arrows'' or pavilion mains are reflecting back the lens of the camera in front of it. It looks akin to the blues in our ASET images and blacks via DiamXray imagery. When the diamond is aligned perfectly in front of the lens also gives a view to craftsmanship which our photos are designed to emphasize. In these photos of H&A diamonds, if you compare pavilion angle data you''ll generally find that those H&A diamonds that are cut with pavilion angles around the 40.6-40.8 zone will show the darker arrows and those with 40.9-41.0 angles are showing the lighter arrows. This is due to the fact that when you make the pavilion angles slightly steeper (40.9-41) those facets stand a better chance of grabbing light from around the viewer as opposed to drawing the shadow of the observer before the diamond.


I have captured this phenomena and what this looks like IRL via some of the video comparison''s I''ve shot in the past as some H&A''s appear a bit more contrasty with the arrows going darker vs the arrows lighting up. Two slightly varying appearances amongst the GIA Ex/AGS Ideal zenith zone.

Wow thanks for all of the information!

Mine coming in is a 41.0 I will get light arrows.

Which do you honestly prefer? I bet they are both amazing in their own right.

You are right. They are both amazing in their own right and in many lighting environments would be difficult to distinguish. It is more notable at the extremes (40.6 vs 41.0). I almost hate to give my preference because people would interpret it as being the *best* when my personal preference may in fact differ from another''s. My findings on ''personal preference'' also factors an individuals'' focal length as younger people generally have a shorter focal length and older folks a longer focal length.

Let me just say this ... Diamonds with superior optical symmetry that have 41.0 pavilion angles are amongst the most beautiful diamonds this experts eye have ever laid eyes on and I have seen virtually every variety of super ideal to be observed.

Thanks Ellen and John
First off I never thought I would be talking to the owner of GOG

I see your point, because if you pick one over the other, then you might loose buisness on some amazing stones for no reason. I feel good about my incoming diamond now that you aprove
Also I never even thought about focal lengths, but you have a really great point on that also. For the most part diamonds really do come down to personal preference.

Ellen- thanks, for making that clear

LOL about your comment about talking to the owner of GOG! I''m a newbie, too, and I still get a thrill whenever Jonathan or one of the other vendors/experts posts on one of my threads!

 

[the tree sees]

Me too!

 

[bright&shiny]

Me three!

Jonathan,
Does the 41 degree angle apply only to RBs? What about the pavilion on an Asscher? I know the form is completely different, but even though the width and number of steps are variable, I have been wondering about the angle of the steps - and if it results in an overall pavilion angle - and thus and ideal....

 

[strmrdr]

Date: 6/19/2009 3:58:10 PM
Author: bright&shiny
Me three!


Jonathan,

Does the 41 degree angle apply only to RBs? What about the pavilion on an Asscher? I know the form is completely different, but even though the width and number of steps are variable, I have been wondering about the angle of the steps - and if it results in an overall pavilion angle - and thus and ideal....

asschers work in a different way than RB''s
While the angles determine where it draws light from it is much more complicated than with rounds.

Also the arrows changing color at ~41 degrees is specific to Jon''s lighting setup.
If you look at the Arrow, IS and ASET images the arrow color does not change.

 

[bright&shiny]

Date: 6/19/2009 4:35:00 PM
Author: strmrdr

Date: 6/19/2009 3:58:10 PM

Author: bright&shiny

Me three!



Jonathan,


Does the 41 degree angle apply only to RBs? What about the pavilion on an Asscher? I know the form is completely different, but even though the width and number of steps are variable, I have been wondering about the angle of the steps - and if it results in an overall pavilion angle - and thus and ideal....

asschers work in a different way than RB''s

While the angles determine where it draws light from it is much more complicated than with rounds.


Also the arrows changing color at ~41 degrees is specific to Jon''s lighting setup.

If you look at the Arrow, IS and ASET images the arrow color does not change.

Karl,

That, of course (now that you say it) makes sense. Perhaps that''s why I like Asschers More complex. Your comment about the other images remaining the same also makes sense to me now that you point it out....I guess this is just like real life - sometimes you need someone else to point out the obvious

Thank you for the information!

 

[strmrdr]

Your welcome bright&shiny.
Kewl user name btw.

 

[Rhino]

Yep. Karl is right on in his commentary. Every single time in every single instance it always boils down to the delicate balance between the relationship of both the crown and pavilion angles. What makes it more complicated with Assher''s is that you have 3 crown angles and generally 3 pavilion angle relationships that need to be analzyed which is done much better with reflectors but nothing beats an observation test alongside *known* winners because even reflectors can at times be misleading. Once we nail OEC''s, Assher''s are another project we are considering and I already have the formula.