Spread =Apparent size explanation

[jasper]

Is "Asher" a misspellling of "Asscher"?

The calorie discussion is contradictory, confusing, and not completely accurate. In the dessert discussion, the number of calories is a constraint. In the hiking discussion, the number of calories is a feature to be maximized. In the first subsequent use of calories in the diamond video, it is not clear whether calories are being treated like spread (a feature) or like mass (an expense). Also, one of the illustrations has a scientifically incorrect use of "calories". Most desserts have "Calories", or thousands of "calories".

Also, consider having a native speaker of English proofread the script. In particular, many determiners (like "a", "the", "this", "that", and "these") are missing.

 

[OoohShiny]

For me, I think a small part showing a side-on view and how changing the depth can change the stone's profile (and therefore spread) could be useful.

e.g:

Show a Tolk 1ct stone side on.

Place vertical lines at each side of the girdle extremities.

'Morph' the stone into a steep/deep stone of 68% depth.

Place new vertical lines at each side of the girdle extremities.

Show the difference between the vertical lines of the Tolk and the deep stone.

Measure the difference.

Add to the screen a top-down view of the Tolk stone and a top-down view of the steep/deep stone.

Show how the difference illustrated with the vertical lines translates into a difference in size when seen from the top - perhaps by showing the surface area calculation.



This is a terrible graphic and I'm certain the calculations are wrong... but it sort of illustrates my thinking.

It is kind of an extension to the 'comparison on the hand' graphic and % difference in size calculations on diamdb (that we aren't supposed to link to) but illustrates the '3D' aspects by showing what the stones look like from the side:




You could go the other way as well, and show how a 60/60 might be spreadier than a Tolk?

At that point, you could move into showing side-on line drawings of light moving through the different cut options, and then discuss how light performance trade-offs enter the discussion (perhaps linking to the video that @Garry H (Cut Nut) has on Youtube, showing 'in real life' how poorly cut stones look smaller for an identical weight by not sparkling at the edges).



EDIT:
The above may be me totally misunderstanding the question, though so please feel free to ignore!


EDIT 2:
I think a super-short mention of Tolk and what he did to get to his 'recommended' angles proportions would get Tolk into the discussion as a reference point.

The fact that modern science has measured his proportions as close to 'best' for light performance in MRBs can be mentioned.

Tolk would then be set up as the 'reference' stone proportions, against which spread of alternative proportions can be measured as a + or a - spread.

That would cover off MRBs. Fancies are trickier... but a brief mention of fancies at the end of a video focused on MRBs could point to another video on fancies (if people are interested) or just be used to show how MRBs compare to different shapes (which people might not even be aware of).

The 'spread' concept would then be in the mind of the person if/as they looked at fancies, so the concept would (hopefully) be carried across by the viewer without too much need to explain further?


One could also argue that buyers know what shape they want and shop only amongst that shape - in which case, comparisons between MRB and other shapes is moot... it is the comparisons between stones of the same shape that is most important, and the Spread concept/comparison is probably easy to carry over from one shape to another?

 

[Garry H (Cut Nut)]

How is this OShiny?
https://youtu.be/t8ZN2bfQmKQ

 

[Serg]

Is "Asher" a misspellling of "Asscher"?

The calorie discussion is contradictory, confusing, and not completely accurate. In the dessert discussion, the number of calories is a constraint. In the hiking discussion, the number of calories is a feature to be maximized. In the first subsequent use of calories in the diamond video, it is not clear whether calories are being treated like spread (a feature) or like mass (an expense). Also, one of the illustrations has a scientifically incorrect use of "calories". Most desserts have "Calories", or thousands of "calories".

Also, consider having a native speaker of English proofread the script. In particular, many determiners (like "a", "the", "this", "that", and "these") are missing.

Thank you for your comments. We have just finished movie
Help clients enjoy your diamonds, by identifying and solving obstacles
with a native english speaker.
Now we are going to improve Spread movie .

 

[OoohShiny]

How is this OShiny?
https://youtu.be/t8ZN2bfQmKQ

Oooooh, thank you for creating and uploading the video!


My first thought is... Whoa!! Information overload!! lol

I think I'm trying to focus on the changing C and P angles, the ASET changes, the depth changes... and they come together and fast!

(Is the 'Parameters Quality' box the AGS score for Cut?)


That said, I think this is a really good demo of how changing parameters affects performance

If it is to be used solely for Serg's spread discussion, I think it might need to be tweaked so that rather than ct weight rising and falling on a fixed diameter stone, the ct weight stays fixed and the diameter is the changing factor. I'm not sure if that would be a total PITA to do, though?

If it could be done, would I be right in thinking one could see the ASET image increase and decrease in size? If not, it's not an issue - highlighting the changing diameter would just need to be done to make sure the viewers' attention is directed to it.

(Perhaps a 'freeze screen' at the start, with some highlights added on the information being looked at (depth, C, P, diameter, Ct) would enable talking through what's being shown and help 'noob' viewers know what to focus on?)


Thanks again - I am going to bookmark that for future reference


EDIT: I forgot to say - the 59% depth stone seems to perform remarkably well in ASET??

 

[jasper]

Serg,

Thank you for sharing the video about creating a variety of diamond cut "personalities". The video makes a strong case.

Here are two easily-fixed errors in the video:

1. One of the illustrations shows blueberries, but calls them "blackberries".
   
   
2. The time reference for the "super-duper ideal" cut is wrong. This can be fixed by changing "Pre-digital age" to "Early days of the world wide web" (in the voice over) and "Early WWW" (on the chart).

Here is an explanation of why the time reference for the "super-duper ideal" cut is wrong:

In reality, the pre-digital target was taken directly from Tolkowsky (http://www.folds.net/diamond_design/index.html#ideal) without explicitly accounting for the girdle or his rounding errors. The target had

• a circular girdle,
• a 53% table,
• 40.75° pavillion angle,
• 34.5° crown angle, and
• 59.3% total depth.

This combination was impossible, so unfortunately large tolerances were applied.

The video's "super-duper ideal" cross-section was a reaction during the first decade of the World Wide Web by several parties (including engineers, cutters, retailers, and customers) to both the impossible target and the excessive tolerances of the pre-digital standard.

 

[Garry H (Cut Nut)]

Thank you for your comments. We have just finished movie
Help clients enjoy your diamonds, by identifying and solving obstacles
with a native english speaker.
Now we are going to improve Spread movie .

Vastly improved Sergey. I think it is still 3 times at least too long and the key takeaways are too many.

 

[Garry H (Cut Nut)]

Oooooh, thank you for creating and uploading the video!


My first thought is... Whoa!! Information overload!! lol

I think I'm trying to focus on the changing C and P angles, the ASET changes, the depth changes... and they come together and fast!

(Is the 'Parameters Quality' box the AGS score for Cut?)


That said, I think this is a really good demo of how changing parameters affects performance

If it is to be used solely for Serg's spread discussion, I think it might need to be tweaked so that rather than ct weight rising and falling on a fixed diameter stone, the ct weight stays fixed and the diameter is the changing factor. I'm not sure if that would be a total PITA to do, though?

If it could be done, would I be right in thinking one could see the ASET image increase and decrease in size? If not, it's not an issue - highlighting the changing diameter would just need to be done to make sure the viewers' attention is directed to it.

(Perhaps a 'freeze screen' at the start, with some highlights added on the information being looked at (depth, C, P, diameter, Ct) would enable talking through what's being shown and help 'noob' viewers know what to focus on?)


Thanks again - I am going to bookmark that for future reference


EDIT: I forgot to say - the 59% depth stone seems to perform remarkably well in ASET??

Hi OhShiny,
I am using a defined variance method inside DiamCalc - so cant change as you request.
I did not make it for Sergey - I made it for you
Yes - the AGS parameters are changing as the depth goes up and down.

 

[OoohShiny]

Hi OhShiny,
I am using a defined variance method inside DiamCalc - so cant change as you request.
I did not make it for Sergey - I made it for you
Yes - the AGS parameters are changing as the depth goes up and down.

You are far too kind, thank you!

I think it's a really useful video - I shall be linking to it in future posts as a way to illustrate the importance of good proportions and the use of the HCA tool to support that!

I think it would work well alongside Serg's? Yoram's? tables of ASET and IS images for C and P combos (that might also be on the WF website??), as a more dynamic way of showing how results change as parameters change

I think it could also be useful in showing there is some flexibility away from a strict HCA<2 / AGS000 / P<40.9 approach, which (IIRC...?) I've seen mentioned by yourself and Serg as a way to capture some good value options e.g. HCA<2.5ish (you) and a different visual 'flavour' with less obstruction and more fire (Serg) - some of the stones with scores higher than AGS0 do still look like they have decent ASET images (in that there is not a huge amount of leakage or obstruction issues)!


I think? Maybe??

I doubt my own thoughts sometimes!!! (Ok, most days... lol)

 

[Garry H (Cut Nut)]

You are far too kind, thank you!

I think it's a really useful video - I shall be linking to it in future posts as a way to illustrate the importance of good proportions and the use of the HCA tool to support that!

I think it would work well alongside Serg's? Yoram's? tables of ASET and IS images for C and P combos (that might also be on the WF website??), as a more dynamic way of showing how results change as parameters change

I think it could also be useful in showing there is some flexibility away from a strict HCA<2 / AGS000 / P<40.9 approach, which (IIRC...?) I've seen mentioned by yourself and Serg as a way to capture some good value options e.g. HCA<2.5ish (you) and a different visual 'flavour' with less obstruction and more fire (Serg) - some of the stones with scores higher than AGS0 do still look like they have decent ASET images (in that there is not a huge amount of leakage or obstruction issues)!


I think? Maybe??

I doubt my own thoughts sometimes!!! (Ok, most days... lol)

We are hijacking this thread OS - I will start a new one shortly

 

[Karl_K]

@OoohShiny just for you: 1 degree difference in the pavilion no other changes. 57t 34.5c 50%stars and 77% lowers for both.

 

[Serg]

Serg,

Thank you for sharing the video about creating a variety of diamond cut "personalities". The video makes a strong case.

Here are two easily-fixed errors in the video:

1. One of the illustrations shows blueberries, but calls them "blackberries".
   
   
2. The time reference for the "super-duper ideal" cut is wrong. This can be fixed by changing "Pre-digital age" to "Early days of the world wide web" (in the voice over) and "Early WWW" (on the chart).

Here is an explanation of why the time reference for the "super-duper ideal" cut is wrong:

In reality, the pre-digital target was taken directly from Tolkowsky (http://www.folds.net/diamond_design/index.html#ideal) without explicitly accounting for the girdle or his rounding errors. The target had

• a circular girdle,
• a 53% table,
• 40.75° pavillion angle,
• 34.5° crown angle, and
• 59.3% total depth.

This combination was impossible, so unfortunately large tolerances were applied.

The video's "super-duper ideal" cross-section was a reaction during the first decade of the World Wide Web by several parties (including engineers, cutters, retailers, and customers) to both the impossible target and the excessive tolerances of the pre-digital standard.

@jasper
1) The reason of large tolerance is not Tolkowsky math simplifications. The reasons are technology limitations and profit
2) "Tolkowsky parameters combination " had been used at least by his uncle before the Tolkowsky math calculations .

 

[Serg]

Vastly improved Sergey. I think it is still 3 times at least too long and the key takeaways are too many.

@Garry H (Cut Nut)
The video is for decision makers .

 

[OoohShiny]

@OoohShiny just for you: 1 degree difference in the pavilion no other changes. 57t 34.5c 50%stars and 77% lowers for both.

Wow - that is a marked difference!



Thank you for taking the time to put it together!

I'm now thinking of questions re: Serg's previous comments that he prefers a deeper pavilion because it works better off-axis, and how visible leakage is / how it can be compared to contrast... but I think that is for another thread lol