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Latest revision as of 01:04, 14 January 2020

Before the CCD

Originally published August 2, 2010 LPOD-Aug2-10.jpg
still life by Randall Rosenfeld, Toronto, Canada

Some early drawings of the Moon were made with crayons. Here are modern versions of tools for such drawings according to John Russell (1772) (from the left):

tortillons, or stumps - two of these are shown, rolled from parchment (bovine source) and secured with thread. The tortillon is used either to disperse a pigment on the page, or blend multiple pigments together once laid down.

porte-crayons - three of these are shown, made from plated copper-alloy and hard wood. The porte-crayon is a holder for pigments. The first carries a dark-sanguine crayon (non-oil-based pastel), the middle one holds a black crayon, and the last a white crayon.

quill knife - hand-made from carbon steel and hardwood. This was used for shaping and sharpening the crayons, correcting mistakes in the drawing, or for "levelling" irregularities on the page (the levelling is the only technique I haven't tried!).

pin - made from steel. Used to touch-up details by precisely removing small bits of crayon from the image.

blue-grey tinted paper - made from 100 percent cotton. This has a copy of the 1675 drawing of the Mare Orientale Complex copied from Patigny's 1675 drawing, made with the instruments shown in this still life.

rag - linen. Used for blending pigments, or for preliminary cleaning of tools and fingers!

porte-crayon - another form of porte crayon, made from reed cane (arundo donax), from Provence. It holds a light-sanguine crayon.

bread(!) - for erasing pigment. It would be employed much as an eraser is used today by a modern artist. If the selenographer was really hungry, and had good teeth...

note-book - limp-vellum binding, with pages of hand-made paper. This could be used as a log-book, or for general sketching. It's a speculative reconstruction of a small 17th-century observer's book.

Randall Rosenfeld

Technical Details
Photo from "Paris 1675: The Earliest Known Drawing of the Mare Orientale Complex" by William Sheehan, Françoise Launay and Randall Rosenfeld (in press in the Journal of the Royal Astronomical Society of Canada (English) and in l'Astronomie (SAF) (French)).

Related Links
John Russell's Face of the Moon pastel drawing


Yesterday's LPOD: How Thick Are the Alps?

Tomorrow's LPOD: Undesired, but Pretty Atmospheric Optics


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