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Wally's Mom
07-13-2001, 12:39 PM
Hi Everybody,

I'm new here, so just a little bit of background: I have been painting for 1-1.5 years, but really just teaching myself through reading everything
I can get my hands on and trial and error. Over the past 1+ years I have accumulated 10-20 different tubes of paint, in 3 brands, a total of 5 "lines". I am starting to understand why different people like (or dislike) certain brands.

But the question I have today -- I'm sure I'll have another one tomorrow.:rolleyes: is: Does everyone prefer the true Cadmiums, or do some "professionals" really use the "Hues" ? The impression I've gotten is that the "Student grade paints" tend to have hues, where the "professional grade paints" don't, but I don't know if this is true.

Also, is "permanent" in the name also a clue that it contains some non-traditional ingredients ? ("Permanent Sap Green" Vs. Sap Green)

Are there any other words that I should look out for in picking new colors (or brands)?

cuttlefish
07-13-2001, 06:51 PM
Cadmium is a semi-precious heavy metal, being both expensive and toxic, though not quite so immediately deadly as mercury or lead. Colors labeled "Cadmium (insert color here) Hue" are mixtures of less expensive, less toxic modern synthetic organic pigments intended to immitate the original cadmium (or other expensive (cobalt) or unstable (alizarin crimson) ) color. At full strength they do this well, but their tinting, staining, and transparency properties are unpredictable. The pigments are intentionally inferior only in student or craft grade paints to reduce cost. Artists formulations are fine, often superior as far as permanency is concerned, but you'd be better off to look at the fine print on the label and learn how to use the colors listed in the mixture on their own.

Patrick1
07-13-2001, 07:20 PM
Safety issues aside, I prefer the colors and opacity of true cadmiums. But for health and cost concerns, I use hues now. If the hue matches the characteristics of the real cadmiun color it's emulating, I doubt you'd ever be able to tell the diference. Now there are some bad 'hues' out there, but the good ones look virtually identical, or even identcal.

You're right that student grade lines will usually contain synthetic hues, while the upscale lines will often contain the real thing, and sometimes also the hues. This is beacue the cadmium 'hue' pigments are usually less expensive.

Yes, permanent usually means more modern, more lightfast pigments. Sap green was originally made from unripe buckthorn berries. It's now usually phthalocyanine green plus some other pigements. The original one faded badly.

Here's some things I noticed:

-Liquitex High-Viscosity cad. yellow light hue
(bismuth vanadate...PY184) is a good sustitute, very similar to the real thing. But it's not cheap.

-I was disappointed with the color intensity of Liquitex Basics cad. orange hue

-Golden Heavy Body acrylics has some good cadmium
substitutes:

-hansa yellow opaque is very similar to cad. yellow medium, only a little less opaque.
-cad. yellow medium hue looks the same but I don't know its opacity

-pyrrole oranges and reds are very good too,
but their pyrrole orange is a little more reddish than real cad. orange, which you may or may not like (I prefer the hue of the real thing). And pyrrole colors are expensive.

Patrick.

Patrick1
07-13-2001, 07:23 PM
I forgot to mention that some synthetic hues have a color shift when mixed with white. But this doesn't bother me a whole lot.

Einion
07-13-2001, 11:53 PM
Firstly, in case you didn’t spot it <A HREF=http://www.wetcanvas.com/forums/showthread.php?s=&threadid=13483>this</A> thread on favourite brands has numerous posts which you might like to check out. Glad to see you’re leaning the characters of the various paint brands you’ve tried, this is the first step in deciding what you want to look for when you try a new paint - some people prefer a stiffer paint similar to oils, some like the liquid acrylics - it’s mostly a matter of personal taste rather than right/wrong so decide what you like and buy accordingly.

You’re essentially correct, one tends to see ‘hues’ in student ranges as they are cheaper pigments used instead of the costly real pigment implied in the name. I think the term Hue in paint names should be replaced with imitation just so everyone is under no illusions about what it means! You will see some hues in artists’ ranges too however - Liquitex is a good example of this - usually to provide a more cost-effective palette for those on a budget. These are not necessarily bad paints, they can use very reliable pigments, but it is highly unlikely you will find one that mimics the true nature of the imitated piment: even if it looks the same when you squeeze some out (its masstone) they very rarely have the same opacity and their undercolour (the subtle character you see in tints with white or in glazes) is never exactly right. If you are not used to the true pigment this may not matter though, as it is mostly the expectation of someone who knows what they are missing that is the issue here, assuming a lightfast alternative.

Personally I prefer the true cadmium colours. They are some of the best examples in their hue positions producing arguably the best warm yellows, oranges and reds, with good opacity and superb lightfastness. Cadmium Yellow Light and Cadmium Red Light are two of the cornerstone colours on my palette and I would hate to have to do without them. As for their toxicity, it is not as great as some would have it and in general use, especially in acrylics, it’s not an issue.

‘Permanent’ generally indicates the use of a non-traditional ingredient, yes. However this does not mean the colour actually is permanent! All decent paints, artist or student grade, should list the actual pigments used and their Colour Index Number on the tube (and if they don’t, like Rowney’s acrylics, don’t touch them) and you should use these as a guide to the lightfastness of the paint if you’re interested in it.

Unfortunately paint names have a long history with many traditional and proprietary names (Rose Dore Madder Lake Antique Extra is the best example of this I know of) being used instead of accurate pigment-based names and even today makers (Old Holland comes to mind as the worst offender here*) insist on using their own peculiar vocabularies to describe their products, most of which are nothing but marketing twaddle! Acrylic ranges tend to be spared these excesses but they are not immune - Monestial Blue instead of Phthalocyanine Blue is a good example. You would be well advised to learn about the best pigments, both modern and traditional, their numbers and then look for these on tubes when you buy, they are the best indicators of the quality of the pigment used.

Hope this helps,
Einion

* ‘Lake’ supposedly means transparent, ‘extra’ is used instead of hue and ‘antique’ means whatever they think it means.