Zograscope

A zograscope is an optical device with a large lens that enhances the impression of three-dimensional depth in a flat image.

It was a parlour amusement of the 17th and 18th centuries. According to Wikipedia,

"Some artists from the 17th-century Dutch Golden Age painting, like Pieter Janssens Elinga and Samuel Dirksz van Hoogstraten created a type of peep shows with an illusion of depth perception by manipulating the perspective of the view seen inside, usually the interior of a room. From around 1700 many of such "perspective boxes" or "optica" had a bi-convex lens with a large diameter and small dioptre for an exaggerated perspective, giving a stronger illusion of depth. Most pictures showed architectural and topographical subjects with linear perspectives."

Engraved views with enhanced perspective called vue d'optiques were created for this purpose.

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Vue d'optique and Zograscope on Wikipedia

Thanks, Roberto Quintana

Three Artists Paint Cole's Studio

 

 

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Christopher L. Evans joins me and Jeanette to sketch Thomas Cole's old studio. 

We talk about perspective and keeping brushes clean.

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Christopher Leith Evans website

Jeanette Gurney video "Sketching with Line and Wash"

Thomas Cole Historic Site

Reilly's Perspective Tip

Illustrator Frank Reilly painted this aerial view of a railroad yard. The perspective lines vanish to points far outside the composition's rectangle. How did he locate those points?

Reilly explains that the client wanted a certain number of freight cars to be visible in the shot, which meant he had to use a high point of view. 

He went to the lumber yard and found strips of wood that stood in for the railroad cars, then photographed them from a stepladder, experimenting with different angles.

He took a photo of the wood strips and put a print of the photo in the middle of a large sheet of paper (above) and traced the perspective lines back to all three vanishing points (VP). From each point "he then swung an arc on the paper near the edge of the photographic print." 

He then photographed this diagram and put it in a projector. He was able to trace onto his larger board the main lines of the separate railroad cars and the big arcs that would lead him to the remote VPs. 

"On the enlarged drawing (thumbtacked to a large drawing table), templates cut of thick cardboard were tacked, their curved edges identical with the arcs of the projected enlargement."

"The T-square, traveling along the curved arcs of the templates, served for all converging lines, many of which in addition to those of the photographic print, were needed for the detailed drawing."

"The lower vanishing point is located in a vertical that passes through the vertical lines of the picture quite near its left edge."

From American Artist Magazine, March 1951.

Books

The Frank Reilly School of Art (about Frank Reilly's teaching)
The Student's Guide to Painting by Jack Faragasso (student of Frank Reilly)

Previous blog posts about Frank Reilly 

Art Advice from Anna Airy

Anna Airy, Verdure and Decay, watercolour

In a recent post I featured Anna Airy, who documented the factories in World War I.

She also wrote an instructional book called "Making a Start in Art."
Here are some excerpts:

Eye level

"You will find, by holding up your pencil or brush horizontally on a level with your eyes and extending it forward to arm's length, a mental horizontal line across your view. The boundaries of your picture having been decided by framing it with your hands, translate that mental observation into an actual light pencil line right across your paper, the eye level, and mark it E.L."

Don't touch wet watercolour
"Do not touch wet watercolour—wait. However bad it looks when wet, it will not look so bad dry and you will get over the trouble more easily."

Half-closing the eyes
"It is very helpful to half-close your eyes every now and then when working; look through the lashes; this partially shuts out for the moment masses of detail that may be worrying you. This is not done with the idea that the detail may be left out to avoid trouble, but to let you see how subservient is that intricate detail to the picture seen as a whole."

Keeping things in proportion
"Do not be led away into making a lot of little measurements, each of which is in all probability a little wrong (and error multiplies): run your eye over your subject as a whole and take note of the proportion of big things to one another, remembering that the greater is bound to contain the less, so that if you get your few big proportions roughly correct, all the smaller objects will fall into their places without much difficulty."

Should we ignore detail?
"Never say, 'Oh! I don't see detail' and 'The detail doesn't matter.'"

How to paint a background around a complicated shape in watercolour
"Take a good brushful of the background colour and go carefully round your difficult flower petals first, leaving a real wet track. It will not dry in a hurry; if you wanted it to you would have to wait a long time! Then start your background wash at the top as you have done in previous examples, and continue it down until it meets the already wet colour round the flowers. When the washes meet you will have more wet colour than you want round the flower petals; take the squeezed-out brush, as before, and very lightly remove some: the remaining wet colour will probably settle itself quite comfortably. You must be neat-handed and careful! Or you can remove the extra moisture with a little corner of blotting paper, like taking off ink blots. Or you may effect the whole process by turning the work upside down."


Assorted thoughts
• "Our business is to be the eyes and the brain for other sorts of people."
• "Key your picture from its highest light, which we will assume to be, as it so often really is, the sky.
• "Don't look at the thing you're painting, look just beside it." (Attributed to James J. Shannon)
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Book on Amazon: Making a Start in Art
Previously: Anna Airy's Industrial Art

Portraits in the Audience

At the Portrait Society Conference, everyone is a model—wittingly or not—including a member of the audience near me.

This sketch uses a limited palette of gouache: Light Red by Shinhan Pass, and then the rest by M. Graham: Yellow Ochre, Ultramarine Blue, Ivory Black, and Titanium White. (Links take you to Amazon pages).

Shopfront Perspective

I chose pencil and gray wash for drawing these storefronts in New York state. The perspective is slightly off-angle, with remote vanishing point for the facades far to the right.  

To keep all those gently sloping lines in relationship to each other, I drew a grid of preliminary guidelines, starting with the eye level (which runs through the middle of the shop windows).

The other key foundational line is the line at the top of the building. You can still see that light guideline near the top of the cornice of the Bauer building. The intermediate lines of the facade are interpolated between those two lines.


When composing a picture with a storefront or any architecture, one choice that you have to make early on is whether to paint it straight-on in one point perspective (where all the horizontals of the facade stay horizontal), or whether to introduce some convergence.
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Previously on GJ: Perspective Tip

Using a Pencil to Check Measurements

Yesterday I painted a street scene in Hudson, New York. (Link to video on Facebook)

I choose a limited palette of gouache: purple, lemon yellow, white, and two shades of raw umber. (Raw umber varies a lot by brand; the Shinhan is really more of a raw sienna). I add vermilion later on as an accent color.

The limited palette unifies the color scheme, and it's fun to try to mix a green with that blue-leaning purple and green-leaning yellow. 

In the video, I'm using a time-honored method for checking measurements. I choose a unit of length— the apparent height of the opening of green awning. 

I mark off that segment by choking up on my pencil held at arm's length. Then I transfer a comparable unit to my drawing and use that unit of measurement to check other things. It's a good way to guard against errors and to get a reasonably accurate basis for the picture.
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I'm using Shinhan Pass Design Water Color/Gouache and M. Graham Gouache in a Pentalic Aqua Journal.

Rackstraw Downes and the Rotating Viewpoint

Rackstraw Downes, "At the Confluence of Two Ditches Bordering a Field
with Four Radio Towers" (1995), 46 x 48 in. 

Rackstraw Downes (born 1939) has an interesting approach to perspective which often results in unexpected twisting of the lines in the scene, such as the way the catenary curves of the power lines above are conveyed with compound curves.

Downes points out that the early perspective theorists offered two competing ideas for how to translate the 3D world onto a 2D surface. One is the familiar straight-line perspective codified by Leon Battista Alberti in the early 1400s.

Jean Fouquet, Arrival of Emperor Charles IV...
1455-1460.

Around the same time, other artists explored a way to interpret perspective using curving lines. But curved-space perspective mostly fell out of favor for centuries, until recently.

360-degree panorama. Photo: Heiwa 4126

Curved space projections look familiar to us now, thanks to wide angle lenses and the rotating cameras that can capture a 360-degree field of view.

In many of his paintings, Downes uses a curvilinear perspective that's reminiscent of these photographic approaches. The painting below takes in more than 90 degrees. 

Albertian perspective requires holding the head in one line of sight, what Downes calls a "head-in-a-vise" system. Downes' vistas often take in a 180 degree view, which would only be possible if you turned your head from one direction to another.

Such head-turning is in some ways more natural. It's what we do when we look around in a scene. Downes wants to capture this experience "empirically," a word he uses a lot. He's not terribly interested in following a strict geometric system, but would rather interpret the scene each time as he sees it.



Sometimes the resulting paintings have idiosyncratic features. For example, in the scene above, the horizon or eye level is below the center of the image. That would normally require it to be cupped upward in a concave fashion. But instead, Downes sees the horizon as bulging upward convexly. This would only happen in a photo if you pointed a super wide angle lens downward and cropped off the bottom half of the image.

Downes also makes the line of the building at left leaning straight outward, rather than curving back into the scene at the top like a parenthesis, as a normal wide angle perspective would require. These idiosyncrasies of perspective might strike different people in different ways.

To me this one has a queasy, funhouse feeling, and also the sense that the city scene is on the surface of a small spherical planet.



Downes lays out the case for his approach to perspective in an essay called "Turning the Head in Empirical Space," which appears in the back of his book Rackstraw Downes, published in 2005 by the Princeton University Press.

Another good book is Rackstraw Downes: Onsite Painting, 1972-2008

Lasar's Angle Measurement Device

In 1891, artist Charles Lasar patented this device to help draw angles accurately. The device consists of a wood frame with a screw eye (B) attached on the inside of the frame, halfway along one of the inside edges. A plumb bob (C) hangs from that screw eye, with the free end stretched across a series of graduated angle marks radiating from point B. 

Lasar describes how to use it: "The frame is held up vertically, so as to show within its outlines the object to be drawn—in this case a house. The plumb-line is brought parallel with one corner of the house or the chimney and thus maintains the frame in a vertical position. Now look through the screw eye at the apex of the gable and bring the loose string to coincide with the left line of the roof. Holding the string against the frame, lay the frame over the drawing-paper and trace thereon the direction of this roof-line. Get the other gable line in the same way, then the ridge-line, and so on, as may be necessary, and the resulting drawing must be correct in perspective."

Previously: Charles "Shorty" Lasar on Posing a Model

See also: Practical Hints for Art Students by Charles Lasar, 1910. (Free edition on Google Books)

Thanks, Kev and Linda

Circles in Perspective

Here is some basic but valuable information about circles in perspective. 

Ellipses on the top and bottom of an object do not have the same degree. If you're looking downward at an object, they are skinnier at the top of the object, and they appear fuller as you look lower down on the object. 

This diagram comes from the Famous Artists Course. The instructors recommend constructing a transparent box around the lamp to help get the ellipses right. The eye level (or horizon) in this diagram is up at the top of the image, where the lines vanish to a dot. The square cross sections can be subdivided to find the center line, center points, and the square-in-perspective on which each ellipse can be fitted.

A circle at the height of the eye level would be seen perfectly edge-on, and would thus be a straight line.



The same principle applies to ellipses above the horizon. When I drew this round tower, I first established the eye level. It's near the bottom of the small arch-top window in the middle of the picture.

At that level the ellipse flattens to a straight line. I drew the other ellipses becoming progressively fuller as we approach the main ellipse of of the tower's roofline. Having those lightly drawn ellipses in my preliminary drawing helped me place the windows and the courses of stonework.
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Check out my Instagram page, where I'm sharing theme park sketches.

Canaletto Up Close

In honor of Canaletto's birthday today in 1697, let's take a look at one of his paintings. His method of painting is quite unusual.

Canaletto, The Bucintoro at the Molo on Ascension Day

Nowadays most oil painters would go for a general overall impression first and refine it further and further with spots of paint. 

Canaletto is rhythmic and precise, like visual music. The way he achieved this look was by painting the big background tones first. When those tones were completely dry, he would go back in with paint on a long thin brush and define the smaller forms almost like calligraphy. 

Because of the drying time, I would guess that he would have had several canvases going at the same time. 

Overlapping forms like figures and boats were painted from background to foreground. So those stairs going down to the water were painted all the way across and allowed to dry before the figures were added over them. 

As the paint has transparentized slightly over the centuries, you can see the earlier layers through the figures.

This method of painting takes some faith and some visualization, because you have to anticipate many steps ahead. The procedure would not work very well in oil on location unless you painted it in a two day session. But it would work extremely well with casein or gouache, where the drying time and opacity encourage such handling.

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Related posts:

Veduta

Plein-air architecture in two day sessions (Bonington and Canaletto)

Berkey House Portraits

Confetti

Eye Level in Complex Street Scenes

In the upcoming issue of International Artist magazine (April/May 2015, Issue #102), I'll present an article about how to establish the eye level line in a scene, and why it's important.

If you were standing in front of an ocean or a flat desert, the eye level would be the same thing as the horizon. But in many scenes, the horizon is not visible. So you can think of the eye level as the line of your level gaze, where the horizon line would be if you could remove everything in front of it.

Layout sketch for Dinosaur Boulevard, pencil on tracing paper, 5 x 10 in.

When I planned the painting "Dinosaur Boulevard" for Dinotopia, I did a lot of small layout studies like this one. The eye level is drawn right through the whole scene, and marked "EL." The eye level is important here because it establishes the height of the viewer in relation to the scene. The line intersects all the forms—human and saurian—about five and a half feet.

Dinosaur Parade Layout, pencil layout, 7 x 14 inches

Here's an early sketch for Dinosaur Parade, drawn in pencil from my imagination, before I sought out any references. The actual ground plane shifts as the figures descend the stairs, but the eye level is still essential for the construction of the perspective and the placement of the figures.
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This will be my 34th consecutive article for International Artist, the magazine which GurneyJourney readers rated #1 overall.
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The paintings in the article are all currently on view in Stamford, Connecticut through May 25.
I cover this topic in Imaginative Realism: How to Paint What Doesn't Exist
It's also covered in How to Draw by Scott Robertson
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