Gemray vs GemrayX Image Rendering


Gemray vs GemrayX… Which is best?

I have said that I prefer Gemray and do not like the light models in GemrayX, particularly the head shadow. These are my own personal opinions and preferences. Read the article and compare the examples and see what you think. I keep hearing remarks that some how GemrayX is better than Gemray and that such and such a design is better because it was ray traced in GemrayX. GemrayX numbers seem to be the “Holly Grail” for some people. I think this is a mistake.

To begin with there is no real proof that the numbers in Gemray or GemrayX are completely accurate in the real world. I will say that Gemray has proven to be pretty accurate (to me) over the years in predicting what a cut stone will look like. GemrayX I would assume is based on Gemray to some extent, so I would expect it to be accurate to that extent. However there is no real way to test the numbers against actual real life gemstones and all computer models have some flaws.

What I am trying to say is that the numbers in both programs are just based on models and may not be completely accurate to real gemstones (although in my experiecne Gemray is pretty accurate). I would call both Gemray and GemrayX very helpful tools in gemstone designing and both have helped improve gemstone designs since their creation. I just do not think that it’s a good idea to get caught up in a numbers chase. I think that just designing for the “numbers” is a poor way to design and that there are a lot of factors in gemstones that numbers and computers cannot define.

In other words an actual gemstone needs to be cut and evaluated to really know what the stone will look like. The performance of a given design needs to actually be seen in a cut stone to get the complete picture. Ultimately cutting a stone and a design are the “real proof”of the designers work.

I obviously do not agree with people who are just chasing numbers or running a race. The numbers do give you some idea of what a design will look like but certainly not the whole picture. Also, as far as the numbers are concerned to some extent this argument on Gemray verses GemrayX comes down to Ford verse Chevy. I do think there are very clear differences in the ray trace models (pictures). But in the numbers, there is not a lot of differences or at least not much that can be compared. I especially think that arguing over numbers and a few percentage points one way or another completely misses the point of designing and creating quality gemstone designs. To me gemstones and gemstone designing is about art.

Gemray and GemrayX are both just tools. They are computer programs and have nothing to do with how good or bad a particular design is. Using either of these tools a designer can improve or refine a design. But how good a design is ultimately boils down to the designer’s talent.

OK… How do I use the tools and why? I think that Gemray gives a more accurate model of what an actual gemstone will look like when cut. What a real gemstone looks like cut is what I am personally interested in and why I use any type of ray tracing program (modeling) in the first place. To me the most important thing is that I get an accurate idea in the ray trace of a design of what an actual cut stone will look like, before cutting the stone, that is why the Gemray tool is so handy.

I personally do not care very much what the “numbers” of the ray trace(s) in either Gemcad or GemrayX come out to be. I of course, do want the performance of a design to be good, but the numbers are just a small part of what I am looking and designing for in a gemstone. In other words ray trace numbers are a part of my equation for a good design but just a part, NOT all of what makes a high performance quality design. The numbers in GemrayX or Gemray? I do not have any idea how accurate the numbers are in light return for either program, although I would say the models in Gemray are pretty accurate in my experience. How about the dispersion and scillination numbers in GemrayX? I have no idea… I also doubt there is much way to really prove those type of numbers one way or another in the real world. My point is why fight over numbers you cannot really prove?

But, here is the important point. It has been my experience from cutting hundreds, maybe thousands of stones that the finished gemstone will look pretty close to the Gemray light models. The “Random” light model in particular, at least to me, gives a pretty good general idea of what a cut stone will look like in a particular design. I tend to prefer the actual ray trace picture over the numbers. I do pay attention to the ray trace numbers and do use them but there are many factors that can change or influence the numbers one way or another, so the numbers are secondary.

Why are the numbers secondary? Here is an example. I often will make a design deeper to help color saturation of light materials like Aquamarine. Making the stone deeper lowers the ray trace brightness numbers, but helps improve gemstone color. In this case the numbers are a low priority. Yes, secondary. Also keep in mind that any ray tracing program is just a “model”. Actual gemstones have a lot of other things that influence their looks that no computer program can account for. Some of the more obvious things that affect how a gemstone looks. color, saturation, tone, hue, size. I could go on but you get the idea.

I personally think that Gemray is much better in predicting the looks of a gemstone design. Pictures are worth a thousand words, so here are my conclusions, in pictures and cut stones.

Note: All Gemray traces and GemrayX ray traces are done with both programs standard “default” setting. I am using the “default” settings because they are plain and basic starting places for both programs. “Default” setting are the place the program designer meant for the programs to be started from.

Note2: GemrayX uses a 10 head shadow for the “default” setting. I object to this, I personally do not like the head shadow. But GemrayX is built around this feature and it is what some people are claiming is better way of designing.

Here is an obvious place to start. I think most people, or at least a whole lot of people have cut my “Memory” design that is free online.

Duch Petals Item: N/A
Material: Tourmaline
Type: Light Blue/Slight Teal Highlights
Locality: Nigeria, Africa
Hardness: 7.0 good for almost any jewelry application
Design: Memory (designed by Jeff R. Graham – Memory)
Cut By: Jeff R. Graham
Dimensions: 11mm x 7.9mm deep
Clarity: IF
Weight: 5.98 carats
Price: N/A

Note: This is a very bright, lively stone and the color is very close to Paribia color (most people would probably call it that). A light blue with just some teal hints. It is very rare to find a stone this color and size, particularly in a round. This stone has an unusual girdle and may take a special setting, although I do not think it will be difficult to set for any experienced jeweler. This will wear well in most jewelry.

Below is the Gemray trace of “Memory”

Gemray vs GemrayX Rendering - Gemray trace of "Memory"

The Gemray trace is pretty much dead on to what the actual cut stone looks like. Look at the center of the stone through the table in particular. Looks just like the actual cut stone.

Below is the GemrayX trace of “Memory”

Gemray vs GemrayX Rendering - GemrayX trace of "Memory"

Looks pretty bad in the GemrayX doesn’t it? Look at the dark holes in the center of the stone in the GemrayX ray trace. As you can see in the picture of the “real” stone there is no black spot. Judging by the GemrayX model you would assume that this design is not very good and dark in the middle. Well, anybody that has cut this design can and will tell you that is not true. GemrayX gives a very poor idea of what this design looks like when cut.

Duch Petals
Item: N/A
Material: Tourmaline
Type: yellow/green
Locality: Zambia
Hardness: 7.0 good for almost any jewelry application
Design: Dutch Petals (designed by Jeff R. Graham – MIR2.JRG)
Cut By: Jeff R. Graham
Dimensions: 11.9mm x 7.6mm deep
Clarity: IF
Weight: 5.82 carats
Price: N/A

Note: This is an interesting stone. It is actually a bi color, green outside with a yellow/clear center which is not common in Zambian material, but does occasionally happen. I used this design to take advantage of the color change and as the stone is turned the colors will shift. The petals you see are an illusion and move as the stone is shifted, some times larger some times smaller. This stone is very bright and has a lot of flash. This will wear well in almost any jewelry application.

Below is the Gemray trace of “Dutch Petals”

Gemray is right on the money. Look closely at the “Mirage” petals (in the center) predicted in the Random light model and then look in my picture of the actual cut stone. They are there. Neat huh? This type of phenomenon is what “Mirage” cuts are designed to create. The “Mirage” petals float around in the crown of this design and wink at you depending on the light the stone is viewed under. But the majority of the”pedals” were never cut, are not actual facets, they are reflections caused by how the design is designed.

Below is the GemrayX trace of “Dutch Petals”

GemrayX is not even close. It does not predict the “Mirage” petals, the over all appearance in GemrayX is of a dark stone. Trust me this stone will knock your eyes out from across the room, but you would never know that if you judged by the GemrayX model.

Pink Tourmaline Heart Squared


Item:
N/A
Material: Tourmaline
Type: Pink
Locality: Nigeria
Hardness: 7.0 good for almost any jewelry application
Design: Heart Squared (designed by Jeff R. Graham – Not Released)
Cut By: Jeff R. Graham
Dimensions: 10.7mm x 11mm x 7.6mm deep
Clarity: IF
Weight: 4.04 carats
Price: N/A

Note: This is a new type of cut I am developing and it is very pretty and has interesting effect that the picture does not really show. The color of this stone is Rubellite/Hot Pink with a very slight peach highlight depending on lighting. This will set easily and wear well in most jewelry.

Below is the Gemray trace of “Heart Squared”

Gemray is right on the money. The finished stone looks just like the ray trace, particularly in the random model. Look at the double burst in the center of the Random light model and then look at the picture of the actual cut stone. Yes, both bursts are there just as predicted.

Below is the GemrayX trace of “Heart Squared”

GemrayX is closer to the mark here, but still not very accurate. The flash patterns in the actual stone are quite different then what GemrayX is predicting. GemrayX just does not show the life of the design or cut stone.

Tiger's Tape
Item: N/A
Material: Tourmaline
Type: Pink/Rubellite
Locality: Nigeria
Hardness: 7.0 good for almost any jewelry application
Design: Tiger’s Tape (designed by Jeff R. Graham – Not Released)
Cut By: Jeff R. Graham
Dimensions: 12.4mm x 8.3mm deep
Clarity: IF
Weight: 7.04 carats
Price: N/A

Note: This is a new type of cut I am developing and it is very pretty and has interesting effect that the picture does not really show. The color of this stone is Rubellite/Hot Pink with a very slight peach highlight depending on lighting. This will set easily and wear well in most jewelry.

Below is the Gemray trace of “Tiger’s Tape”

Look at the center of the Random light model above, then look at the center of the actual cut stone. Notice you will see pretty much the same shapes and patterns. Gemray is dead on in predicting them. The cut stone in fact does look like the Random light model.

Below is the GemrayX trace of “Tiger’s Tape”

Close? Not hardly, it would be very hard to judge the looks of this finished stone just looking at GemrayX. This stone was one of the first “Mirage” cuts I did by the way. The first customer that saw this stone bought it immediately and made me promise him that he would get first chance at my next “Mirage” cut stones.

Thistle
Item: N/A
Material: Tourmaline
Type: blue/steel blue/pink
Locality: Zambia
Hardness: 7.0 good for almost any jewelry application
Design: Thistle (designed by Jeff R. Graham – MIR5.JRG)
Cut By: Jeff R. Graham
Dimensions: 13.9mm x 9.7mm deep
Clarity: VVS (a couple very minute pieces of silk)
Weight: 11.01 carats
Price: N/A

Note: This is a very unusual stone. It is actually a bi color, blue outside with a slight pink center which is very uncommon. The pink center makes the stone look steel blue to blue with some pink highlights depending on the light. It can look a bit more steel or blue than the picture depending. Very striking… This stone is very bright and has a lot of flash. This will wear well in almost any jewelry application.

Below is the Gemray trace of “Thistle”

Gemray (again) dead on. The light model predicts the patterns and shapes in the actual cut stone. Look at the reflections in the center and corners. You will see the reflections in the finished stone.

Below is the GemrayX trace of “Thistle”

GemrayX? Not a close representation at all, and frankly GemrayX is very misleading in how it would predict this design and stone. It shows dead spots in the corners and center. In the real cut stone these areas are full of sparkle and movement.

I could go on with more examples, but you get the idea. As you can see with your own eyes, in the “real world” of actual cut gemstones GemrayX is not a good predictor of what a finished gemstone will look like. At least not visually in the ray trace. Which is what is important to me. In my opinion and experience Gemray is the best choice for predicting what a real stone will look like. GemrayX is just no where near as good at predicting what an actual finished stone will look like as Gemray.

GemrayX does have some applications and actually a combination of both Gemray and GemrayX can some times give a clearer picture of a design. But like I said earlier I do not think the numbers GemrayX (or Gemray to some extent) produces are provable or 100% accurate in the real world. Computer programs are just models and as such cannot cover all the various aspects of gemstones. What I am saying is gemstone designing and cutting is part science and part art. Art is some thing that is not definable, at least in a computer model. But like a judge once said “I know it when I see it…” When it comes to giving a clear picture (ray trace) of what a finished stone will look like in a given design. Gemray is by far the better program.

Note: If you set the head space on GemrayX at “0” the light models come out closer to Gemray’s light models. But the GemrayX models even with the head shadow set at “0” are not as good as Gemray models. The GemrayX models have some odd inconsistencies I do not know why.

I know there are likely people that will want to make other claims. All I can say is… I have actually designed the designs and cut the stones. Make up your own minds about which program is best, but the pictures say it all as far as I am concerned.

About the author
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
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