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PostPosted: Wed Jan 23, 2008 11:39 am 
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Anyone ready for GemWizard 'color certificates' on FleaBay? :oops: Not that it would make a hell of a difference. Joke aside, I am hoping that offering these things freely wouldn't tempt dishonest use first and foremost.

How about a little experiment with some gems, their electronic photos, GW and GemeSampler Lite ? 8)

What to do:

#1. take gem and get GW score

#2. use a reasonable photo of the same gem to get a score with the
GemeSampler

#3. report results whether they match or don't.

Obviously the tools are not 'precise' - no matter how many times the word is repeated on the front page. However, only eyeballing precision is tested here, assuming that:

- if photo matches stone 'by eye'

- and GW score matches stone by eye

- then the GemeSampler's score should match the eye-ball reasonably
well at least most of the time.


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PostPosted: Wed Jan 23, 2008 11:42 am 
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Patrick-
What system to you use to describe color?


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PostPosted: Wed Jan 23, 2008 11:56 am 
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Patrick,

Sorry, but I don't have any interest in dealing with someone who obviously has a chip on his shoulder.

J-

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PostPosted: Wed Jan 23, 2008 12:15 pm 
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Hey, and interesting test would be to use a few of the "travelling stones" and have each person then take the same stone, and using Gem Wizard describe it's color. See how close different people come on the same stone.

My problem is that the lighting I have at my PC isn't the best for viewing stones, well it's actually dark. So I'll have to set up some better lighting so I can view the stone and screen at the same time. This is one of the reasons I was thinking about purchasing the Gem Dialong set this year, since it's portable, and I can use it in my location with the best lighting.

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PostPosted: Wed Jan 23, 2008 12:22 pm 
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This is reminding of a long retired diamantaire's stories of his profession's almost rabid resistance to GIA diamond color grading system in the early years which was fully accepted towards the end of his career as one of the most useful means of communicating diamond color....over the phone. He also related how he took the first color stone course to the amusement of his colleagues who disdained colored stones at the time.

The diamond reference stones used in the lab and which dealers buy smaller sets of as the most authentic way of matching stones, are leagues away from the images or CZ sets and other material sets which apparently change color with time and of course don't have the other aspects of diamond which affect perception.

Issues such as calibration are going to plague any computer program just as printed materials and plastic materials are going to have their drawbacks. And colored stones are so much more complicated than diamond color....it is amazing anyone is trying to quantify them.

I would just like to reiterate to the gemology students on the Forum, especially distance students, that this program is just one tool that you can now access to start to understand this color grading system. Then start reading Secrets of the Gem Trade and color theory books and expand your understanding further. If you plan to use resources such as The Guide or appraisal software ( or deal with people who do), you have to be at least familiar with this system which is starting to be embraced.


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PostPosted: Wed Jan 23, 2008 12:38 pm 
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brimsjewelry wrote:
Patrick,Sorry, but I don't have any interest in dealing with someone who obviously has a chip on his shoulder. J-
In re-reading the thread, I don't see any chip anywhere (even with my new 20x loupe :lol: ), just raising very insightful concerns that generate discussion useful to all. Keep going!


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PostPosted: Wed Jan 23, 2008 12:41 pm 
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You are quite right. Patrick pm'd me and this has been cleared up. I messed up.

Jason

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PostPosted: Wed Jan 23, 2008 12:56 pm 
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Noone messed up. I am sometimes a bit bold in my statements. Blame my Dutch nature with a southern temperament. No intention whatsoever to insult, or offend anyone. Moreover did NOT imply any bad business practices of anyone on this forum. How could I.

I am simply *very irritated* by their approach (and I guess by the reception I received, when I was genuinely interested last year in Tucson).

I think innovation in the jewelry industry is very very important, given the dramatic changes. My objections are not a resistance to change. I love change. My objections or hesitations were other.

By the way.. there IS more than the GIA on this planet, and many organizations in Europe do approach things differently than the GIA. And now there's Asia as well. So it's gonna be a very very diverse group of ideas, approaches and "truths". Just to let you know guys.. :D :D :D

HTH

Patrick

Oh.. I love Secrets of the Gem Trade.


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PostPosted: Wed Jan 23, 2008 1:11 pm 
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I'll add my comments here as a non partisan gemologist who derives no income from the gemological industries and consequently has no industry shoes to shine or bridges to burn.

There are more than enough debates concerning the intricacies of gem sciences. Color is a big one as well as mundane arguments about crown and pavilion angles on diamond cuts and their affect on light performance, argued ad nauseam to the point that would render any human eye irrelevant to what is seen.

Experts and theorists seem content to blather away the weeks and years telling us why things won't work instead of considering why they may work and work well within an intended parameter.

What is so difficult about comparing a gemstone color to a colored monitor image? Is it any different than taking your gem to Sherman Williams and matching a paint paddle? Any normal eyesight should be able to do this within a reasonable degree of subjectivity. Remember, we are talking about color, not every other factor involved that gives the gemstone optical individuality.

Monitor arguments be damned. The final decision on the gemstone color will hardly ever be decided by monitor or photo renderings anyway, if done properly. It is merely a way of communicating color within that reasonable range of subjectivity and final decisions will be made by in hand inspection within each individuals own unique viewing requirements.

This hands on inspection should always be allowed for in the terms of sale between seller and buyer.

Programs like GemeWizard allow buyers and sellers to eliminate hundreds of possibilities to a vary narrow range of a few. The rest can be sorted out with an actual viewing.

Can anyone think of a better way of communicating between novice and expert? I've seen several examples on these forums already of GemeWizard samples matching gemstone photos submitted by members.

I suspect that while all the theorists are arguing points of acceptable compliance, business is being transacted daily using these color grading programs within an acceptable "tolerance of the trade" and software limitations.


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PostPosted: Wed Jan 23, 2008 1:41 pm 
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Say, this is a big deal. It is going to take a minute to acquaint myself with the program but then. I always had trouble with tone and masking using the paddle type stones and then following with the Guide to establish marketability, but this will be invaluable. I also use as a quality of light reference Hofer's book on Coloured Diamonds. Thanks to all for bringing this to my attention. Phil


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PostPosted: Wed Jan 23, 2008 1:47 pm 
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Several things:

1) I am not representing a gem dealer, jeweler, laboratory etc. Therefore neutral as well.

2) I find your argument illogical:

2a) Either you create a level of precision by drilling down several levels of hues etc. the way GEW does, with the objective to be precise, and it having a meaning.

2b) Or you say.. to hell with everything, we do it face to face and then we decide. I will tell you "kinda" which color it is, so you know it's in the right direction, but the devil is in the detail, and your "pink" may not be this "pink". And so you must see it for yourself.

But you can't have it both ways.

In either case.. it's a great user-interface, and therefore makes things *easy* to use. Cool. Very Cool. And that's it. I am not trashing it. But... that is not what they are aiming to achieve ! In their marketing they make quite clear, it is 2a) they are after: creating a level of precision in your color communication. and THEN you cannot say.. forget about all the potential errors, we need to do it "live" or "face to face" anyway.

It's the same as saying... Mike Huckabee is 4 % ahead in the polls.. and will surely win... and hey.. forget about the margin of error of 5 % in this survey. We all know what these errors in surveys have led to in the primaries so far :-)

(BTW I am NOT endorsing MH or any other candidate on this forum...) :-) :-) :-)


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 Post subject: Re: GemeWizard: Free to all!!!
PostPosted: Wed Jan 23, 2008 2:05 pm 
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Good intentions, but hardly a tool to "make this dream of a common color language a reality".
Without a physical point of reference in the form of something like a GIA set ( which this software
is based on) and colour profile ( conditions when stone was graded and viewed) this system is pretty
much useless, because:

1. Seller( colour grader) and Buyer ( stone viewer) must have at least exact same video card and
monitor in order to see same colour and therefore agree on the grade.

2. Using digital photograph to colour grade the stone will not "accurately describe a gemstone's color",
because real colour of the stone will not be accurately described by the photograph. There are hundreds
of factors which will affect gemstone colour in the photograph: background, lightening profile, camera
sensor, color balance setup, image compression, angle, etc.

3. Lighting conditions when stone was photographed and graded must be disclosed and taken on account.

4. This system does not answer colour change and play of colour issues. It's also doesn't describe
colour zoning correctly, because converting gemstone photo into the RGB colour pallete and calculating
percentage of dominant colours, is not stone grading, but image colour profiling.

5. I fail to see any practical use of this system, even for the GIA students. To grade the stone, someone
will need to take a photo of the stone. Minimum setup ( to get the colours right) for gemstone photography
is about 8000 USD. Plus this software (GemSquare) is 450 USD. You will be a lot better with the GIA set
which is 1200 USD and can do colour grading job 10 times faster (and better), assuming you are not colour blind.
Also, all this colour codes and grades are pretty much useless in the trade, since most of the gemstone
dealers and jewellers don't use any colour standards when describing colours of the gems.

Based on my experience, which is 5 failed implementations of the colour grading systems for the Internet trading
of the colour gemstones ( including GIA set replication) -- between two remote parties ( seller and buyer),
colour code or color description for the gemstones only works when both parties have a physical sample of
the colour in the form pantone, or an actual stone ( sampler).

On the final note, here is a good topic to read.

Describing Color in Gemstones, Color Communication.
http://www.multicolour.com/catalogue/co ... 12002.html


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PostPosted: Wed Jan 23, 2008 2:22 pm 
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Well I'll probably get my head handed to me in a basket .. but here goes.

Situation #1:

Hi gemn00b I've got a kinda blue .. hmm kinda green sapphire here and I'm looking for a match for it so I can make a pair of earings, can you help me out?

Now poor ole gemn00b has pretty much gotta guess what i'm looking for and will probably not have much luck ...
Result: frustrated gemn00b .. frustrated me

Situation #2

Hi gemn00b I've got a blue sapphire here close as I can come is its a #30 on that Gemewizard program, can ya help out here I need a match for it for a pair of earrings?

Now gemn00b has a pretty good idea what I 'm looking for and yup he has 4 stones of the proper size and pretty near #30's on his Gemewizard.
He gets back to me and sends them to me I lookem over and say yup this one is close enough for government work .. send him back the other 3 and payem for the one I kept.

Result happy gemn00b .. happy me

So I leave it to you guys .. it may not be perfect but it serves a purpose.

Some times close enough is good enough :)

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PostPosted: Wed Jan 23, 2008 2:24 pm 
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Patrick,

I think it is you that has missed the point between "color matching" and gemstone evaluation. "Matching" is a simple exercise of comparing sample A to Sample B. Evaluation requires hands on examination.

No software program will ever replace hands on examination, but , it may be able to effectively replicate an individual color within a reasonable tolerance.

If you are making a determinative purchase based on a computer image, then your buying skills need to be sharpened. If you are trying only to find an acceptable color range or communicate that range, then these programs are adequate.

Despite any claims made by the vendor, we all realize that these programs are merely a tool and communication device. Easy enough for two subscribing parties to say, "Do you have any XYZ tourmalines in the XYZ color range according to GemeWizard's color palette." "I'm trying to match some existing stones in this range for a client."

If you expect anything more from the program, you'll probably be disappointed.


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 Post subject: Hypothetical
PostPosted: Wed Jan 23, 2008 2:34 pm 
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Wolf: how about:

3) Hi Gemn00b: Here is a photo of a stone I really like. Do you have something like this for me ? If so send me some pictures. If I like it, obviously I would like to see the stones in person. Can we meet somewhere or can you send them to me.

Sending a photo back and fourth, or using GemEWizard, *without* calibrating both screens, and taking all previous arguments into consideration (lighting etc etc etc) creates such an accumulation of errors that the result is the same. The same precision range. THAT is my point.

If GEW claims they can create a much higher level of precision, then I am sure, GEW has all the documentation and testing available to proof it.

Now take
4) Hi Gemn00b: I want # 30 GEW color stone. OK here they are, I'll send them to you. You live on another continent however... so... can you send me the cash. Sure I say.. I'll send it.. you're sure it's color #30 right ? Yeah.. it is. I get the stones... and... guess what ? It's not what I wanted.

Now Gemn00b is way too experienced to get involved in a deal like that, but how many people would make that mistake ? And then what ?


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