Lemon Ochre Study

A while ago I mixed black or white with lemon ochre to line up in value with Munsell neutrals. Well, that got me thinking about lemons, so I've been carrying a couple around, studying their contained shadows in different lights and angles. I realized that I couldn't accurately portray the shadows only by lowering value--there was simply too much chroma in those low values.

This evening I mixed a fresh batch of each lemon ochre value and then began mixing pretubed Munsell neutrals with corresponding value. See the two piles to the right, how close they are in value.

Here's an example of the chroma range in a light value.

And here is the final study, each highest chroma possible value progressively sliding towards neutral.

Already I can see that the shadows are lining up nicely with a lower chroma. Now I am wondering how many values I could premix to cover a lemon's colors. Fascinating stuff...

I want to complete this study with red and green earths too. I'm imagining all the possible colors without even mixing paints...

Oil Testing

Here's the beginning of a little oil test, nine samples as follows:

The first four from Natural Pigments:

• Aged Linseed Oil
• Pale Grinders Oil (High-Acid Refined Linseed Oil)
• Vacuum-Bodied Oil (Low Viscosity, Linseed)
• Sun-Thickened Aged Linseed Oil (handmade from above oil)

The next five from Jedwards International:

• Cold Pressed Organic Linseed Oil (source oil for washed and reclaimed below)
• Hand-Washed Oil - Batch 1
• Hand-Washed Oil - Batch 2
• Reclaimed Oil
• Safflower Oil

Click image for a better view

Using cotton swabs I dabbed these oils across strips of masonite prepped with GAC 100 and Acrylic Gesso. Once the oils dry I will keep one in the sun, one in the dark. How long will each oil take to dry? Will it yellow, or even lighten, over time? We'll see. I'll be keeping watch and taking notes, presenting results from time to time.

Nesting Time

Yesterday I noticed this Baltimore Oriole, Icterus galbula, intent on a few vines. Today I paid closer attention and realized that she is stripping the bark for nesting material. Every year the orioles return and nest nearby.

Remember a couple of years back when we looked at nesting robins? A pair has nested again under the deck, very close to the previous nest. I could pull up some decking for photos but this year choose to leave well enough alone.

Filtering Oil

While skimming oil for another round of washing there is always a bit left behind. That oil - fatty acid barrier is not always distinct and one must make the decision when to stop and leave the leftovers for later.

The leftovers get dumped into my reclamation oil jar, which was recently washed up a few times and considered done. Only thing is that the result was terribly cloudy, still holding onto those fatty acids and probably some water as well.

I've had this idea mulling about that I could filter this stuff...

The funnel tube is plugged from end to end with a cotton ball. The funnel is friction fit into a piece of corrugated cardboard. Hi tech, huh? ;-) Well, it works so absolutely perfectly well! That cloudy mess is coming out crystal clear!

It is taking time--a few hours to get less than the two ounces you see here, but I see no worries. This looks like one of those set 'em and forget 'em procedures.

OMS

Odorless Mineral Spirits (OMS) is a solvent that oil painters commonly substitute for gum turpentine.

Why not just use turpentine? It's a serious health hazard. Additionally, some people are, or become allergic or sensitized. See this OSHA document for details.

Solvents are used for thinning oil paint, cleaning brushes and as an ingredient of mediums. OMS can handle thinning and cleaning but may not be strong enough for some mediums.

I pulled up the Material Safety Data Sheets (MSDS) for these brands of artists's OMS:

• Weber Turpenoid - Aliphatic Hydrocarbon 100%
• Gamblin Gamsol -  Naptha(Petroleum), Hydrotreated heavy
• Winsor & Newton Sansador - Distillates (Petroleum), Hydrotreated light

They are all quite similar, and even may compare to the OMS you will find in a hardware store. I spent hours Googling these solvents, trying to determine which brand might be safest and still perform.  What I did find for my research was a wealth of misinformation, a good deal of it from large artist's forums. I've come to find reliable information from these web resources:

• http://www.naturalpigments.com/vb/forum.php
• http://www.amien.org/forums/

In this case, AMIEN held the answers. Here are a couple of forum quotes that I used to based my decision:

There are significant differences that make true, highly-refined odorless mineral spirits safer alternatives to turpentine. True odorless mineral spirit has the aromatic component refined out of it – less than .005% remains. Most significantly, OMS has an evaporation rate approximately 3 – 5 times slower than turpentine – this means that during a painting session you will work around less evaporated solvent. In addition, OMS has a high flash point, and is not absorbed into healthy skin. 

http://www.amien.org/forums/showthread.php?2925-odorless-mineral-spirits

. . .

The other factor we will want to consider is the health issue of solvent exposure. You'll find some art store brands to be less toxic than a typical hardware store variety... The following are Threshold Limit Values (TLV) for an 8 hour work day (according to ACGIH). Higher values are LESS toxic.

Turpentine 100ppm (including W&N distilled)
Aliphatic Hydrocarbons 100ppm (Turpenoid, Utrecht Odorless)
Iso-paraffinic Hydrocarbons 171ppm (Maimeri Odorless)
Common hardware store OMS 100-200ppm
Hydro-treated Heavy Naptha 300ppm (includes Gamsol)

Hydro-treated Heavy Naptha at 300ppm will have the minimum of aromatic solvent content and be less toxic, as the AMIEN staff suggested. The art store OMS at 200ppm may have less of the really nasty "impurities" of the common hardware store OMS like 1,2,4-tri methyl benzene at 10ppm.

http://www.amien.org/forums/showthread.php?2004-Hardware-store-OMS

. . .

If you find this interesting, I urge you to follow the links and make your own decisions. Based on my research, I will be soon using Gamsol--my Turpenoid bottle is nearly empty.

Work Continues

I've been in a house cleaning frenzy all week long. The eventual outcome will leave me with a clean and organized home, and a working studio. I am already having an easy time finding art materials!

Today I take break from housework to catch up on a few projects. One block needed cleanup after I mistakenly painted the wrong value on a few cube faces and many blocks needed work from leftover fingerprints. I tried to be a little less sloppy and pay more mind today. :-)

Here's the setup for my first Bargue exercise. I pulled Plate 1 into Photoshop to properly size the images to 18 x 24". I'll be working with the sight size method for copying. I'm using a translucent support so that I can overlay and check my work. More on this later...

And lastly, oil washing continues. I'm testing out inexpensive plastic containers, rather than those glass canning jars that have all cracked. So far so good with the plastic.

Tonal Studies - Block Painting

This evening I began painting with pretubed Munsell values. I botched up the lighting here with  warm overhead fluorescent lighting and front facing balanced lighting--a better photo is coming once I finish up the cubes. I can envision tuning up individual cubes once everything dries but I think I have a reasonable and exciting starting point.

Tonal Studies - Block Prep

The blocks are nearly ready for painting with Munsell neutrals. The initial coats of GAC 100 might have lifted the grain, leaving me to try to smooth things out with sandable gesso. Getting there!

Tonal Studies - Block Making

Ah, such a long overdue project... Finally underway!

I lurk on rationalpainting.org where among many other topics members are encouraged to delve into using Munsell as a base for tonal studies. Rather than try to explain the details, I refer you to the wonderful work of Paul Foxton. Paul is building an art teaching website so be sure to look beyond his posts on tonal studies.

Starting with an eight foot 4x4 cut in half, I ripped it to about 2.5" square. This Freud blade cuts so smoothly that only minimal sanding was needed.

Using a power mitre box, the blocks were cut.

With the blocks cut out, it was time for a couple of coats of Golden GAC 100. I mixed in a bit of water, as I find this primer somewhat thick and seems to leave behind a bit of texture

The blocks are nearly ready for a few coats of Golden acrylic gesso but first I'm letting the GAC 100 get nice and dry. There's still a bit of tackiness here.

Followups

The storm came trough leaving inches or rain behind. Here's the same shot right after but by the next day it was all soaked up. It's the beauty of swampland, regulating flow in the watershed. A sponge that prevents runoff and flooding.

Here's my ground lapis applied with egg tempera. I couldn't resist a bit of a royal touch with W&N gold gouache. Something like twenty layers at its darkest. It's a tiny swatch, only about an inch high.

Finally, some rain

The crabapple blossoms are pulled down, heavy with rain.

My backyard swamp was dry before the rains began. Hoping to see puddling up after the heavy rains come through.

Lapis Continued

After posting last night, I began to wonder about the authenticity of that gemstone. I didn't think to identify the stone prior to grinding it up. (I'm a gemologist in a prior life.) An indication of lazurite is a sensitivity to acids, so I sprinkled a pinch of pigment into white vinegar. Looks good as you can see in the photo; the blue within minutes disappeared. Still, it's only an indication. (By the way, no gemologist would ever conduct a destructive test without prior consent.)

Here's the pigment with linseed mixed with a palette knife.

I plan to pick up some natural untreated lapis chips and give this another try.