Evaluating Online Photos, Vol 2

[JewelFreak]

Could some of you more experienced folks give me more advice on how to look at photos -- we know you need to see the stone IRL to be sure if it's good or not, but I still want to know how to do it online the best possible, though nothing is certain from a pic. Sorry this is so long, will include all the info.

Here's why I'm confused. The tsavorite I ordered from Tan is first, then OUpeargirl's gorgeous one, which she just put up. Several people commented on the one I ordered being windowed, but OUpeargirl's not. The photos look pretty similar to me: What am I missing? (This is not a criticism of your beautiful purchase, OUpeargirl, in any way -- your pic just happened to illustrate the question I already had. It's gonna make a wonderful ring with the diamonds!) I'm mainly asking for advice from you expert types!

Please help me clarify this. When looking at the listing for the tsavorite, I watched the video a zillion times -- didn't see a window as it rotated, it looked more like reflection of the light source off the facets (unless it's a gigantic angle window). But to produce a window that big, wouldn't the pavilion need to be cut really really shallow? Dimensions are 7.5 x 6.2 x 4.2, not an exceptionally deep pavilion but surely not a very shallow one either. Photo of the pavilion looked symmetrical, no weird angles. Faceting is ok.

For comparison I'm also including a pic from a past Sotheby's catalog. This sapphire shows the same sort of reflection that might lead one to think it's windowed -- not likely, with the amount it sold for. Help!

Any advice or experience would really be appreciated!

--- Laurie

 

[billyboo]

The OUpear stone is a tilt window. Many stones have them especially the lower RI stones. If you have something like an amethyst/quartz chances are it will have a tilt window to some degree. A stones cut has the light traveling through the table to the pavilion and back out to your eye. if angles are correct it will bounce back and no window will be present..thats face up but when you tilt a stone like OUPear's the angles are not meant to bounce light through the table to the pavilion and back to your eye from that tilted angle so a window appears. You don't know if it's "windowed" in the true sense since it's not a straight on shot. The top stone is not windowed horribly and should close up. It's picture is from straight on. You can see the lower facets in the windowed area are bouncing light back..for a windowed stone this is a good sign. It means if you ever so slightly tilt the stone downwards those bottom non-windowed facets will move up to the top ones then the bottom(pavilion facets in the windowed area) ones will be the windowed ones. It's a good sign for an "already windowed" stone since it means the angles are only slightly off and not to terribly bad. A window can be a lot worse. If those bottom facets were not reflecting any light I would say pass. Should close up and not be noticable if set right.

That bottom photo it's hard to tell. The photographer didn't use much lighting, well not like the other 2 photos. You can barely discern any facets in the photos. Just a slight reflection here and there where as the two other stones you can see lots of reflections and facets(they have more facets than the sapphire but you get my jist). Not much light directed into the stone. It seems to me as more of an ambient type lighting. Bill Boon

 

[chrono]

Let me preface by stating that judging any gem via photography isn’t the most accurate or the best method, but we all make do wherever we can unless one wants to spend a fortune on shipping stones back and forth. Not that that is out of the way, let’s move on to your questions.

JF,
I would not consider your stone to have a huge window. Yes, it is there but should appear to close up once set. I’m not sure who said OUpg’s tsavorite is not windowed but it has a small window to me. You cannot see it in this particular picture you posted because it is angled but you will see it in her thread where there is a head on picture. The easy way to tell is the lack of colour (or huge contrast in colour) at the very center of the stone in the picture where the culet is. If the stone has a rich colour everywhere except the center (a dull center), then it is windowed. The larger this area of contrast is, the larger the window will be. Always remember that this is only judged if the stone is looked straight down the table (not angled). Windowing will also happen in deeply cut stones, not just shallow stones if the last 3 tiers of the pavilion are not cut to the critical angles. It doesn’t have to be off symmetry either.

As to Sotherby’s or other very high end stones, believe it or not, many are windowed to maximize the carat weight of such fine material because each 0.1 carat wastage is a huge sum of money due to the rarity factor.

 

[Arcadian]

Like Chrono said, both have windows but are small. I don't really have an issue with small windows, though some find them to be unacceptable.


So a stone with a window bothers you, it will not be worth your time to bother with this stone.

most of my stones sans the a few of the precision cut ones have a tilt window. They don't bother me since I don't tend to look at stones from the sides.


If you're going to set it, it should close with no problem, so I wouldn't worry about it unless the window was so big you could yodel through it.

-A

 

[Arkteia]

I have noticed that if there is even a hint at a window in Tan's picture, there will be a window in the stone. The effect, really, depends on the color of the stone. My first stone, a lemon chrysoberyl, had a window, and it was a significant issue due to overall light color of the stone. I did not expect it to close. The second chrysoberyl, a stone that I recently posted, has a window, but it is narrow and the color of the stone is saturated, so I expect it to close.

Your stone definitely has a window, but the color of the stone appears very nice, so I do not expect it to affect the beauty of the stone. And it will close in a setting.

 

[JewelFreak]

Windowing will also happen in deeply cut stones, not just shallow stones if the last 3 tiers of the pavilion are not cut to the critical angles. It doesn’t have to be off symmetry either.

Thank you, Bill, Chrono & Arcadian for your input. Your point, Chrono, about angles in the last 3 pavillion tiers is a good reminder, correct angles being individual to each gemstone too. I do realize the proof is in holding the puppy in your hand, with a loupe in your eye. Which I intend to do as soon as I get it, if I do, with the odd stuff going on at Odyssey et al.

I hope it doesn't sound like I object to a critique of "my" stone; that's exactly why I put it up. Just want to learn as much as possible.

Not to beat a dead horse, but everybody mentioned the sapphire from Sotheby's -- here is the photo, big enough to see a few things. This sapphire is 14.4 ct, which accounts for some of the price -- the catalog listing isn't still up so don't know about treatment. Part of the price could be the quality of the diamonds, don't know about them either.

However, from a mere photo I can't see why anybody would pay $84 grand for this, egg-sized or not. Dull, as you all mentioned, in the center looking straight down. And, at the right of the table & on some of the crown faceting, it seems like you can see straight through to the sidestones (or is the sapphire reflecting the diamonds?). Granted, allowances have to be made for the lack of sparkly lighting. But it does make me extra critical of photos because I simply can't imagine Sotheby's would put a gem so defective into a "Magnificent Jewels" auction in Switzerland, where the most knowledgeable people attend, and further, that somebody'd pay that much for it. So it must be a much better sapphire IRL than it photographs. Sigh!

-- Laurie

ETA: Thanks, Crasru. You posted while I was writing. Good news -- let's see if I get the critter now! I do plan to set it, probably w/a halo. Not till I lose some weight, though -- it's my carrot!

 

[Arcadian]

I think in some cases pedigree does matter when it comes to price. I have no idea about this stone, but if its papered with origin, yes, the price can jump just for whats on that paper.

Keep in mind, this is a set stone versus unset, so its kind of apples and oranges to some degree.

Also too, lets look at those 2 very unsmall diamonds and if the setting is high-grade heavy gold or platinum, well...

However, the color of the stone looks to be even. the color is not dark and looks like it may have silk (which could mean unheated), also too, I happen to like the color. Not for 84 grand, but well...if you have it to spend....

A stone with enough silk in it will glow instead of sparkle.

So though it may have a window (looks as if it might), there are other factors that have to be taken into account.



-A

 

[Michael_E]

I do realize the proof is in holding the puppy in your hand, with a loupe in your eye.

Exactly. Oh and forget the loupe when making your final judgement about a stone. A loupe is nice the see exactly what's going on inside a stone, but assuming that you don't find anything glaringly wrong under the loupe, you need to put the loupe down, open both eyes and look at the stone in the way that you and everyone else will be seeing it when it's finally mounted and being worn. You need to remember that a camera only has one eye and so does a loupe. You have two eyes and when the signals from your eyes meet in your brain, they mix and give you a composite view of the stone. This is what the stone "really" looks like and this is what it is being sold as in almost every venue in the world.

This forum and the internet are unique in that all that you have to view and communicate with are pictures. You can't be a connoisseur of pictures because every one is different and none of them can accurately portray what that stone will look like in your hand and under dozens of different lighting scenarios.

I hope it doesn't sound like I object to a critique of "my" stone; that's exactly why I put it up. Just want to learn as much as possible.

A critique from an image is difficult at best and anyone being overly critical of any but the most blatantly obvious problems with a stone is blowing smoke. The image of your stone for instance has no background. Without a background it is impossible to get any clues about the lighting around the stone. Without knowing about the lighting it very hard to guess anything about the actual saturation of the stone. At a guess I would say that the saturation is pretty dark and this is based on the contrast between the brightest reflection and the areas with no reflection. Too dark? Who knows. Under bright lighting which has no or very little diffusion, digital cameras will make a stone look like there is more contrast than there really is, making dark areas look darker and light areas very bright. On the other hand a little Photoshopping can make the dark areas appear less saturated and the stone look much better than it is. A person just has no clue without a background to use as a guide. If the seller of your stone is O.K., then the stone is probably O.K. as well, but you just have to see it in hand to make a judgement on it.

Oh, the window? No big deal. It's much smaller than the table and the table is not all that large anyway. The image is magnified by at least 10 times it's actual size and the stone is strongly saturated, so I think that you'll have a hard time seeing a window once the stone is set in a ring and on your hand. Also remember that ALL colored stones will show a tilt window under the table, some at 5 degrees of tilt and some closer to 20 degrees, but they all do it. I can't figure out why people are constantly bringing up the subject of tilt windows when they are "built in" to every colored stone in existence. If it bothers you then you'll just need to get stones with small or no tables, since that is the area of the stone in which this shows most dramatically.

Not to beat a dead horse, but everybody mentioned the sapphire from Sotheby's -- here is the photo, big enough to see a few things. This sapphire is 14.4 ct, which accounts for some of the price -- the catalog listing isn't still up so don't know about treatment. Part of the price could be the quality of the diamonds, don't know about them either.
However, from a mere photo I can't see why anybody would pay $84 grand for this, egg-sized or not. Dull, as you all mentioned, in the center looking straight down.

Let's see, at $5k per carat that stone is worth $72,000. The diamonds are probably around 2 carats each and these would be worth, what, maybe $12,000 each. Now, we're up to $96,000. Add in the setting and any provenance at probably $10k and we're up to $106,000...looks to me like whoever got that baby for $84K got quite the bargain. Dull? Hmm, so are Kashmir sapphires. COLOR is king with sapphires and I think that, in hand, this stone is probably worth much more than the price paid. I would even go so far as to say that it probably "glows" as much as any of the pink spinels seen here, except that it's a huge sapphire. No this one got away cheap.

And, at the right of the table & on some of the crown faceting, it seems like you can see straight through to the sidestones (or is the sapphire reflecting the diamonds?). Granted, allowances have to be made for the lack of sparkly lighting.

Where does the light come from which you see around the edges of a high R.I. stone like sapphire? It can't go straight into the stone, since it bends inwards as it enters. Because if this you can never have a window at the edge of a stone and never see anything through the edge, (which is nice because that's a great place to hide small naturals and inclusions).

The color of this stone is probably much better in person too since that picture looks like it was taken in a fluorescent light box. The light in these is very diffuse and being fluorescent can make sapphires look pallid. Taken under the right kind of lighting I think that ring would make your head spin

But it does make me extra critical of photos because I simply can't imagine Sotheby's would put a gem so defective into a "Magnificent Jewels" auction in Switzerland, where the most knowledgeable people attend, and further, that somebody'd pay that much for it. So it must be a much better sapphire IRL than it photographs. Sigh!

The stone is not defective, the picture is. This an excellent example of an image which is not designed to show the better points of this piece, meaning that this picture will not sell this ring. The ring did sell though, so as you say, it must have been much better in person.

You should be VERY critical of pictures. They are too easy to manipulate and should only be used in conjunction with price and a sellers reputation to give a VERY vague idea of whether a gem is worth looking at. I've seen a number of pictures of stones come up on this forum which were highly criticized but which that I thought were really nice stones. If you consider the possibility of a slight pavilion recut and modest initial prices, some of the stones that get a royal beating on here are in reality fine bargains.

How do you tell a frog from a potential prince? Easy, get not only a top view, but at least one side view. From the side view you can easily tell if the angles are decent and what would be required to massage a marginal stone into a great stone.

 

[Aoife]

I do realize the proof is in holding the puppy in your hand, with a loupe in your eye.

Exactly. Oh and forget the loupe when making your final judgement about a stone. A loupe is nice the see exactly what's going on inside a stone, but assuming that you don't find anything glaringly wrong under the loupe, you need to put the loupe down, open both eyes and look at the stone in the way that you and everyone else will be seeing it when it's finally mounted and being worn. You need to remember that a camera only has one eye and so does a loupe. You have two eyes and when the signals from your eyes meet in your brain, they mix and give you a composite view of the stone. This is what the stone "really" looks like and this is what it is being sold as in almost every venue in the world.

This forum and the internet are unique in that all that you have to view and communicate with are pictures. You can't be a connoisseur of pictures because every one is different and none of them can accurately portray what that stone will look like in your hand and under dozens of different lighting scenarios.

I hope it doesn't sound like I object to a critique of "my" stone; that's exactly why I put it up. Just want to learn as much as possible.

A critique from an image is difficult at best and anyone being overly critical of any but the most blatantly obvious problems with a stone is blowing smoke. The image of your stone for instance has no background. Without a background it is impossible to get any clues about the lighting around the stone. Without knowing about the lighting it very hard to guess anything about the actual saturation of the stone. At a guess I would say that the saturation is pretty dark and this is based on the contrast between the brightest reflection and the areas with no reflection. Too dark? Who knows. Under bright lighting which has no or very little diffusion, digital cameras will make a stone look like there is more contrast than there really is, making dark areas look darker and light areas very bright. On the other hand a little Photoshopping can make the dark areas appear less saturated and the stone look much better than it is. A person just has no clue without a background to use as a guide. If the seller of your stone is O.K., then the stone is probably O.K. as well, but you just have to see it in hand to make a judgement on it.

Oh, the window? No big deal. It's much smaller than the table and the table is not all that large anyway. The image is magnified by at least 10 times it's actual size and the stone is strongly saturated, so I think that you'll have a hard time seeing a window once the stone is set in a ring and on your hand. Also remember that ALL colored stones will show a tilt window under the table, some at 5 degrees of tilt and some closer to 20 degrees, but they all do it. I can't figure out why people are constantly bringing up the subject of tilt windows when they are "built in" to every colored stone in existence. If it bothers you then you'll just need to get stones with small or no tables, since that is the area of the stone in which this shows most dramatically.

Not to beat a dead horse, but everybody mentioned the sapphire from Sotheby's -- here is the photo, big enough to see a few things. This sapphire is 14.4 ct, which accounts for some of the price -- the catalog listing isn't still up so don't know about treatment. Part of the price could be the quality of the diamonds, don't know about them either.
However, from a mere photo I can't see why anybody would pay $84 grand for this, egg-sized or not. Dull, as you all mentioned, in the center looking straight down.

Let's see, at $5k per carat that stone is worth $72,000. The diamonds are probably around 2 carats each and these would be worth, what, maybe $12,000 each. Now, we're up to $96,000. Add in the setting and any provenance at probably $10k and we're up to $106,000...looks to me like whoever got that baby for $84K got quite the bargain. Dull? Hmm, so are Kashmir sapphires. COLOR is king with sapphires and I think that, in hand, this stone is probably worth much more than the price paid. I would even go so far as to say that it probably "glows" as much as any of the pink spinels seen here, except that it's a huge sapphire. No this one got away cheap.

And, at the right of the table & on some of the crown faceting, it seems like you can see straight through to the sidestones (or is the sapphire reflecting the diamonds?). Granted, allowances have to be made for the lack of sparkly lighting.

Where does the light come from which you see around the edges of a high R.I. stone like sapphire? It can't go straight into the stone, since it bends inwards as it enters. Because if this you can never have a window at the edge of a stone and never see anything through the edge, (which is nice because that's a great place to hide small naturals and inclusions).

The color of this stone is probably much better in person too since that picture looks like it was taken in a fluorescent light box. The light in these is very diffuse and being fluorescent can make sapphires look pallid. Taken under the right kind of lighting I think that ring would make your head spin

But it does make me extra critical of photos because I simply can't imagine Sotheby's would put a gem so defective into a "Magnificent Jewels" auction in Switzerland, where the most knowledgeable people attend, and further, that somebody'd pay that much for it. So it must be a much better sapphire IRL than it photographs. Sigh!

The stone is not defective, the picture is. This an excellent example of an image which is not designed to show the better points of this piece, meaning that this picture will not sell this ring. The ring did sell though, so as you say, it must have been much better in person.

You should be VERY critical of pictures. They are too easy to manipulate and should only be used in conjunction with price and a sellers reputation to give a VERY vague idea of whether a gem is worth looking at. I've seen a number of pictures of stones come up on this forum which were highly criticized but which that I thought were really nice stones. If you consider the possibility of a slight pavilion recut and modest initial prices, some of the stones that get a royal beating on here are in reality fine bargains.

How do you tell a frog from a potential prince? Easy, get not only a top view, but at least one side view. From the side view you can easily tell if the angles are decent and what would be required to massage a marginal stone into a great stone.

Thanks for posting this Michael E., it was very informative. I feel as though I learned a lot being able to switch back and forth between your comments and the actual photos JewelFreak had posted.

 

[Michael_E]

Here I "fixed" Southeby's sapphire for them. Is it worth it now? What does it really look like? Oh, I just thought that I'd edit this to say that this was done as a humorous deal. We could change this stone into an emerald if anyone would prefer an emerald.

 

[chrono]

Michael,
I’ve never heard of saturation described as being dark. A dark tone, yes, but not saturation; perhaps this is what you meant? Saturation usually ranges from weak to vivid.

 

[LD]

JewelFreak

Just to summarise

- to know if what you're seeing is a window or not you must look at the gemstone straight on. Not rotated in any direction. If you can see what looks like a hole, what appears to be less facets or a lighter area in the middle, it's probably a window.

- a tilt window only shows when the gemstone is looked at from an angle. This is NOT a window. This shows on many gemstones.

That's the difference between your photo and OUPears.

Hope that helps.

 

[Michael_E]

Sorry for the imprecise language Chrono. Yes, I was combining the two. What I meant was that the overall look of the stone will be on the dark side. This would equate to a slightly dark, medium tone and a vivid saturation. My concern with the image as it's shown is that there are areas which are white. I reality this can't happen, so the effect is probably due to very bright lighting and image manipulation in which the stone has had it's contrast increased to the point that the brightest reflections which should be a lighter shade of green have turned white.

This comment does NOT mean that I think that the stone will be unattractive. I think that it will be a very fine stone indeed. The point is that the picture of the stone is not to be trusted and that a person buying expensive stones is better served by asking questions of a seller who they trust and believing what the seller says over what any image shows. All reputable sellers are going to be honest in their descriptions because they really don't want the stone coming back.

 

[Michael_E]

- a tilt window only shows when the gemstone is looked at from an angle. This is NOT a window. This shows on many gemstones.

Another little tip is that the sort of window that you don't want, always has the basic shape of the stone. If the stone is a rectangle then the window may be rectangular, or more rounded and oval, but it will occur on both sides of the centerline of the stone. A tilt window will only show on the one half of the stone which is tilted up, and will always be somewhat triangular or tapered. This is because the stone's pavilion tapers from the culet area to a wider area at the girdle making the outline of the tilt window tapered upwards as well.

 

[chrono]

Michael,
I do not claim to be a “picture reader” or anything even remotely close but I’ve always thought that the white parts are some sort of camera/flash glare?

 

[OUpearlgirl]

Jewelfreak, when I purchased my tsav I was aware that it may have a small window as well. In the video it did not appear to have one, but the photos look like it does. I figured I would wait until the stone came to see how I felt about it. I think the people that did comment on my stone were just being polite by not mentioning the window.

For the record, I think your stone is gorgeous. If you get it and love it, keep it. Window or not, part of what I love about colored stones is that beauty is in the eye of the beholder.

 

[Michael_E]

Michael,
I do not claim to be a “picture reader” or anything even remotely close but I’ve always thought that the white parts are some sort of camera/flash glare?

Well you do a pretty good job of it, so you're better than remotely close I'd say. As for flash, it can only happen on crown facets obviously and yes, it does happen. When you see those same bright flash areas in places that can not come from the crown, then you know that you're seeing contrast manipulation. I have marked some ares on the initial image which shows bright effects that can not come from the crown. The one on the far left is under a crown facet which is a bit brighter than the rest of the crown and if the bright flash were coming from there it would encompass some portion of that facet and not one spot in the interior of that facet. The other two marked areas on this image are under the table and in small spots only. If they were flash from the table, they would encompass some portion of the table and not just spots, (since the table is flat, anything reflected must show the shape of the light source over a portion of the table and not the shape of an underlying pavilion facet, which in this case should be a medium green).

I'm not much of a picture reader either Chrono. When I look at these pictures I'm using my "cutting eyes" and picking out areas which just don't look as they should. When cutting stones it's really important to be able to see the surface you're cutting. If you get fooled by reflections and bright areas from places on the stone which are not being cut, you can really mess things up quickly. White reflections, in spots, under the table are just impossible in anything other than a very light stone, (saturation and tone combined ), and so the image must have been manipulated.

 

[billyboo]

Michael, Bravo my good man, Bravo. Excellent responses and very educational information.

 

[chrono]

Michael,
Thanks for pointing out those specific areas with red arrows. It helps a lot in seeing that while reading your post. You are correct that those cannot be flash because they are not on the crown facets and it just cannot happen anywhere else except the crown.

 

[Jeffrey Hunt]

Hi Michael,

My humble guess to what's going on with the white areas on the pavilion is that the seller was trying to produce what is generally referred to as the knockout look - an all white background. The knockout photo is a very popular commercial photo convention used quite a bit on ebay and elsewhere, sometimes quite successfully, sometimes not. Personally i think the knockout look is best use is print media, but that's just me.

The stone may have been shot on a white background and once shot the image adjusted to increase contrast to shift a grey looking background to white. This brings the lighter parts of the stone along with it. I would guess it's a simple production shortcut for someone taking many photos.

Regards!

Jeffrey Hunt

 

[JewelFreak]

Michael & everybody else,

There's a whole course here! Holy cow, I need to read this a few times. Great info & thanks a lot.

I'm wondering, Michael, why every colored stone has a window? Impossibility of cutting so light doesn't leak somewhere, even if it's a tiny one? On a well cut gem, is there a particular area where you'd expect to see it -- I suppose that would depend on shape, angles & the makeup of the gem itself, no? Just asking out of curiosity -- this doesn't relate to photos.

Really interesting stuff about photo manipulation too, Michael & Jeffrey. Gives good hints on what to look for.

OuPeargirl, no upset here on anything anybody said about the tsav I ordered! Or any other stone, for that matter, in the future. My questions really were concerned w/how to interpret pictures. It is, as you said, in the eye of the beholder -- if it has a window that drives me crazy, or if the color isn't what I want, it'll trot back to its original home. No big deal. But thanks for your input.

--- Laurie

 

[Michael_E]

I'm wondering, Michael, why every colored stone has a window? Impossibility of cutting so light doesn't leak somewhere, even if it's a tiny one? On a well cut gem, is there a particular area where you'd expect to see it -- I suppose that would depend on shape, angles & the makeup of the gem itself, no? Just asking out of curiosity -- this doesn't relate to photos.

Laurie,
There are two type of windows. The one which is a concern is caused by a pavilion which is too flat or too steep, usually too shallow, around the culet. The problem with this is not that you can see through it, but that there are no flashes from that area and it's right in the middle of the stone. The upside is that if the window is small and the angles are close to being good, then 1/2 of that area will flash as the stone is tilted and the window becomes hard to see. Basically no window is best, a small window, especially in expensive stones of excellent color, are acceptable and big windows are considered lower in quality and value, though still acceptable in some stones, (after all cabs are big curved windows and some of those have very high values).

The second type of window is a "tilt window". This is unavoidable and starts as small, dark, triangular window under the table on one half of the stone, as the stone is tilted. The amount of tilt depends upon the R.I. and critical angle of the stone. If the stone has a critical angle of 34 degrees and the pavilion mains are cut at 39 degrees, then you can tilt the stone 5 degrees before that pavilion main facet on the low side of the tilt, ( side away from your eyes), hits the critical angle and you can see through it. As you tilt the stone more, the other facets around that first one become open and the window grows. This is only the view through the table, you will continue to see sparkle and flash through the other crown facets until the stone is titled very dramatically. This windowing is not really all that distracting and the only way to effectively combat it is to make the table smaller, since that just makes the tilt window smaller. The downside of making the table smaller is that it also reduces the angles of the crown facets and requires a higher crown to get those angles back to optimum. If the rough is expensive it can be very hard to justify cutting this way since it makes the face up size of the stone smaller and so less salable in most areas of the world. That brings us back the the cost/performance trade off.

Is a window or a tilt window bad? Well it all depends. In a modestly priced stone with rough available to cut the finest cut there's really not much reason to cut stones with frontal windows and they should even be designed with small tables and tall crowns to reduce the tilt windowing. For a large expensive sapphire or ruby...well it would be nice to have it perfectly cut, but if the rough doesn't support that I would definitely rather have a largish window than chop it into a bunch of small perfectly cut stones.

 

[PrecisionGem]

Jeff and Mike, don't you think the white area's are just hot spots in the image that overloaded the sensor of the camera, and therefore are way over exposed? I see this all the time when taking pictures. It doesn't necessarily need to be a reflection of a crown facet.
I do think removing the backgrounds from the images makes it very hard to get a feel for how light or dark the stone is, and allows the photographer to make adjustments to the image much easier with out these adjustments being apparent in the rest of the photograph.
To me, the image does look like it's been manipulated, but then green stones are very hard to photograph well in my experience.

 

[StonieGrl]

I always read these threads, always learn from them, but the primary lesson learned is know whom you are buying from and be clear on the return policy BEFORE you put your money down, pay with plastic for recourse if necessary, just in case the stone IRL is not what you hoped it would be.

I stick to spending my money with vendors who have gained my trust, appreciation, and repeat business via quality products and ethical business practices. Yes, I took the GIA coursework in diamonds and colored stones so that I could buy with some confidence or at least know when the waters are murky, but over time I have seen that the biz of diamonds, gemstones, and jewelry has the same spectrum of hucksters, thieves, and con artists that can probably get a leg up on me and it just makes sense to stick with the vendors I know/love.

But I get it that having knowledge can help provide parameters for price charged or value and an appropriate bargaining position if you're into that.

 

[Jeffrey Hunt]

don't you think the white area's are just hot spots in the image that overloaded the sensor of the camera, and therefore are way over exposed?

Hi Gene, I think you hit on another perfect plausible cause of what is happening in the photo.

Green used to be treacherous for me too, now I'm finding pale yellow even harder to shoot, that, and gems that are not precision cut.

Jeff

 

[PrecisionGem]

Jeff, your photo's are fantastic, I especially liked the ones you shot in Africa this year with Roger. I'm leery to travel with my best camera, but I think next time I go I'll take the new Nikon and lenses, and spend some time on a safari.

Gems have got to be one of the hardest things to photograph.

 

[digitaldevo]

Bright spots are NOT signs of contrast manipulation at all. They can be flash reflections, light reflections, what is known as blown highlights or clipping, etc. A digital camera's sensor only has so much dynamic range, the amount of detail captured from dark to light. Anything below the DR of the camera will be black, anything above it will be white. This is the entire reason photographers choose different cameras, there are crop sensor, P&S, full frame, medium format, they all have differing DR, even amongst their own class of camera. You also have to remember the most common sensor used in cameras is based on the Bayer technology. This sensor only captures a single color of the three RGB colors per pixel and then interpolates the other two colors from the surrounding pixels. Interpolation means the camera uses software built in to make up or guess the missing data. So this also tend to affect images, more so in the red and blue colors. This is even why some cameras will show purple as blue under certain lighting conditions even. Other then the Bayer sensor there is the Fuji SuperCCD that is only used in Fuji cameras and the FoveonX3 which is typically used in scientific photo equipment due to it actually capturing true accurate colors. The FoveonX3 uses the same basic principle as film emulsion did, it uses three separate layers on the sensor each capturing one of the three colors, RGB, and does not interpolate any data at all. But currently the only digital cameras using the FoveonX3 sensors are the Sigma brand dSLRs and hybrid DP series Sigmas.

Blown highlights or clipping can also occur simply due to improper exposure or high contrast areas even. You will also tend to see color outlines around these clipped areas caused by what is known as chromatic aberrations(CA) in the form of purple, blue, or green fringing.

They can also be simply caused by too much light or too little diffusion of the light source(s).

Also, there is absolutely NO such thing as a non-edited digital photograph. ALL cameras edit the image in camera to some extent adding sharpness, contrast, saturation, etc. In some models this amount is controllable. But being considering data is made from nothing in most cameras, the image is edited to an extent regardless of settings.

It also depends on the software being used. Some use different algorithms for resizing of the images for the internet. Different algorithms do different things during resizing, anything from sharpness to contrast to local contrast. In most cases what is known as local contrast is lost during resizing of images and in order to keep it true to what was captured one must actually use a USM(unsharp mask) or curves to replace the lost local contrast(which is perceived by the human eye as sharpness but in reality is not even close) or the image could appear slightly fuzzy or even blurry. Of course the better the focus and lens, the better the image will be even after resizing.

Also, P&S(point and shoot aka. all in ones) tend to edit more in camera then a dSLR(digital SLR). And then there are recording formats and color spaces, which I will not even get into unless someone really wants to know, lol.

The lens being used to take the photo is also a large important part. Different lenses have different contrast, sharpness, and even color reproduction capabilities. Some cheaper lenses can be extremely soft and almost put a haze to the entire image even. Some cheaper lenses can add a color cast to the image, which in turn alters the natural colors even more then the interpolation of color data. Some just lack overall contrast and/or local contrast in general. This is most often seen in cheaper consumer grade lenses for dSLRs and cheaper low quality P&S type cameras. But some lenses are almost too sharp and/or contrasty as well.

Since gemstones are graded on white backgrounds with full spectrum lighting, I am a firm believer that at least one of the images for selling a stone should be on a white background. Is this the most artistic or flattering? No, but a flattering and artistic image is not typically reality, which is why I think if one is to use the later they should supply the prior as well. The reason this is done is because different colors can enhance saturation, color tone, and even hide inclusions. A prime example is an old trick vendors used to do while you were sitting right there in front of them, they would show you rubies on a slightly yellow parcel paper of background instead of white, this is because yellow will greatly enhance the ruby, due to the red color. The TV shows use this same technique all the time, example, showing tanzanite on the maroon backgrounds, this is because the maroon color will deepen the tone and saturation of the blue/purple tanzanite. Just like showing an amethyst on a purple flower or backdrop, it will cause the purple to be drawn in from the background and make the stone look more appealing. The same principle can be used with lighting, for example, a common tactic used on Ebay to show color change gemstones that change to red is to use a slightly reddish to a plain red light to illuminate the gemstone in order to greatly enhance the color change. Another technique is back lighting a gemstone, or shooting on a mirror even(not always a bad thing though, it all depends how your lighting is setup if it is bad or not) so as to lighten the saturation and make a very dark stone looks much more appealing.

Colors can also be affected by an incorrect white balance setting as well. This is one of the most common issues/causes.

When shooting a stone the light should be reflected into the crown/table of the stone, as it would be in a setting. Of course some will get in the sides and so forth. You just don;t want back lighting or under lighting. One also needs to be careful of the surroundings as the stones will pull in colors and such from their surroundings and misrepresent the stone. Hence the white backgrounds and bases and why gemstones, especially diamonds, are graded on white. It also helps to shoot a stone table down so the pavilion is visible IMO.

Some will tell you if you see a color cast on the base the stone is shot this means it was enhanced, this is also incorrect. This can be as easily caused by light leakage as it can from enhancement. Some will say pixelation or artifacts means enhancement, this again is not correct, as this can be caused by JPEG algorithms or resizing algorithms or in camera sharpening just as easily, not to mention JPEG compression setting chosen plays a large part in this as many choose lower levels for higher compression so images take up less space and load faster since believe it or not many folks still use dial-up internet or low speeds and don;t like to wait for large files to load.

There are tricks to tell, most easily by loading the image in Photoshop and viewing it under like 1600x magnification and looking for certain artifacts. One of the methods used by forensics. Sometimes it just is not possible, although there is a company working on algorithms to identify edited digital images to verify there legitimacy. But even because "editing" is found, this does not automatically mean "bad" at all. Sometimes editing is just needed to adjust a color shift and make it truer to realism. Many manipulations can simply be done when shooting the gemstone as easily, some more easily, as they can be in editing. As long as editing is done to make more realistic to life (what the eyes see) there really is not an issue. It is when enhancements are done to misrepresent a stone that causes the problems. As already mentioned, most legit vendors are not going to artificially enhance an image to misrepresent a stone, because they don;t want to have to deal with lots of returns, easier to represent it as true as possible from the git go.

Gene, yes, gemstones are one of the more difficult things to shoot! But not quite as difficult as using high magnification trying to chase after a live moving insect and still get the lighting right, lmao!

 

[T L]

Wow, what an informative thread!!

 

[Michael_E]

Sure, it could be over exposure, or even the cameras sensor being overwhelmed. But isn't the end result is the same when looking at these pictures? My point is not a complaint about image manipulation, but that when one sees evidence of over exposure, or contrast differences of this magnitude, that the entire stone is going to be seeing these effects and not just a few spots. The basic conclusion to be drawn, in my opinion, is that the entire stone will be darker when in hand than it appears in the image. Is that incorrect?

 

[Michael_E]

Since gemstones are graded on white backgrounds with full spectrum lighting, I am a firm believer that at least one of the images for selling a stone should be on a white background.

Taking images of gems on a white background is not something that you will find too many sellers willing to do, myself included. At least for myself, white backgrounds make those difficulties that you've mentioned with digital cameras almost impossible to control, particularly with darker stones. It must have something to do with the contrast difference between the stone and background or even which part of the shot the camera is gauging the white balance against, but I can't take a shot on a white background and have it come anywhere close to reality. Even on gray backgrounds it is difficult and I would have to admit that I manipulate every picture that I take. There's just no other way to make them come out looking like they really do. I don't think that it's necessary to examine any gem pictures to tell if they've been manipulated, because you can realistically assume that they all have. The big question is whether the manipulation was done to make the image closer to reality or whether it was done to make the stone in image more salable, but farther from reality. That's easy to determine, get the stone and look at it. Enough people buying from different vendors and very shortly one develops a very good idea of who is doing what.