Transparent Paint?

I think whatever kind of paint you use, add the thinner for that. Put thinner in cup and add drop or drops of color until it looks right, but transparent paints tend to bleed because of the thinner in them.

 

You're welcome

 

Adding clear binder or vehicle is probably better than straight solvent.

Actually, add the paint to that.

 

I don’t think you can make a transparent paint from opaque
totally differnt
Opaque has reflective qualities to cover up underlying items
Transparent let’s light thru showing what’s underneath
Hope this makes sense

 

"Paint is a suspension of tiny colored particles (or powder) within a medium, which might be polymer, oil or alkyd (etc). Different pigments will have particles of different sizes and this will determine how much medium will be needed to make the paint flow. The power of a chosen pigment to cover what is beneath is determined by several factors, namely being:

The size of the pigment particles.

The thickness of the paint layer.

The amount of medium used with the paint.

The refraction indices of the pigment (explained next)"

Pigments aside, there's much that can be manipulated for certain effects.

 

The best I have managed to do was done by adding just a touch of color/paint to clear gloss or flat(thinned for airbrushing). It is not as good as proper "transparent" colors...but can "pass" in some cases.
Outside of paints marketed for taxidermists...check on those marketed to model builders.
Tamiya has a line of transparents (not 100% sure, but I believe they only do acrylics)
Alclad also has transparents (lacquer)...they also have a great variety of metalics.

I use Alclad, ordered through "Sprue Brothers"(online model/hobby shop)

 

Tamiya paints are Acrylic Laquers I believe.

 

yes that would be a better solution than thinner. I don't know why I said thinner. Good catch.

 

transparent paints let the light through to the underlying paper while the opaque paints reflect the light, effectively blocking it and stopping it from reaching the paper. The effect is that transparent paints have a more glowing, three-dimensional finish thanks to the resulting layering, while the opaque paints have a flatter, matt appearance.

Some media such as gouache, chalks and pastels will always be opaque, because the medium itself is opaque.

Other media such as watercolours, oils and acrylics are transparent, so the transparency/opacity of the paint will depend on another factor, which is the pigment used in each colour.

When it comes to transparency, there are 4 categories of pigments:

• Transparent, which let all the light through
• Semi-transparent, which let most of the light through but reflect a small part
• Semi-opaque, which reflect most of the light but let a small amount through
• Opaque, which reflect all the light and let nothing through

Here are some examples of what this means in practice.

Case A – A single wash of transparent blue over white paper

The light goes through the paint, bounces off the paper and comes back through the layer of paint. The eye sees the blue colour, with a bright finish thanks to the brightness of the white paper underneath.

Case B – A single wash of opaque red covers the paper

 

The light bounces off the paint without allowing it to travel through to the white paper. The eye sees the red colour, with a flatter finish because of the lack of depth.

Case C – Three layers of transparent paint over white paper

The light travels through all the layers, bounces off the white paper and comes back through all the layers. The eye sees all the colours at once, with a lot of depth created by the layering.

Case D – One opaque wash of green between two layers of transparent colours

The light goes through the yellow layer to the green opaque layer but cannot go any further. The eye will see the green through the yellow, giving a yellowy green colour with some depth, but the grey layer and the white paper will disappear entirely, limiting that depth and annihilating the white paper-given glow.

Now it’s up to you to play with all the above, combining your pigments to reach your desired effects. Remember that this will only work in a transparent medium. If the medium is opaque, only the top layer will be visible no matter what pigments are used.

Examples of transparent colours: all the Quinacridones and Phthalo colours, Permanent Rose, Gamboge and Indian Yellows, Perylenes and most blacks.

Examples of opaque colours: all the Cadmiums, Cerulean Blue, Naples Yellow and all whites.

Lemon Yellow and Sap Green are the troublemakers. Depending on the brand, some are transparent and some are opaque. I will write about them in the Pigment Spotlight section in different posts.

 

From your research

“Some media such as gouache, chalks and pastels will always be opaque, because the medium itself is opaque.

Other media such as watercolours, oils and acrylics are transparent, so thetransparency/opacity of the paint will depend on another factor, which is the pigment used in each colour.”

Even Opaque pigments are transparent under a microscope. But, they are more refractive than pigments regarded as transparent.

In the conversation of transparent paint, Cadmiums (not just Cadmium hue pigments) which are regarded as opaque pigments are being made and sold in transparent versions.

For fish taxidermy, unless we want to get into some highly technical arguments, add paint to clear binder/vehicle and you likely have an improvement in transparency.

I think OP is looking for this solution rather than a more technical approach requiring actual knowledge of specific pigmentation of fish paints.

 

One day you will learn

 

Fair enough. I hope to. I hope we all do.

There's a lot to this discussion that goes beyond what most need for painting fish and even more that gets into the specifics of individual paints and components therein.

I can't speak to what extenders and other additives are in paints that haven't been named or that I don't use.

I did find the following article to have some interesting data points:
https://www.naturalpigments.com/artist-materials/transparent-opaque-paints/

You'll see carbon black is listed as opaque. It isn't even measured on the refractive index in this report. Now it's possible that reference is to PBk6, however PBk7 measures as a highly opaque pigment that will equal PBk6 in opacity: http://www.artiscreation.com/black.html#PBk7

Yet, we see it in both opaque and transparent forms by a fine art manufacturer.

When transparent binder and pigment formulate paint, adding clear mediums can effect hiding strength and make the mixture perform very different than the original formula.

Is the pigment still opaque, sure, sort of.

 

I see what you got
And most of what you posted is correct
For opaque paints and is dead on
But transparent are produced completely different
In the 70s we all used automotive and acrylic paints
In fact I’m starting to transition to mostly transparent and mix in opaques as needed
Same as a chrome paint I think crab dude elaborated on
A completely differnt critter in its own

test
Take a jar of yellow ochre and a jar of transparent orange
Shake for thirty minutes
Let set for a week
Which one has more settled pigments
In salt water fish you must know the transparent vs the opaque difference to do top end work
And compete in that matter
What I posted earlier is what I show to all the kids I teach in painting fish

 

Look at the diagrams I posted earlier
This is a very simplistic view of the two types

 

I agree...they show a simplistic view.

They demonstrate the properties of opacity vs transparency. That's all.

They have nothing to do with altering hiding power, the ability to do so or not do so, nor should they be misunderstood as a definitive representation of what transparent and opaque pigments can be made to do.

It's simply more complex.

 

You just make it hard
Really it’s simple

 

Nah, I'm not making anything. It's how it works that's more complex.

It's a shame you're not going deeper with your students.