PR101 and PR102 (Pigment Red 101 and 102) are among my favorite pigments for paint and they come in a large variety of colors. PR102 is a natural red iron oxide (red ochre) and PR101 is the synthetic version. Below is my collection of oil paints using either of these as a single pigment paint with nothing else added. I photographed this in direct sunlight during the afternoon. All of the paints were mixed twice with about an equal 50/50 mix with white.
Old Holland Yellow Ochre Burnt
This is my only natural red ochre in oil paint. As I understand it this pigment is made by roasting natural yellow ochre pigment until it turns reddish. It could make a good alternative to burnt sienna. It’s a little lighter and brighter, and has a stronger color.
Winsor & Newton Transparent Red Ochre
I wasn’t really sure what to expect when I got this because the name sounds like it’d be what’s normally called Transparent Red Oxide, which is the variety of PR101 that W&N already uses in their “Burnt Sienna”, but this is really very different. I think it’s close to the same as the Yellow Ochre Burnt above it but this is a slightly cleaner and more pure color. As the name suggests, this paint is semi transparent. The tinting strength isn’t as overpowering as some of the others in this list so it’s a bit easier to work with. This is one of those paints that I wish I had gotten years ago. It might even be my favorite red ochre.
Rembrandt Burnt Sienna
Although real Burnt Sienna is made from either PBr6 or PBr7, there are a few brands of paint that use a Transparent Red Oxide version of PR101 instead, which has a much stronger color, higher transparency, and higher tinting strength than actual burnt sienna. It doesn’t show up well in the photo but this particular one is lighter in masstone than the “burnt sienna” below it from W&N.
Winsor & Newton Burnt Sienna
A nice example of Transparent Red Oxide. It has good transparency. I tend to prefer paints like this over actual burnt sienna for the greater color strength.
Blue Ridge Transparent Red Oxide
Very similar to the above paint, but not as transparent. This one also seems to have a slightly higher tinting strength, but I can’t guarantee that I got the mix with white an exact 50/50 mix on any of these.
Old Holland English Red
Now we’re getting into the slightly cooler temperature colors for red ochres. This is a very high tinting strength paint, and easily overpowers most other paints that I mix it with unless I use extremely small amounts of this. Because of that, I don’t think I’ll ever run out of this one when you consider how little of it is needed in each paint mix. This one it so similar to the venetian red below that I actually mixed up the labels on the image at first. I’m 99% sure I have it right now since I kept the tubes lined up in the same order that I placed the paint on the palette and because this paint has a thicker, more viscous consistency.
Winsor & Newton Venetian Red
There’s a little bit of variety of colors that are referred to by different brands as “venetian red” but this name is generally given to a semi-cool earth red that’s not as cool as something like an Indian Red.
Blockx Mars Violet
As far as I know this is about as cool as red ochres can get. I bought this one from Blockx because when I looked at a paint chart someone else had made of different brands of mars violet the one from Blockx looked like the coolest. On an earth palette of red and yellow ochres this could be a very useful.
A similar comparison of yellow ochre oil paints can be found here.
Too Much White Paper 
Very informative. I love the red ochre color, too. I think my favorite.
Thanks 🙂
I’ve gotten or made several new natural red ochres since I posted this though. Maybe I’ll post them tomorrow.
edit- I just remembered I’ll have another one as part of an order I placed yesterday, so I’ll wait until that arrives. 🙂
Thank you for this brilliant demonstration of the subtleties of reds. I have been painting a chestnut horse which is most certainly not the colour that chestnut is perceived – leaning instead very much more to the cooler reds and Mars violet and your lovely chart and description has helped me work out what to use without losing that minds eye perception of a rich orange red chestnut!
More like this please!
Janey Osque
I’m glad it helped you. I’ll definitely get more of these comparisons done sometime soon. 🙂
Dumb question perhaps but I’m a beginner. Is there any reason these mixes won’t come out similarly with acrylics?
That’s a pretty good question. The short answer is that yes it should be similar, especially if the acrylic paint is using the same pigment variety as the oil paint. One consideration is that acrylic paint will look lighter while wet and oil paint stays the same.
The longer answer if you want to focus on technical details is that the final appearance may have some differences. Basically, oil paint will have a bit more depth, especially if used transparently, than other media because oil is the best binder for being used transparently. If painted thickly oils and acrylics are close to the same.
If the dried paint has a matte surface (which is very normal for watercolor, for example) it will make darker colors look lighter and less rich. I think acrylic paint tends to be a little more matte than oil paint, though oil paint can vary a lot from one pigment to another.
Different binders can hold more pigment than others, and oil can handle more than acrylic binder, so the same paints in acrylic will be less pigment rich. That’s part of why from one brand a 37ml tube of oil paint may cost more than a 60ml tube of their acrylic. Still, if all the acrylic paint used has proportionally less pigment, I’d assume the mixing between them would actually be about the same in terms of how much lighter a color becomes when a certain amount of white is added.
Just remember the key here is that within each pigment code there can be variations, as seen in this photo. The same paint name can be used as a label for different varieties, depending on what the paint maker chose to use. So you might have an Indian red from one brand that looks similar to the Venetian red in this photo, and an Indian red from another brand that uses the same pigment code but looks closer to the mars violet above.
It’s not something to worry about too much though. It’s too easy to get bogged down in technical details and distracted from just painting. 🙂
eu gostaria de saber qual o melhor amarelo o melhor vermelho e azul para e branco para fazer pintura a oleo de preferencia cores transparentes pois trabalho com camadas, tks
I would like to know what is the best yellow ochre, red, blue and white to make tranparent oil colors
Hi, sorry for the late response. I’ll try to make up for it with a longer answer.
The most transparent yellow and red ochres will be the ones called something like transparent yellow oxide and transparent red oxide. Sometimes you might see one called transparent gold ochre. They have extremely small particle sizes. Unfortunately there don’t seem to be any easily available transparent cool red ochres, which to my understanding is mainly because of the size and shape of particles needed to made red ochre have a cool color.
The most transparent yellow ochre I’ve found is probably a variety of transparent yellow oxide from Charvin that is called Indian yellow deep. Another possibility would be yellow ochre light from Rublev, which uses a very light and weak natural ochre. I don’t have that paint from Rublev, but I’ve made paint from the same pigment they use and it’s an interesting transparent yellow ochre.
Prussian blue, phthalo blue, ultramarine, and indanthrone blue (which is also called anthraquinone or indanthrene blue) are all transparent or semi-transparent blues. Actually, there aren’t any blues that are extremely opaque, unless you look at cobalt teal, which is definitely opaque but more teal than blue. Cerulean blue is semi-opaque and cobalt blue is still less opaque but not transparent. Besides those, there really aren’t many options for blue pigments, and the rest are rarely used.
Personally, I like to mix a little green earth (terra verde) into ultramarine blue to make it less reddish and more of a middle blue, but green earth is extremely transparent and also makes the blue more transparent too.
There’s almost no single blue or blueish pigment used by artists that is an earthy color like the ochres are for yellow and red, but a couple of exceptions would be cobalt turquoise and natural or synthetic indigo.