Sunday, November 10, 2013

Kashkul

The initial drawing for this painting is in the previous post. Here I have started to develop the fruit (physalis,  or Cape gooseberries) in the begging bowl - or "kashkul" as I have discovered.
Technical note:The ellipse that forms the mouth of the brass cup was carefully calculated and drawn using a loop of string and a template.
I knew what the long axis and the short axis of the ellipse needed to be by scaling a photograph of the set-up to the required size and measuring it. I then applied a formula to those measurements (it in not difficult, but you can go to this website and use the online calculator: http://www.cleavebooks.co.uk/scol/callipse.htm)


First of all, to draw an ellipse with a loop of string, you need two foci (F21 and F2 above). Place pins in these foci and measure the string so that the loop is twice the length from F2 to X  - this length will equal the sides of the triangle from F1 to Y to F2 and back to F1. (The short radius "b" is the distance from the centre C to Y; the long radius "a" is the distance from C to X, and is equal to the distance from Y to F1 - or Y to F2!)
Loop the string over the pins in the foci, pop a pencil in and stretch the loop fully as you draw, and you will get a perfect ellipse.
For the pastel, I drew the ellipse on a spare piece of card, carefully cut it out, and used the card as a template to draw the ellipse on the support - it's safer and more accurate than drawing directly on the support.

Initial block-in of cup and fruit was done with a selection of pastel pencils, both CarbOthello and Derwent, and a few Rembrandt sticks.

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