Lets talk about gemstones

[Hendarion]

Hi.

Lately I was making some graphics for a computer game of mine and I realized that "gemstone look" is actually different to how they are painted on miniatures. So I checked upon some movies (actually Babylon 5, because Londo Mollari always had huge gems on him) and indeed it confirmed my thoughts.
So here's what a polished, non-faceted gemstone in "real" does look (just that its a digital drawing):

Mini-painters are used to paint them that way:

Now... why is that? A gemstone in real has only a very small bright area in the lower region that looks more like a bright circle, with a dark aura in the upper area while a typical mini-gemstone has a bright aura in the entire lower area and a dark circle in the upper.
Is it easier to paint? Does it give a better visual result? Or why we all paint them the same way, that isn't like nature at all?

 

[heniosha]

Im so used to seeing them the 'mini' way that the bottom one looks 'right' to me! I'll have your version and see how goes.

Thanks

 

[Einion]

So here's what a polished, non-faceted gemstone in "real" does look (just that its a digital drawing):

That's what it can look like, it presumes a certain cut/polish - if a cabochon is deeper or more shallow the interior highlight is different shapes and sizes (plus it depends on the refractive index of the mineral). You've also done one specular highlight, which presumes a single lightsource.

The reflection on the upper face is usually left out and my guess for why is simply because it's the style to do this, which may have at its core a perpetuation of the way it was first done. It is also technically easier to not paint this, which may also have something to do with it!

Einion

 

[Hendarion]

Well, the specular of course isn't the main thing I ment, but the fact that the lighting is more centered in real and the edges are darker while on minis the edges are entirely bright. The white gloss though might indeed not be easy to paint as a flat surface.

 

[Einion]

Check these out:

http://geology.com/minerals/photos/kyanite-cabochons.jpg
http://www.rhyansdesignstudio.com/wp-content/uploads/2009/08/Sterling-cuff-bracelet.jpg
http://www.gemsbiz.com/Images/store3/26766.jpg
http://www.gemsbiz.com/Images/store5/92000.jpg
http://www.gemsbiz.com/Images/store3/30044.jpg
http://www.justgemstones.com/citrine_cab_oval.jpg
http://www.gemselect.com/photos/topaz-gem-261356a.jpg

Einion

 

[Jericho]

I think the more common variant to the "mini method" is to have the brightest hilight inside the edge of the gem, and extend the darker/black area to the edge. I don't hilight all the way to the edge, that's for sure! Anyway I think the specular hilight is left out to ensure high contrast on the hot spots.

 

[MRickwood]

Honestly, I thought it was a preference of taste. Some people paint them as they see them. Years ago, McVey showed everyone in the world how he paints gems in White Dwarf I know that's how I learned to paint them. So I have to agree the 'mini' way seems right for me.

I will have to try and do the 'natural' way one of the these days.

 

[Hendarion]

Yea, Einion, I've seen lots of those. But as I spoke of non-faceted. Of course the material we are mostly painted is of a clear color (too hard elsewise actually). Especially your last link is rather interesting, since its nearly exactly the pattern we are used to paint.
I don't remember which episode I saw which clearly looked the other way I posted, but here is a shot at all. See the gem below his chin? In other perspectives the "bright circle" is better in shape, while I also have to say that after some more inspection, the typical mini-gem-style exists ALSO in the same jewel. Just the point of view has to be way more side-looking than rather frontal.

So I guess both ways are correct, but in computer-design the bright-circle-style looks more real due to the flat point of view. Maybe a mix between both shapes would get the closest to "a typical real-life gem seen from an average point of view".

Still... I'm interested how both ways would look on a mini and wanna know if both methods are practical at all, since the "gray" reflection part can be tricky I think - I mean to make a wet blended white layer that has all the same transparency and doesn't obviously show brush-strokes.

MRickwood, show us your results after you tried.

 

[Tee999]

Einion
great examples of gems there. Thanks added to bookmarks for reference material.

Tee

 

[Shawn R. L.]

A trick I've been playing with is putting a focused light spot that the gem casts on the shadow side.

 

[Tercha]

How a gemstone looks depends entirely on how it is lit, the main thing is to be consistant across the miniature.

 

[Hendarion]

Not really, no. Since the direction of the light obviously affects the look really that big, then different gems on different positions with different orientations should receive a different shading. But that probably goes way too far on a miniature than what is worth the effort, especially since many people won't be aware of these changes and would question why the look differs so much from gem to gem.

 

[Einion]

Not really, no. Since the direction of the light obviously affects the look really that big, then different gems on different positions with different orientations should receive a different shading.

That's an excellent point, they should vary depending on their position in relation to the direction the imagined light is coming from. In an extreme case a gem might be on the underside/underslope of something so wouldn't be lit directly at all, only getting a little side light.

But that probably goes way too far on a miniature than what is worth the effort...

I can't think of any specific examples that I could go and look for in the galleries but I think some mini painters do take position and orientation into account for their painted gems, with smaller speculars and not-so-bright interior highlights. That's what I'd do, just as if I were painting the highlights on two buckles, one facing upwards and the other downwards.

BTW a technical detail for anyone that doesn't know it: in high-quality gemstone settings the base of the cup of metal that a gem sits in is often textured to reflect as much light as possible out through the stone. If that's not done the interior of dark stones like blue sapphires and rubies can appear nearly black, even if it's polished perfectly.

Einion