Using IS--how should a CZ look?

[Picabia]

I bought an ideal scope without the pocket light and I''m trying to figure out how to use it. I bought a practice CZ to get the hang of it. Any idea what a CZ is supposed to look like under the IS?

 

[yssie]

http://www.ideal-scope.com/1.using_reference_chart.asp

 

[stone-cold11]

The practice CZ is cut to the proportion that would give it similar light return as a diamond RB.

 

[Garry H (Cut Nut)]

Date: 5/7/2010 4:47:14 PM
Author:Picabia
I bought an ideal scope without the pocket light and I''m trying to figure out how to use it. I bought a practice CZ to get the hang of it. Any idea what a CZ is supposed to look like under the IS?

This 40 second video
http://www.youtube.com/watch?v=6SfK5Nt3oXw&feature=channel
shows what you will see. You can take your own photo very easily and post it if you like?

And this shows what a very very bad stone looks like:
http://www.youtube.com/watch?v=h_yqYDZdxyI&NR=1

 

[Picabia]

Thanks everyone. Sorry my question was vague. I do have all the links to the various IS tutorials. I just wasn''t sure if CZs look substantially different under the scope. I was under the impression that diamonds refracted light uniquely and didn''t want to practice with a CZ and then not know how to compare that to a diamond.

I took some pictures through the scope (with a camera phone, sorry). Maybe someone can tell me if it looks like I''m doing this correctly? Since I didn''t buy the pocket light (which I should have) I had to make my own light. It''s a flashlight with a few sheets of paper over the LED bulbs and a hole to rest the diamond. Think this will work? My only concern is that the hole where the stone sits is brighter than the rest of the light.

So if I''m doing this right, the CZ in the pictures is a good cut, correct?
Thanks!

 

[Picabia]

Another view

 

[Picabia]

My Macgyver light

 

[stone-cold11]

I think the CZ is not totally level with the idealscope from the image.

Do you have a clear hard plastic that you can placed over the scope with the eye-piece on the table?

Try resting the camera on the table, lens up. Place the scope on the lens, clear plastic on the scope and the diamond/CZ on the plastic.

 

[Picabia]

Thanks stone-cold.
I gave it a shot and used a cd cover with the scope upside down. The stone still looks very pink. This would be an extremely ideal cut, correct? Hopefully I can figure this out before I get to NYC Monday...

For anyone who knows, I''m still curious about the difference in light refraction between a CZ and a diamond. I was under the impression that light bounces around a lot more in a diamond, so shouldn''t a CZ always look bad under an IS? Or am I mistaken?

 

[yssie]

Date: 5/8/2010 10:26:43 PM
Author: Picabia
Thanks stone-cold.
I gave it a shot and used a cd cover with the scope upside down. The stone still looks very pink. This would be an extremely ideal cut, correct? Hopefully I can figure this out before I get to NYC Monday...

For anyone who knows, I'm still curious about the difference in light refraction between a CZ and a diamond. I was under the impression that light bounces around a lot more in a diamond, so shouldn't a CZ always look bad under an IS? Or am I mistaken?

Why?


Link to what the IS actually is, and how it works: https://www.pricescope.com/idealscope_indx.asp


If light is going to be returned from the table/crown facets the IS will show it, regardless of reflections or refractions into or within the stone itself. The IS shows what is outputted through these top facets and implies nothing about anything else.

 

[kenny]

Date: 5/8/2010 10:26:43 PM
Author: Picabia
For anyone who knows, I'm still curious about the difference in light refraction between a CZ and a diamond.
I was under the impression that light bounces around a lot more in a diamond, so shouldn't a CZ always look bad under an IS?
Or am I mistaken?

Light travels in a straight line but bends (changes direction slightly) when it passes between things, such as between air and water, air and diamond or air and CZ.
Each of these substances have different properties which cause the light to bend different amounts.
The amount a substance bends light is described by Index of Refraction.

Diamond and CZ do not have the same index of refraction so to get a CZ to redirect light back up to the crown and perform and look like like a well-cut diamond the angles and proportions of the CZ must be different than those of a diamond.

So it is possible for both a CZ and a diamond to be cut so they will perform similarly under the Idealscope.
BTW, FWIW, I bought these two CZs from Garry Holloway, one is well-cut and the other is poorly-cut. Link

 

[Garry H (Cut Nut)]

You have the photo''s right - if that is what you see then you are on target.
The CZ has a bigger table and deeper pavilion to achieve a good cut, so a diamond will / might not look exactly the same.\
Light does bounce around more in diamond - RI 2.418 vs CZ 2.174. The lower the RI the more ''glassy'' or see thru the material.