Yep, Circles seem to be my new Square

Last autumn, I was invited to join a new virtual artist group – Artburst Studios – and participate in their inaugural online exhibit coming up February 23-25, 2023 (visit Artburst Studios Website).

I’m quite excited about this group for many reasons – mainly because I’ve come to highly respect the founders and their approach to launching Artburst Studios and all of the detailed ways they’re doing it right.

But, it has also forever changed my abstractions. The way I paint shapes and colors “in my head” when not in my studio. The focus I’ve had for nearly 20 years on painting squares and stripes – lots of linear shapes and corners and sharp edges.

The theme for Artburst Studios exhibit is “Inside, Outside, Upside Down”. So for the past several months, I’ve embraced this by turning my square and stripe shapes “upside down” and painting… CIRCLES!

I quickly found circles to be a “perfect” shape to explore… just like squares. While I continue to use some of my favorite, self-discovered abstract painting techniques, my biggest challenge was how to paint circle shapes that I loved. I wanted perfect round shapes with some rough/irregular lines, giving me a break from some of the crisp, sharp edges of my square past.

So, here’s a few snapshots of how I paint my circles using an unexpected painting tool – PVC pipe connectors and caps! I’ve collected a variety of sizes (even ordering an 8″ cap online since Home Depot didn’t carry caps that large). I’ve sanded the edges of the PVC a bit, but they otherwise work great as is to create “perfect” circle shapes with lines that are varied and unexpected. More on how I apply oil paint to the PVC and stamp the actual shapes in a future post!

My growing collection of Circle-making tools.
Stamping a Circle.
Fields of Circles – perfectly round with irregular lines.

Dog Days of Summer, 2017…

I think we’re officially into the dog days of summer here in Portland with temps expected to rival our all-time high of 107 this week. Even though it’s summer, this is one of my least-favorite times of the year. Heck, I’m hot if the temperature is above 65!

The good news is that my studio is air-conditioned and cool, so I’ve been working on larger and larger oil-and-metallic-watercolor abstracts. But, I think the psychological effect of the heat outside is impacting my success since I’ve recently failed at two attempts of a 52 x 52 inch original… each has clear process mistakes in them and the overall finished paintings just failed to come together. And, due to my unique process of layering oil paints and metallic watercolors, these aren’t “fixable”.

I must keep trying though, as I must finish a spectacular 52 x 52 inch painting for a special exhibit that starts in September… the dog days are ticking!

My studio set up, ready to start another 52 x 52 inch original!

Record October Rains Helped Me Paint This

I love my art-making process – it’s my favorite part of being an artist. And, I’ve worked for more than 12 years now to hone the processes I use to make art.

We had record October rain here in Portland. I thought alot about my process as the rain came down and I painted several new originals for my Pacific Rains Series. You might have noticed that I now mount my original paintings onto “cradled” wood panels. I love both the process and the finished result and have shared snapshots of both below.

After mounting my paper “canvas” onto panel, I’m ready to trim the edges.

“Through The Forest”, oil and metallic watercolor, 30 x 30 inches, SOLD.

All original paintings on my website are mounted on panel like this with crisp, finished
edges. Check out what’s available to add to your collection
by clicking here ==>

Winter Aspens: Making Oil and Watercolor Mix

I’m continuing my quest to master mixing oil and watercolors successfully and just might have a new series emerging: winter aspens. Or winter birch. I’m a bit torn since I love the aspen trees of my native Colorado in winter, but also love the birch found in the Pacific Northwest where I’ve spent many months painting in the winter over the last decade (and now live).

Here are two of my most recent winter trees – layers of oil paint (I use oil sticks such as Winsor & Newton Oilbars), followed by layers of watercolor paint (some traditional paints along with my own mix of metallic pigment powders).  At just the right time, I scrape the tree shapes out with an old favorite tool: pieces of cut up credit cards.

I’m loving these early results… what do you think?

“Winter Aspens No. 3” and “Winter Aspens No. 5”, oil and metallic watercolor, 12 x 12 inches, $350.

Daniel Smith Continues Breaking My Heart…

As a followup to my last post about my crumbling love affair with Daniel Smith paints, I’m sad to say that Daniel Smith has definitely discontinued their entire acrylic paint line.  I’ve primarily used Daniel Smith acrylic paints (along with their watercolor paints) since the “beginning” for me over 10 years ago.  The last time I visited their website to order acrylic, I noticed all of them appearing on web pages that contained “discontinued” in the title.

My acrylic drawer filled with now obsolete Daniel Smith Acrylics.
My acrylic drawer filled with now obsolete Daniel Smith Acrylics.

Well, after a few emails to them, I was told they were discontinued, but they failed to respond with any additional info.  I couldn’t even find an official note from them to their customers and fans (lovers) to explain the what, why, when, etc.

I guess I could go on and on about my breaking heart, but seems I should just move on and start filling up my acrylic drawer with paints that are going to stay around!

Daniel Smith Is Breaking My Heart: The First Time

I’ve long been a huge fan of Daniel Smith paints – so many reasons to love: made in the USA, ultra-fine quality, superb colors… I’ve really been in love since the beginning of my professional art career with my first big order in 2002 of watercolors and acrylics.  I’ve even written several blog posts describing my love, including this post titled “I Heart Daniel Smith” here.

Well, I guess with any such love affair lasting over a decade, there’s bound to be some heartache.  And lately, Daniel Smith is just plain breaking my heart!

Daniel Smith Silver Metallic Watercolor Pigment... now "vintage".
Daniel Smith Silver Metallic Watercolor Pigment… now “vintage”.

I recently discovered that Daniel Smith discontinued one of my favorite products — metallic watercolor dry pigments.  And I’m completely devastated.  Dramatic?  Sure, but I use a variety of metallic paints in most of my paintings – almost all exclusively Daniel Smith products.

I’ve stocked all of the metallic watercolor pigment colors (silver, pale gold, Egyptian gold, copper…) in my studio and have actually been using them rather sparingly over the past several years.  So, now that I’ve started a new Metallic Squares series which requires heavy use of the Daniel Smith metallic watercolor pigments, I went to to order up a bunch, only to discover they aren’t anywhere to be found.  But, oh joy, in an email exchange with one of their Sales people, I was told I could special order the metallic watercolor pigments by the pound, and would I like a price quote?  After putting my heart back in my chest, I replied “absolutely”!

Metallic Squares for my latest watercolor painting series.
Metallic Squares for my latest watercolor painting series.

The next email from Daniel Smith was the first “Dear John” from them.  Apparently after checking with their production team, the Sales person informed me that they had been discontinued “a long time ago” and were no longer available.

Now heartbroken, I’m not sure if I should pursue my love any further with Daniel Smith?  Or should I put my heart back out there with a Canadian lead I have for a new love?

Snip, Snip… Claudia is Ready for Canvas

Well, it took more than a “snip”, but “Claudia’s Jewels” is now cut into 3 pieces and ready to be mounted on my stretched canvas panels.  This painting is on 300lb. watercolor paper, so it’s a bit tough to cut through.  I clamp my straightedge down and use a utility knife (with a fresh blade!) and carefully go for it.

I plan to mount the 3 pieces onto canvas tomorrow, unless the snowstorm we’re promised hits and I don’t make it in!

My latest "jewels" painting (about 44 x 45 inches), cut into 3 for mounting onto stretched canvas panels.

Re-discovering My Scraped Cityscapes

I’ve been busy in my studio lately working on “re-discovering” my feel and technique for mini cityscapes that I once painted many years ago.  The technique for creating these mini paintings is a combo of wash, timing, perspective and a quick hand with scraping shapes.

I first lay down a wash that will give me some good contrasts in the shapes I’ll scrape out while also providing an overall mood to the painting (night/day, winter, foggy, Chicago or New York…).  These go quickly since I have a short time before the wash becomes too dry to successfully scrape shapes.

I’m having a more difficult time re-discovering how to paint these with results I’m happy with than I expected.  Most frustrating seems to be that the pieces of  rigid plastic (like cut-up credit cards… take THAT Chase Bank!) aren’t scraping satisfactorily.  And, it has taken many tries to remember what paper is best (I like 140lb. Fabriano hotpress).  At least in this example, the John Hancock tower is recognizable and I love the rather monotone feel I captured for Chicago (uh, I LOVE Chicago – “monotone” isn’t a bad thing).

What do you think?

Chicagoscape, watercolor, 6 x 6 inches.
Chicagoscape, watercolor, 5 x 5 inches.

I “heart” Daniel Smith…

Well, at least I love Daniel Smith watercolor paints!  Being at the One of a Kind Exhibit in Chicago this past week reminded me of one of the questions I get asked most often, whether in my studio or at an opening or exhibit: “How do I get metallics into my original paintings?”.

Well, Daniel Smith is how.  I think that many people instinctively realize that I’m far from a traditional watercolor painter when they see my originals – just look at my abstract subjects, my unique techniques and my mounted-on-canvas presentation.  And then there are the metallics that I use both subtley and vividly in many of my paintings.  Much of what I do and how I do it is frowned upon by traditional watercolorists.

I’d guess that over 75% of my most-used watercolor paints are Daniel Smith.  His paints are very high quality and his factory colors, including his line of metallic paints, really push the edge.  One of the quirky things I like to list periodically in my studio journal is my current favorite factory colors (colors that are mixed by the factory and come out of the tube ready for direct application or mixing with other colors).  Daniel Smith paints, particularly a few metallic colors, consistently show up on my list, no matter how often I list my current favorite colors.  Here are the top 8 Daniel Smith colors that have been on my lists for several years now (see some sample paintings below):

  • Daniel Smith Moonglow
  • Daniel Smith Indanthrone Blue
  • Daniel Smith Deep Scarlet
  • Daniel Smith Iridescent Copper
  • Daniel Smith Iridescent Sunstone
  • Daniel Smith Undersea Green
  • Daniel Smith Raw Umber Violet
  • Daniel Smith Iridescent Jade

If you are a painter, you simply must try Daniel Smith metallic paints – they are available online at

Detail from “e19”, using Iridescent Sunstone, Goldstone, Copper and Moonglow paints.

“f37”, using Moonglow, Iridescent Copper, Deep Scarlet and Raw Umber Violet paints.

High Plein Air Painting in the Denver Golden Triangle Museum District….

I spent some quality time in the Golden Triangle Museum District over the weekend and today, looking around for the subject of my painting.  There is so much that shouted out “pick me, pick me!”, but I really was drawn to the Denver Central Library building from the southwest side.  I was really looking for some architecture (buildings) with lots of angles (elemental shapes) – the Central Library sure fits the bill.  Check out the reference photo that I’m thinking of using (I picked this out of over 120 photos I took!).

So, my plan was to paint my backwash layers over the weekend and work a bit onsite on Tuesday.  But, after struggling a bit with the size restrictions for this event (100 to 200 square inches, which gave me a 8×18″ paper canvas that I would mount on a 10×20″ stretched canvas), they expanded the size restriction up to 36×48″ today!  So, I’m now thinking of going back to an overall square format – of a bit larger size (maybe 24×24″?).

So, I don’t think I’ll be doing any onsite painting until later in the week… I’ll keep everyone posted, though.

View of the Denver Central Library from underneath the Denver Art Museum “pointy overhang”.

More on my elemental shapes – materials and tools

Continuing on my topic of how I create my elemental shapes with crisp, clean lines…

I’ve experimented alot with different tools and materials over the last 2 years to determine what works the best.  The two keys for me are paper and brushes.

I almost exclusively use Hot Pressed watercolor paper, which has a very smooth, even surface compared to Cold Pressed paper, which is deeply textured and is the paper of choice for most traditional watercolor painters.  The smooth surface of the hot pressed paper allows my elemental shape to set very crisp, defined edges – I think surface tension helps and I posted a bit about that here.  Most of the paper that I use, whether full sheets (22 x 30″) or rolls (51″ x 33′) is Fabriano Artistico Extra White.  I sometimes also use Lanaquarelle, but really prefer Italian-made paper.  I use both 140 lb. and 300 lb. but find that the weight of the 300 lb. paper provides the most stable foundation for a crisp elemental shape.

Brushes are the other tool that I’ve experimented alot with over the years.  I’ve found a few flat/wash brushes to be especially good for creating crisp edges – the Winsor & Newton Sceptre II Gold flat (2″) is one of the best.  I also use Dick Blick Golden Taklon flat brushes (3/4″ and 1″) to paint most of my elementals – they are consistent and inexpensive!

Several of my well-used flat brushes, key for painting crisp elemental shapes!

My definition of an “elemental”

“How do I get such crisp, clean edges on my elemental shapes?”

This has got to be the top question people ask me when visiting me at an event or in my studio.  Just this morning I received an email from an art student in Canada wondering how I get those really crisp, clean lines in my elemental shapes.  So, I thought I’d post here about how I do what I do….

I’ll make this a three-post topic since my key has to do with both materials/tools and technique.  But in this first post, I’ll try defining “elemental”, especially since I made it up and you won’t find my definition in wikipedia!

David Castle’s Elemental:  “A painted shape, usually rectangular or square, that has crisp, defined edges and is created using a variety of brushes on a typically absorbent paper surface”.

Notice I sprinkled a few loose descriptors in there such as “usually” and “typically”.  I think this is because of the nature of my elementals (and one reason I named them that) – they have a kind of organic nature about them.  For example, in my last post, you’ll see some elementals that are certainly not rectangular.  And, I’ve also tried painting a few elementals on non-absorbent surfaces such as Yupo (those sure took a long time to dry!).

I’ve never actually tried to create a descriptive definition of my elementals; but, a picture is worth a thousand definitions, so:

elementals-sample-squares.jpg                not-and-elemental.jpg
These are elementals.                                       These are not.

Any questions?

Monotype workshop with Lauri Lynnxe Murphy

This past weekend I took a monotype printing workshop with Denver artist Lauri Lynnxe Murphy, who also owns and runs Capsule Gallery and Event Center in the Santa Fe Arts District.

WOW!  I have been wanting to get an introduction to monotypes for awhile and loved learning in this workshop.  We had a small group – just four of us – which was really a perfect size.  As a primarily watermedia artist, I was both excited and frustrated to work with oil-based paints and inks – I love experimenting, but the oil-based paints sure behave differently than watercolors/gouache/acrylic.

I was intrigued by how different the process is from my watermedia painting.  Paints/inks are applied to a plexi “plate” with an infinite number of tools and then run through the press to print the image on paper.  I think it is the “running through the press” part that intrigued me.  Introducing such a machine into my creative process since it applies a bit of the unknown to the final result is pretty cool (well, as a beginner, it applied ALOT of the unknown to my images!).  Loved it and will be doing it again… check out one of my monotypes below.

It was also a big bonus to get to work with Lauri – I’ve bumped into her a few times around the art world and really appreciate her contributions.  I believe she plans to have additional workshops in the future – Lauri, how can people reach you if they’re interested?

Monotype workshop in the basement at Capsule.

A few of my first prints… and the press in the background.

Untitled, monotype, 8×5″.

5 Interview Questions from S.L. Peterson: Answer #2 re: music

Question #2:  What kind of music (if any) do you listen to in the studio?

Music is a significant source of inspiration for me while I paint, and I am almost always listening to something while painting (typically on my iPod).  I love quite a range of music – from classical to contemporary Christian to country.  I typically load my iPod with a random playlist from the music on my PC, but also have several “favorites” playlists that I’ll load up when I really want to get into my zone of music that inspires and focuses my painting.  Some of the artists on my favorites playlist are:  Michael W. Smith, HEM, Enya, George Winston, Dido, Alex Grant, Dixie Chicks, Keane and Rufus Wainwright.

I think audio stimulation is fascinating… I know artists that work in silence and at least one who likes watching Jerry Springer while painting!  For me, music helps me focus and get closer to what I’m doing and the different components involved: color, water, air, gravity, paper, brush, rocks….

Mounting (and sealing) my watercolors on canvas – Varnish Update

In my quest for the best methods and materials to use to mount and seal my art, I’ve discovered a new varnish that I like to use for the final finish on my watercolors that I mount on acrylic-embellished canvas.  Liquitex Satin Varnish has a great, light consistency for a final varnish finish and contains a UV filter to protect against UV damage.

I’m currently using this varnish “straight up”, without mixing in any matte varnish because I like the satin balance of gloss and matte.  Here in Denver, Meininger always seems to have this in stock.

Note: Be sure to visit my other post with more details on my canvas-mounting process here!


Purple and Magenta… complete!

In a flurry of activity, I’ve finished the Purple and Magenta commission that I’ve been working on for nearly a month now!  I’ll be hanging it in my clients’ home tomorrow and will post some installation pics sometime soon.  Final finished size of each panel is 50×19″ with an overall size of 50×57″ for the three panels.

Canvas panels (50×19″) getting embellished with acrylic… 

Just needs a final coat of varnish…

I love Surface Tension!

According to Wikipedia, surface tension is an effect within the surface layer of a liquid that causes that layer to behave as an elastic sheet. This effect allows an insect such as the water strider to walk on water. It allows small metal objects such as needles, razor blades, or foil fragments to float on the surface of water.

Well, with some patience, practice and a watchful eye, I use surface tension as one of my favorite watercolor paintings “tools”.  Apparently it is measured in terms of “newtons per meter”… any scientists out there that want to come to my studio to measure one of my paintings in progress??  Any other artists have a surface tension technique to share?

I often use surface tension in my wash puddles to concentrate color in corners.

A view of several puddles using surface tension to concentrate my paints in different areas.

How I seal my watercolors on paper

Many people – collectors and artists alike – have asked me how I seal my watercolor on paper paintings that I then mount on stretched canvas.

An artist friend of mine, Janet Fons (oil pastels), and I both began experimenting with methods for sealing our artwork about a year ago.  Neither of us liked the glass we had to use since it created a such a barrier between the art and the viewer.  We were also just plain tired of dealing with glass (and for me, I was tired of the whole framing idea – it was making me a bit clausterphobic to have my watercolors so entombed).

After much experimenting, here’s how I seal my watercolors:

1.  After I complete a watercolor painting on paper, I seal it with 3-4 coats of Krylon GLOSS UV-Resistant Acrylic Coating.  I don’t like the finish of the MATTE coating (plus, it dulls metallics).  I use light coats and let each dry at least 30 minutes before applying the next coat.


2.  I let the painting dry over night after the last coat of Krylon spray.

3.  Meanwhile, I embellish my stretched canvas with acrylic paint.  I use 1.5″ deep “gallery wrapped” canvas so that I can paint the edges and finish my piece without a frame.  Usually I apply 2-4 light, watery washes to the canvas, often using metallic acrylic paints.  I then add deeper highlights to the canvas edges or corners.

4.  Once my canvas is completely dry, I use Liquitex Fluid Matte Medium to glue the watercolor on paper to the canvas.  I apply the matte medium to both the canvas and paper to help bond them together.  I then (carefully!) turn my canvas over and press on the back of the canvas to remove air bubbles.  I use cut plexiglass and weights to compress the back of the canvas for 1-2 hours.


5.  After removing the weights, I clean up any matte medium that has oozed out around the edges of the paper.  The whole thing then dries overnight.

6.  Finally, I apply 2-3 coats of Liquitex Gloss Varnish Flexible Surface to the entire piece using a soft brush (I use hake brushes), allowing each coat to dry 2-4 hours.  I’ve found my own “formula” achieves the finish I like best – a mixture of about 3/4 Gloss Varnish + 1/4 Matte Medium + a bit of water.  On large pieces, I sometimes spritz the surface with water to help relax the brush strokes.

Some folks have asked me about the archival quality of the process I’ve developed.  I’ve actually corresponded with Krylon and Liquitex about this.  While no one can really say how long acrylic coatings/varnishes will ultimately last, the best information I have is that there should not be any color or surface finish deterioration for 75-100 years.  I can’t imagine that, with proper care, my watercolors mounted on canvas won’t last 2-3 times that long.  I sure want people to enjoy my art at least until we have flying cars and are living on Mars!

The Motherlode!

I’ve started several Elementals since I got settled… here’s one that has a deep metallic back wash with dark elementals in red, blue, purples and indigo:

dsc02282.JPGAgate Beach

But, I’ve also been wanting to start a few Fossils (I paint fossils with smooth rocks that I place in puddles of watercolor and then drop in various colors around it as the puddle dries over 4-36 hours).  I didn’t haul any of my usual rocks out here that I paint with in my studio, knowing that the Oregon beaches, particularly Agate Beach (just a 5 minute walk from my place, through the tunnel) is the Motherlode of painting rocks! 

I’ve been over to Agate Beach every day for the last few days searching for great painting rocks.  After this morning’s trip, I have enough to start some Fossils this afternoon.  Here is a picture from my trip to Agate Beach this morning.


Two of the Blizzard “Fossils”

I’ve been asked how the Fossils that I started before our blizzard here in Denver last week turned out.  I finally got back to my studio today (after almost a week!) and have two of the Fossils below.


These Fossils have 4 washes of watercolor underneath and I used metallic bright gold and antique copper along with indanthrone blue and carbazole violet.  I dropped color around the stone probably 5-6 times before I let it dry.