Could all Infinity I1 clarity diamonds have High light performance?
- Thread starter Serg
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very bright Photos could camouflage some type I1 clarity( semi-transference crack) .
BTW
re:
'First, there is the problem that during most of 2008, AGS was extremely strict in their clarity-grading, and a lot of stones that they now would grade SI2 was graded I1 in that period. Other cutters most probably have sent these stones to GIA in order to get the SI2-grade, but we have stuck with our choice of lab. Today, also AGS will grade a high number of our I1's of last year as SI2.'
https://www.pricescope.com/community/threads/infinity-diamonds-i1.107412/
is AGS Grade for below Infinity I1 diamonds exctremely strict ?
[ Admin - the following link have been edited to point to the main source. The link contains the exact information ]
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5014&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5295&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5438&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5492&pid=63
BTW
re:
'First, there is the problem that during most of 2008, AGS was extremely strict in their clarity-grading, and a lot of stones that they now would grade SI2 was graded I1 in that period. Other cutters most probably have sent these stones to GIA in order to get the SI2-grade, but we have stuck with our choice of lab. Today, also AGS will grade a high number of our I1's of last year as SI2.'
https://www.pricescope.com/community/threads/infinity-diamonds-i1.107412/
is AGS Grade for below Infinity I1 diamonds exctremely strict ?
[ Admin - the following link have been edited to point to the main source. The link contains the exact information ]
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5014&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5295&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5438&pid=63
http://www.craftedbyinfinity.com/index.php?shapes=3&shapes=2&ref=5492&pid=63
Regular Guy
Ideal_Rock
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Serg,
It seems to me the relationships between inclusions, and their effect on light performance, have been talked about with ranges of opinion on the ones effect on the other, for some time. I went looking for such posts, found one I was looking for, and then found another I''m glad I stumbled into again.
For the first, comments from Paul, on the effects from inclusions...and the circumstances that govern their possible effects:
"Take the extreme case of an I2, and consider how much of the surface area would be touched by the inclusion. Of course, it is difficult to measure, and it depends upon the stone, but my guess would be maximum 5%.
I think that even in this clarity, a better cut-quality will still be giving a higher light performance.
So, therefore, in the case of an SI2, which I estimate will not even have an effect on 1% of the surface area of the stone, cut-quality will clearly prevail."
Also, interestingly, is this other post from Bill Bray towards the end of this 2 page thread dedicated to the topic:
"One of the difficulties of making the correlation between a diamond that performs well and a stone that is cut well is that there are other factors in addition to the quality of the cut that mitigate and in some instances totally negate this relationship. Some of these factors include but may not be limited to:
1. Color or opaqueness of color
2. Clarity
3. Material
4. Fineness of polish beyond just seeing “cutting lines”.
5. Granular structure and subsequent layout of the stone.
If my scoring system would take off there are ways to weight some of them in relationship to performance. For instance, a stone drawing slight color (i.e. I-J-K) would benefit in appearance from a varying degree of angles than say an Ideal cut. But we''re far from there.
Also, some of the items on that list, if they are taken to extremes, (Like the machine guys and my system are forced to do to incorporate error rates and their effect on the final outcome), then you can see that performance grading is only for better material. A badly knaated stone, a cloudy stone, an opague stone all perform much less than fine soft material.
All diamond is not the same."
This piece about "diamond material," like the quality of goods a clothing manufacturer might begin with....is like never addressed that I am aware of...and it would be good to hear some agreement or disagreement about the extent to which some of these other factors come into play, and might reasonably part of a consumer''s review of characteristic considerations.
It seems to me the relationships between inclusions, and their effect on light performance, have been talked about with ranges of opinion on the ones effect on the other, for some time. I went looking for such posts, found one I was looking for, and then found another I''m glad I stumbled into again.
For the first, comments from Paul, on the effects from inclusions...and the circumstances that govern their possible effects:
"Take the extreme case of an I2, and consider how much of the surface area would be touched by the inclusion. Of course, it is difficult to measure, and it depends upon the stone, but my guess would be maximum 5%.
I think that even in this clarity, a better cut-quality will still be giving a higher light performance.
So, therefore, in the case of an SI2, which I estimate will not even have an effect on 1% of the surface area of the stone, cut-quality will clearly prevail."
Also, interestingly, is this other post from Bill Bray towards the end of this 2 page thread dedicated to the topic:
"One of the difficulties of making the correlation between a diamond that performs well and a stone that is cut well is that there are other factors in addition to the quality of the cut that mitigate and in some instances totally negate this relationship. Some of these factors include but may not be limited to:
1. Color or opaqueness of color
2. Clarity
3. Material
4. Fineness of polish beyond just seeing “cutting lines”.
5. Granular structure and subsequent layout of the stone.
If my scoring system would take off there are ways to weight some of them in relationship to performance. For instance, a stone drawing slight color (i.e. I-J-K) would benefit in appearance from a varying degree of angles than say an Ideal cut. But we''re far from there.
Also, some of the items on that list, if they are taken to extremes, (Like the machine guys and my system are forced to do to incorporate error rates and their effect on the final outcome), then you can see that performance grading is only for better material. A badly knaated stone, a cloudy stone, an opague stone all perform much less than fine soft material.
All diamond is not the same."
This piece about "diamond material," like the quality of goods a clothing manufacturer might begin with....is like never addressed that I am aware of...and it would be good to hear some agreement or disagreement about the extent to which some of these other factors come into play, and might reasonably part of a consumer''s review of characteristic considerations.
Ira,
re:"Take the extreme case of an I2, and consider how much of the surface area would be touched by the inclusion. Of course, it is difficult to measure, and it depends upon the stone, but my guess would be maximum 5%.
1)I have not any Idea how Paul received just5% for I2
2) We need speak about how many facets and Light inclusions touch and destroy visually by inclusions
2) I think I1 destroy much more than 5% facets on Infinity photos had published above . Do you agree?
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strmrdr
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I believe there are many well cut I1 diamonds which absolutely outperform some less flawed stones which that are less well cut.
An I1 could outperform one with better clarity if the inclusions in the I1 were more transparent and/or better placed than ones in a higher clarity stone. While it might not happen often, I believe it well could happen. It is in the the nature of the inclusions, the transparency of individual stones, and many other details which have been touched upon. All have an effect on light return potential.
Relative to average cut diamonds, probably all of Infinity''s Ideal Cut ones are way better in measured performance with light. I sort of doubt Infinity would cut cloudy or dead due to inclusion type stones into their branded ideal cut. There would be little point in it for them and these diamonds would not only be hard to sell, but hurt the brand''s reputation.
An I1 could outperform one with better clarity if the inclusions in the I1 were more transparent and/or better placed than ones in a higher clarity stone. While it might not happen often, I believe it well could happen. It is in the the nature of the inclusions, the transparency of individual stones, and many other details which have been touched upon. All have an effect on light return potential.
Relative to average cut diamonds, probably all of Infinity''s Ideal Cut ones are way better in measured performance with light. I sort of doubt Infinity would cut cloudy or dead due to inclusion type stones into their branded ideal cut. There would be little point in it for them and these diamonds would not only be hard to sell, but hurt the brand''s reputation.
strmrdr
Super_Ideal_Rock
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When it was first discussed that here months ago that a PS vendor was pushing some high performance i1 diamonds my first thought was what a bunch of garbage based on the majority that I had seen.
Then I said wait a second I need to take another look because of the reputation of the vendor and cutter.
So I set out to find some to look at locally.
I found a lot of igi/egl/gia graded i1 diamonds locally.
Let me tell you the range of inclusions in them was huge even from the same lab!!!
From eyecleanish to a mess of carbon.
The cut quality ranged from absolutely awful to excellent range in ASET, IS, HCA scores and GIA scores.
The effects of the clarity on performance ranged from a disaster to none that was on the hand eye visible.
There was a pair of GIA EX/EX/EX from the same cutter one was a G/I1 and the other a G/vs2.
The numbers on the GIA report were virtually identical and they were within .04ct.
At close range about 6-8 inches the I1 had some slightly visible inclusions otherwise you could not tell them apart by eye under a variety of lighting.
There was an igi si1 in the same store that the inclusions had a much higher impact on the performance, a full third of the stone was dead.
So in the end the vendor did not receive the very sharply worded email that I first thought I was going to send.
The Pricescope poster ended up buying the diamond and loves it!
I have to agree with Paul/Wink/John an I1 diamond can be cut so that the inclusions have very little to no impact on performance.
I am 100% certain it can be brought down to a less than eye visible performance difference on the hand.
Personally instead of slamming people, investigating the art of minimizing the effect of inclusions and turning it into a science is a very worthy goal.
The bottom line:
Would I consider buying an I1 RB diamond? Certainly
Would I advise people to hunt for them? NO, because it is really a needle in a haystack.
Locally I only could find 1 or 2 that I found acceptable and most were very bad.
If a trusted vendor had one in stock would I recommend talking to the vendor about it? Yes I would.
Then I said wait a second I need to take another look because of the reputation of the vendor and cutter.
So I set out to find some to look at locally.
I found a lot of igi/egl/gia graded i1 diamonds locally.
Let me tell you the range of inclusions in them was huge even from the same lab!!!
From eyecleanish to a mess of carbon.
The cut quality ranged from absolutely awful to excellent range in ASET, IS, HCA scores and GIA scores.
The effects of the clarity on performance ranged from a disaster to none that was on the hand eye visible.
There was a pair of GIA EX/EX/EX from the same cutter one was a G/I1 and the other a G/vs2.
The numbers on the GIA report were virtually identical and they were within .04ct.
At close range about 6-8 inches the I1 had some slightly visible inclusions otherwise you could not tell them apart by eye under a variety of lighting.
There was an igi si1 in the same store that the inclusions had a much higher impact on the performance, a full third of the stone was dead.
So in the end the vendor did not receive the very sharply worded email that I first thought I was going to send.
The Pricescope poster ended up buying the diamond and loves it!
I have to agree with Paul/Wink/John an I1 diamond can be cut so that the inclusions have very little to no impact on performance.
I am 100% certain it can be brought down to a less than eye visible performance difference on the hand.
Personally instead of slamming people, investigating the art of minimizing the effect of inclusions and turning it into a science is a very worthy goal.
The bottom line:
Would I consider buying an I1 RB diamond? Certainly
Would I advise people to hunt for them? NO, because it is really a needle in a haystack.
Locally I only could find 1 or 2 that I found acceptable and most were very bad.
If a trusted vendor had one in stock would I recommend talking to the vendor about it? Yes I would.
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glitterata
Ideal_Rock
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strmrdr
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That is impossible to answer by looking at a picture.
I would talk to someone while they are looking at the stone then view it myself to decide.
That Paul has accepted it into the brand is a very good indication it isn''t much of an issue.
Lets for the sake of argument say there was a slight scientific reduction, the question becomes is it an eye visible difference in multiple lighting conditions?
Does the much lower cost on an i1 make up for it if it was?
Certainly it will be higher performance than a badly cut stone with the same inclusions.
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Hello Sergey and all.
Specific to Infinity the answer is absolutely.
Planning the diamond while it’s in the rough is key. Even so, any diamond we craft is simply a candidate through production. We evaluate every candidate at many stages as we craft it. Any failing to meet Paul’s standards simply won’t be branded. That spans all categories, not just clarity.
To address the specific diamonds asked-about:
The other examples are still in-stock. The mag-photos are not glamorous at this level of zoom in our setup, but the diamonds themselves have great performance. If not they would not have been included in the brand.
*
We fully admit we can improve our photos. It may be helpful to know why, as a manufacturer, we even started providing them. Many of our dealers sell in traditional stores and we thought data pages would be a nice supplement for them. Why? Because the only data given out in some traditional stores remains a business card with the diamond’s carat, color, clarity and price scribbled on the back! By providing these pages to our Infinity dealers, whether traditional or internet, they can give a link so clients can examine the diamond at their leisure when they get home. As far as I know we're the only manufacturer creating such pages for our dealer network. We may not be perfect but will continue to work to improve them.
When establishing the photos we tried to replicate leading internet retailers. At first we used an outside service. Eventually we brought the photography and scans in-house in order to improve them. We believe that has happened, especially in our reflector photos, but we can still get better. To that end we asked Garry Holloway to look at our process a couple of weeks ago when he was in our Antwerp offices. He gave us valuable input which we appreciate - it never hurts to sharpen the saw. No process it infallible however, especially at such a level of zoom. It may be a good idea to look at our mag-photos of I1 diamonds, specifically, to consider whether they hurt or help our efforts in cases.
Specific to Infinity the answer is absolutely.
Planning the diamond while it’s in the rough is key. Even so, any diamond we craft is simply a candidate through production. We evaluate every candidate at many stages as we craft it. Any failing to meet Paul’s standards simply won’t be branded. That spans all categories, not just clarity.
To address the specific diamonds asked-about:
(0.90 H I1 RB) I recall a question about the feather. It was already answered in the thread but you can bring up the grading report. All inclusions are red, indicating they’re internal.
(This is the diamond in the picture posted above - 1.29 H I1 RB). I agree that the zoomed photo looks terrible. This diamond likely never would have sold via the internet. It was sold live by an AGS-member jeweler who had other ideals alongside for comparison. For sure, the ‘net representation does not do it justice but it is a beautiful diamond. For the record, our jeweler also commented on how poor the photo is, compared to the live diamond. Mea culpa.
(1.15 G I1 RB) This diamond also sold in a traditional store - just one day after it arrived in the US from Antwerp. The jeweler is a former HOF seller with good knowledge and appreciation for cut. He has even made a standing request for Infinity I1s to be assigned to his store. We don’t produce a lot of them but when we do we find they are popular with our traditional retailers due, we believe, to the performance offered at that price point.
The other examples are still in-stock. The mag-photos are not glamorous at this level of zoom in our setup, but the diamonds themselves have great performance. If not they would not have been included in the brand.
*
We fully admit we can improve our photos. It may be helpful to know why, as a manufacturer, we even started providing them. Many of our dealers sell in traditional stores and we thought data pages would be a nice supplement for them. Why? Because the only data given out in some traditional stores remains a business card with the diamond’s carat, color, clarity and price scribbled on the back! By providing these pages to our Infinity dealers, whether traditional or internet, they can give a link so clients can examine the diamond at their leisure when they get home. As far as I know we're the only manufacturer creating such pages for our dealer network. We may not be perfect but will continue to work to improve them.
When establishing the photos we tried to replicate leading internet retailers. At first we used an outside service. Eventually we brought the photography and scans in-house in order to improve them. We believe that has happened, especially in our reflector photos, but we can still get better. To that end we asked Garry Holloway to look at our process a couple of weeks ago when he was in our Antwerp offices. He gave us valuable input which we appreciate - it never hurts to sharpen the saw. No process it infallible however, especially at such a level of zoom. It may be a good idea to look at our mag-photos of I1 diamonds, specifically, to consider whether they hurt or help our efforts in cases.
This is certain. It would be self-destructive to allow any Infinity to fall short of the standards we’ve worked hard to be known for - especially due to the following: There are only a few-hundred Infinity diamonds available at any time, shared between dealers. Our jeweler in St.Louis must be able to say “If you like the performance of the Infinity I showed you we can bring in another to fit your size and budget” - with total confidence in appeal & consistency. To that end we have great accountability to our professional clients as well as to consumer-buyers. We take our responsibilities to both groups very seriously.
strmrdr
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ok I looked up the ASET and IS images for that diamond.
I would say a case could be made for a slight scientific reduction in light return based on these images.
The question then becomes if it is eye visible and does the i1 price reduction cover it.
Neither of those questions can be answered by pictures.
Here they are:
I would say a case could be made for a slight scientific reduction in light return based on these images.
The question then becomes if it is eye visible and does the i1 price reduction cover it.
Neither of those questions can be answered by pictures.
Here they are:
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Nice and to the point strmrdr...
Date: 6/26/2009 4:13:57 PM
Author: strmrdr
When it was first discussed that here months ago that a PS vendor was pushing some high performance i1 diamonds my first thought was what a bunch of garbage based on the majority that I had seen.
Then I said wait a second I need to take another look because of the reputation of the vendor and cutter.
So I set out to find some to look at locally.
I found a lot of igi/egl/gia graded i1 diamonds locally.
Let me tell you the range of inclusions in them was huge even from the same lab!!! Yep..., not all I1''s are equal...
From eyecleanish to a mess of carbon.
The cut quality ranged from absolutely awful to excellent range in ASET, IS, HCA scores and GIA scores.
The effects of the clarity on performance ranged from a disaster to none that was on the hand eye visible.
There was a pair of GIA EX/EX/EX from the same cutter one was a G/I1 and the other a G/vs2.
The numbers on the GIA report were virtually identical and they were within .04ct.
At close range about 6-8 inches the I1 had some slightly visible inclusions otherwise you could not tell them apart by eye under a variety of lighting.
There was an igi si1 in the same store that the inclusions had a much higher impact on the performance, a full third of the stone was dead.
See..., to understand better, you must dig into the roots of the cutting system...
A lot of cutters I know personally will send an obvious I1 to a second tier lab for the purpose of an upgrade they would usually get. When the stone has a decent chance to get a genuine SI2..., the cutters will submit to GIA and hope for an SI2 but if it gets an I1..., chances its a decent I1 (that came with hopes for an SI2)
So in the end the vendor did not receive the very sharply worded email that I first thought I was going to send.
The Pricescope poster ended up buying the diamond and loves it!
I have to agree with Paul/Wink/John an I1 diamond can be cut so that the inclusions have very little to no impact on performance.
I am 100% certain it can be brought down to a less than eye visible performance difference on the hand.
Sure it can for two main reasons:
A) Knowlege on how to plan a rough Diamond as to partly-controlling the positions of inclusions is extremely effective and not practiced enough by big conglomerates (a big plus for boutique cutting houses).
B) When dealing with higher quality rough assortments on a regular basis..., the SI2''s and I1''s are the result of the lower end of that quality assortment... (eg- by the nature of the methods used to assort higher quality rough..., most often the SI2 or I1'' inclusions will be positioned much better to start with than a lower quality "pique" assortment.
I hope what I have written is understandable...
Personally instead of slamming people, investigating the art of minimizing the effect of inclusions and turning it into a science is a very worthy goal.
The bottom line:
Would I consider buying an I1 RB diamond? Certainly
Would I advise people to hunt for them? NO, because it is really a needle in a haystack.
Locally I only could find 1 or 2 that I found acceptable and most were very bad.
If a trusted vendor had one in stock would I recommend talking to the vendor about it? Yes I would.
strmrdr
Super_Ideal_Rock
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re:Neither of those questions can be answered by pictures.
in such case you can not use such pictures( ASET, IS) for Cut grade at all( for example to proof what diamond with small leakage as P41.2Cr35 has worse Light performance than Infinity diamonds)
re:The question then becomes if it is eye visible and does the i1 price reduction cover it.
I did not ask about price, I asked about Light Performance for House had been build on Light performance idea
But if you speak about price, please compare infinity I1 price with other well cutting I1 diamonds( without perfect symmetry)
I doubt what high level symmetry is helpfull to hide( reduce visibility) ANY I1 inclusions( I1 is big range)
Head obscuration is good to hide small inclusions ( VVS-SI), But
1) It is mainly for Photos. It work less for human stereo vision and does not work for Lab stereo Microscope at all
2) Cut can not change Rarity. Consumer can not see nether VVS nor VS, he does not pay premium for less visibility VS . He pays premium for Rarity
Cut light performance and Diamond light Performance are not same for bad color , big inclusions, milkiness..
sometimes diamonds better than Photo, sometimes Photo better than diamonds.
But
1) Infinity photos have Bloom what hide some small points at least
2) I1 Inclusions which has a lot of small points( I1 type) reduce LR, Fire... It is clear visible on Infinity photos and it will visible on real diamonds( if you compare with same cut with VS clarity)
strmrdr
Super_Ideal_Rock
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1) See image , A lot of virtual facets lost 5-30% LR due absorption and dispersion on inclusions
2) If you change P from 40.75 to 41,25 , less area will lost less than 10% LR
for me very interesting to see BrillianceScope and Imagem LR reports for this diamonds.
Real Brand should be ready proof Main Brand statements.
Sorry the "Any failing to meet Paul’s standards simply won’t be branded. " is not proof at all
Btw. Where Could consumer ( or I) read "Paul’s standards" and method to check diamond to accordance with the Standard ?
elle_chris
Ideal_Rock
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This is interesting as I''ve always wondered how much light return is lost in I1/I2 stones. From a physics perspective, what Serge is saying is true, there''s no way around it.
As Serge noted in that picture, "A lot of virtual facets lost 5-30% LR due absorption and dispersion on inclusions"
So can anyone cutting to precise H&A standards really say that their I clarity stones aren''t taking a hit for light return? I''m also wondering how eye visible this is when comparing the I1 to a smiliar cut VVS..
As Serge noted in that picture, "A lot of virtual facets lost 5-30% LR due absorption and dispersion on inclusions"
So can anyone cutting to precise H&A standards really say that their I clarity stones aren''t taking a hit for light return? I''m also wondering how eye visible this is when comparing the I1 to a smiliar cut VVS..
strmrdr
Super_Ideal_Rock
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strmrdr
Super_Ideal_Rock
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Real world impact in my experence can vary from practically none to a huge amount just in the GIA i1 range not counting i2 and other labs.
I do not agree with the 5% to 30%
A lot of them are impacted not at all and far more less than 1%.
I see 2-3 that I would consider more than 10% and they are on the upper girdles on the edge and a very small part of the diamond.
strmrdr
Super_Ideal_Rock
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http://en.wikipedia.org/wiki/Airy_disc#Cameras
In optics, the Airy disk (or Airy disc) and Airy pattern are descriptions of the best focused spot of light that a perfect lens with a circular aperture can make, limited by the diffraction of light.
The diffraction pattern resulting from a uniformly-illuminated circular aperture has a bright region in the center, known as the Airy disk which together with the series of concentric bright rings around is called the Airy pattern. Both are named after George Biddell Airy, who first described the phenomenon. The diameter of this pattern is related to the wavelength of the illuminating light and the size of the circular aperture.
The most important application of this concept is in cameras and telescopes. Due to diffraction, the smallest point to which one can focus a beam of light using a lens is the size of the Airy disk. Even if one were able to make a perfect lens, there is still a limit to the resolution of an image created by this lens. An optical system in which the resolution is no longer limited by imperfections in the lenses but only by diffraction is said to be diffraction limited.
Cameras
If two objects imaged by a camera are separated by an angle small enough that their Airy disks on the camera detector start overlapping, the objects can not be clearly separated any more in the image, and they start blurring together. Two objects are said to be just resolved when the maximum of the first Airy pattern falls on top of the first minimum of the second Airy pattern (the Rayleigh criterion).
Therefore the smallest angular separation two objects can have before they significantly blur together is given as stated above by
Thus, the ability of the system to resolve detail is limited by the ratio of ë/d. The larger the aperture for a given wavelength, the finer the detail which can be distinguished in the image.
Since è is small we can approximate this by
where x is the separation of the images of the two objects on the film and f is the distance from the lens to the film. If we take the distance from the lens to the film to be approximately equal to the focal length of the lens, we find
but is the f-number of a lens. A typical setting for use on an overcast day would be f/8.[1] For blue visible light, the wavelength ë is about 420 nanometers.[2] This gives a value for x of about 0.004 mm. In a digital camera, making the pixels of the image sensor smaller than this would not actually increase image resolution.
strmrdr
Super_Ideal_Rock
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Serg, I''m aware of that effect.
As we have discussed and mostly agree on. human vision also hides defects due to stereo vision by blurring them together and overlaying left eye right eye data.
We do disagree somewhat to what degree it happens and haven''t found a happy compromise point we both agree with yet.
We both agree it happens however.
As we have discussed and mostly agree on. human vision also hides defects due to stereo vision by blurring them together and overlaying left eye right eye data.
We do disagree somewhat to what degree it happens and haven''t found a happy compromise point we both agree with yet.
We both agree it happens however.
strmrdr
Super_Ideal_Rock
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Take any nice shot with fine professional camera. Then add dust ( a lot of dust ) on external surface perfect professional lens and take same shot.
You can not see any dust on second photo but quality second photo is worse than quality first photo.
Quality second photo is worse because optical system with dust has worse MTF
Of course less quality camera with same quantity of dust will give worse image. But less quality clean lens could easy give better image than high professional dirty lens
If you have not the shot from clean professional lens you can not understand what other images have some problem with quality.
Diamonds with I1 inclusion ( as a lot of small points spreading in all diamond( due internal reflections) like milkiness ) has worse MTF than clean diamonds with same geometry.
Even you do not see inclusions ( because each point is very small) , all these points together could noticeably reduce diamond MTF. Photos from lens with less MTF have worse sharpness and brightness than photos from lens with bigger MTF
Diamonds MTF depends from facet Flatness too. When cutters want receive good H&A pattern ( high level symmetry) they should use very good polishing disk( low vibration at least), what create better Flatness.
I think( my hypothesis ) what “true H&A“ diamonds have better light performance mainly because such diamonds have very good facet flatness ( better MTF). Parameters are important also of course, But flatness could be more important than high level symmetry .
Some tipe I1 inclusion reduce high score MTF had been created by fine facet flatness . So such diamonds can not have highest MTF and High Light Performance
You can not see any dust on second photo but quality second photo is worse than quality first photo.
Quality second photo is worse because optical system with dust has worse MTF
Of course less quality camera with same quantity of dust will give worse image. But less quality clean lens could easy give better image than high professional dirty lens
If you have not the shot from clean professional lens you can not understand what other images have some problem with quality.
Diamonds with I1 inclusion ( as a lot of small points spreading in all diamond( due internal reflections) like milkiness ) has worse MTF than clean diamonds with same geometry.
Even you do not see inclusions ( because each point is very small) , all these points together could noticeably reduce diamond MTF. Photos from lens with less MTF have worse sharpness and brightness than photos from lens with bigger MTF
Diamonds MTF depends from facet Flatness too. When cutters want receive good H&A pattern ( high level symmetry) they should use very good polishing disk( low vibration at least), what create better Flatness.
I think( my hypothesis ) what “true H&A“ diamonds have better light performance mainly because such diamonds have very good facet flatness ( better MTF). Parameters are important also of course, But flatness could be more important than high level symmetry .
Some tipe I1 inclusion reduce high score MTF had been created by fine facet flatness . So such diamonds can not have highest MTF and High Light Performance
strmrdr
Super_Ideal_Rock
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Past, Present, Future: The Meaning of Three-Stone Engagement Rings
Past, Present, Future: The Meaning of Three-Stone Engagement Rings - 04/14
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