asscher question

[starryeyed]

According to WF, the image above is simulated from DiamCalc. They will have an actual image later. Any thoughts on all of the blue?

Here's an explanation from www.ideal-scope.com:

ASET shows where a diamond gathers its light.

Blue is blocked by the observer (some blue adds contrast)
Red is best: most light comes from above –from the ceiling
Green is OK; it is reflected and from windows, but red is better
White shows how much leakage is present (bad, especially when the leakage is adjacent to blue; when you will see a large dead dark zone in normal lighting)

UCLA, thanks for your comments. For those of you wanting more pictures of UCLA's GORGEOUS ring, here's the thread..

 

[kenny]

UCLA I definitely agree with you about the asscher size thing.

Last night I went to a concert at Disney Hall in Los Angeles.
I wanted to see my new 2.26 carat asscher in their lighting conditions.
There were lots of tiny bright lights in the very high ceiling of the lobby and the cafe.
While the asscher was dazzling my light-carat round ideal Solasfera next to it held its own very very well.

The asscher cost over 5 times as much but did not have 5 times the size or bling as that much smaller round.
If you want an asscher you really have to get the largest one possible, but then because of the cut you really don't want low clarity or color either.
Next a well-cut asscher apparently is like a needle in a haystack.

Rounds are definitely the way to go unless you can commit to a long arduous diamond safari and understand you must bump up your budget substantially to get an asscher of a size that compares to a round.

Rounds give you much more bling for the money.
But if you can find a good asscher is soooooooo worth it!

 

[starryeyed]

Here is the actual ASET image. I''d love to hear your ideas!

 

[strmrdr]

likley nice in person but not kicken.
Comparing the pic, IS, and ASET.
A lot of the angles are right on the border so it could look nice in person... But..
Id pass and hunt for a better one.

 

[Garry H (Cut Nut)]

Ok now we have some more info Storm i agree with you.

Before I was concerned that we had too little info for the judgement you made. The center of this stone is not gathering light from enough different directions.

Good people at White Flash - could I suggest you use the ASET with backlighting.

I find it next to useless when contrast is the issue (and it always is with fancy shapes- esp Asschers).

 

[starryeyed]

What effect does the backlighting have Garry? I take it the image would look different?

 

[Garry H (Cut Nut)]

(this is an proportion altered real stone)

Date: 12/4/2006 8:07:37 PM
Author: starryeyed
What effect does the backlighting have Garry? I take it the image would look different?

Note that in the top ASET with no backlight - you would think this stone would be quite good as it has alternating lighting pattenrs in the table ( a bit much blue - but it is just a quick fabricated example).

Note that in the bottom ASET with the back lighting turned on - we have a dark zone and a leakage zone side by side. That would show up as a very large easily seen dark zone and would be unattractive.

You would miss that when the ASET has no backlight.

 

[starryeyed]

Wow, that''s pretty cool. So perhaps I should ask for an ASET image with backlighting....These tools are so useful - thanks for helping with interpretation Garry!

 

[starryeyed]

I just realized that Asschers come in 3-step, 4-step, and 5-step cuts. Do the "ideal" depth and table percentages change based on how may steps there are?

What do you think of this one from James Allen? It''s a 5-step.

2.08 F VS1 66.8% 68% EX/VG

 

[strmrdr]

Date: 12/5/2006 4:08:18 PM
Author: starryeyed
I just realized that Asschers come in 3-step, 4-step, and 5-step cuts. Do the ''ideal'' depth and table percentages change based on how may steps there are?

What do you think of this one from James Allen? It''s a 5-step.

2.08 F VS1 66.8% 68% EX/VG

Dont like that one either...
bad angles in the culet area and its rather dark.
A good asscher under his lighting looks brighter.

 

[starryeyed]

Really, dark? In the culet or all over? Was the image brightened or something? It looked bright to me. Hmm....

 

[strmrdr]

http://www.jamesallen.com/diamond.asp?cid=131&item=860444
That one is worth getting better pictures of.

 

[strmrdr]

Date: 12/5/2006 4:46:49 PM
Author: starryeyed
Really, dark? In the culet or all over? Was the image brightened or something? It looked bright to me. Hmm....

run the magnifier over it and look at where you can see the background thru the stone and picture those areas dark.
That is why I like pictures of them over a dark background a lot better.
Back lighting and light backgrounds can cover up bad cutting in photos but in person it will stand out.

 

[strmrdr]

then do the same to the one I linked it has about 1/3 as much areas as the other and is tilted in the photo.
Which indicates its worth a better look but not enough to make a final decision.

 

[starryeyed]

Allow me to back-track for a moment - I am very interested in the JA's that you posted, but I'm, perplexed by this image. WF just sent it to me, it's the prior 2.47 F IF diamond - it looks like an image from a slight angle - the light reflection look huge. Any thoughts?

 

[strmrdr]

huge tilt no head shadow both of which makes asschers look brighter.
Doesn't tell you much about the face up appearance.
A totally dead asscher can be very bright at 20 degrees tilt.
A well cut asscher will also look brighter at angles.
Getting it right face up and so it will deal with head shadow is much harder.

https://www.pricescope.com/community/threads/asschers-and-aset-a-sneak-peek.35080/

Red is the area of brightest light return notice as the diamond is rotated the red increases for a good part of the rotation.

 

[strmrdr]

Date: 12/4/2006 12:52:34 PM
Author: kenny
UCLA I definitely agree with you about the asscher size thing.

Last night I went to a concert at Disney Hall in Los Angeles.
I wanted to see my new 2.26 carat asscher in their lighting conditions.
There were lots of tiny bright lights in the very high ceiling of the lobby and the cafe.
While the asscher was dazzling my light-carat round ideal Solasfera next to it held its own very very well.

The asscher cost over 5 times as much but did not have 5 times the size or bling as that much smaller round.
If you want an asscher you really have to get the largest one possible, but then because of the cut you really don''t want low clarity or color either.
Next a well-cut asscher apparently is like a needle in a haystack.

Rounds are definitely the way to go unless you can commit to a long arduous diamond safari and understand you must bump up your budget substantially to get an asscher of a size that compares to a round.

Rounds give you much more bling for the money.
But if you can find a good asscher is soooooooo worth it!

Repeat that test in candlelight and rotate the asscher back and forth :}
In bright spot lighting a well cut round will have better white light return than an asscher.

 

[starryeyed]

Wow, Storm. That was a pretty extensive ASET run. Tell me, does it matter how many steps - 3, 4 of 5?

 

[strmrdr]

Date: 12/5/2006 11:10:42 PM
Author: starryeyed
Wow, Storm. That was a pretty extensive ASET run. Tell me, does it matter how many steps - 3, 4 of 5?

no not really.
Its easier to get a multi-step/narrow-step pattern with more facets (physical steps vs optical steps) but 3 and 3 physical steps will do it just as well.
There are woofers out there will all different combos of facet counts and kicken asschers too.

 

[strmrdr]

Date: 12/5/2006 11:10:42 PM
Author: starryeyed
Wow, Storm. That was a pretty extensive ASET run. Tell me, does it matter how many steps - 3, 4 of 5?

Aso for the record those are simulated ASET images from a model I created when designing high a high performance asscher using DiamCalc.
DC has been used in this way to design many high performance cuts that have been brought to market.
It does it very very well.
Real world asschers with the same specs can be expected to perform the same way.
I have duplicated with helium scanner bases files to verify my models.

 

[kenny]

Strm
Okay I have a candle going.

What am I looking for?

BTW, mine is a 3-step.
I see three pavilion angles and three crown angles.

It would seem to me that a 3 step would have larger facets, but fewer, than a 4 step.
This would give larger flashes, but fewer of them than a 4 step.

 

[Garry H (Cut Nut)]

Date: 12/5/2006 11:10:42 PM
Author: starryeyed
Wow, Storm. That was a pretty extensive ASET run. Tell me, does it matter how many steps - 3, 4 of 5?

This is the reason i suggest people use ASET by hand and move the stones thru different orientations looking for bad features.

AGS use different orientations 0 thru 45 degrees in 45 1 degree steps and their software counts the pixels in each virtual image.

you can learn to do the same thing with a hand held ASET

 

[kenny]

Garry why are there 3 columns?

 

[Garry H (Cut Nut)]

Date: 12/5/2006 11:36:13 PM
Author: kenny
Garry why are there 3 rows?

from the left
ASET 30 degree blue
ASET 40 degree blue
Fire reverse ray trace

They also now use a fire forward ray trace too (hope i got them the right way around) Brighter colors = more potential for fire. i doubt that it is a proven system but better than nothing

 

[starryeyed]

Date: 12/5/2006 5:01:18 PM
Author: strmrdr

Date: 12/5/2006 4:46:49 PM

Author: starryeyed

Really, dark? In the culet or all over? Was the image brightened or something? It looked bright to me. Hmm....

run the magnifier over it and look at where you can see the background thru the stone and picture those areas dark.

That is why I like pictures of them over a dark background a lot better.

Back lighting and light backgrounds can cover up bad cutting in photos but in person it will stand out.

Wow Storm, you have a really sensitive eye. I have no idea what is gray from the facet vs gray from the background looking through the facet. The 2.08 F VS1 with 5 steps looked to me like it was reflecting a lot of light, but it sounds like perhaps the stone is glassy? I see more dark areas in the 2.01 G VS2 - this is a good thing? Hmmmm....

I think asschers over the internet is very difficult! I''m trying my best to learn what to look for, so thanks for your help!

 

[starryeyed]

Have a look at this one. It is a 2.35 F VS1. The vendor (great guy!) said that this stone was cut by one of the top asscher cutters - the company specializes in these and radiants. What do you think? Looks a little dark under the table (again), but I''m not an expert.

 

[momof3]

ok kenny, now you're freaking me out

i just purchased a 1.13 carat asscher, which is pretty deep (i think like 69% depth) - what will it "look" like in size compared to, say a princess???

it's 5.85x5.76x3.93

i just looked up some princess cuts same carat size w/ same depth and it's measurements were

5.83x5.559x3.88

my old stone was a princess, so will i have less size shock since i'm not comparing to rounds???

the setting has a halo, so that will help, but i don't want to be in for a shock!

 

[strmrdr]

Date: 12/6/2006 10:28:10 AM
Author: starryeyed
Have a look at this one. It is a 2.35 F VS1. The vendor (great guy!) said that this stone was cut by one of the top asscher cutters - the company specializes in these and radiants. What do you think? Looks a little dark under the table (again), but I''m not an expert.

Tough lighting/pic to read but your reading of it is right it looks to me.
Can you get an ASET image to make sure?

 

[starryeyed]

Hi Storm. I''m not sure if an ASET is available. In the meantime, I thought it would be interesting to post a Royal Asscher. Any thoughts? It''s a pretty glitzy photo...

 

[strmrdr]

Date: 12/6/2006 4:02:07 PM
Author: starryeyed
Hi Storm. I'm not sure if an ASET is available. In the meantime, I thought it would be interesting to post a Royal Asscher. Any thoughts? It's a pretty glitzy photo...

real real nice but expensive.
ie kicken