How 17th century scientists made pinholes?

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17th century scientists like Fresnel and Fraunhofer, although primarily active in the 19th century, contributed to optical equipment development, including gratings and pinholes. A simple method to create a pinhole involves using aluminum foil and a pin, while gratings can be made by coating glass with soot and drawing parallel lines with a razor. David Rittenhouse created one of the earliest diffraction gratings in 1785 using human hairs, a technique later refined by Fraunhofer. The advent of photography around 1830 likely influenced the methods for creating optical devices. The discussion highlights the evolution of optical techniques and their historical context.
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I am highly curious about how did 17th century scientists like Fresnel, Fraunhofer, etc. made optical equipment such as gratings, pinholes, etc.?
 
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Make your own pinhole:
Take a piece of aluminum foil. Poke a pin through it. You have a pinhole.

Make a grating:
Coat a piece of glass with soot. Take a straight edge and with a thin razor, draw consecutive parrallel lines on the soot.

It might be how those guys did it but do not quote me on it.
 
Fresnel and Fraunhofer were both early 19th century physicists, not 17th.

"In 1785 Rittenhouse made perhaps the first diffraction grating using 50 hairs between two finely threaded screws, with an approximate spacing of about 100 lines per inch. This was roughly the same technique that Joseph von Fraunhofer used in 1821 for his wire diffraction grating." -- http://en.wikipedia.org/wiki/David_Rittenhouse

Photography dates back to ca. 1830, which is not much later than Fresnel and Fraunhofer. I don't know, but I would guess that once photography came along, they started using optical reduction to make gratings.

Interesting stuff here about natural diffraction gratings: http://rsif.royalsocietypublishing.org/content/2/2/1.full
 
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