photo - whole telescope

Maker: Du Jardin, Pierre

Year: 1620 c.

Year Range: -

Year Notes:

Manufacturing Location: France [?]

Signature: PD

Signature Notes:

Inscriptions:

No stand present.

Collection: Coll. Willach

Accession #: RW 099 [1699] [lots] [2023]

Sources:

Project investigation. Further information can be found in Bolt & Korey, "The world's oldest telescopes," in THE ORIGINS OF THE TELESCOPE (Amsterdam, 2011), pp. 237-8.

Public Notes:

Four cardboard tubes covered in blue and pink marbled paper. When collapsed forms a cylinder enclosed by end caps. Objective of 23 mm stopped down to 19 mm. Very little information known about Dujardin (1594-1645). He was known for sundials. Negative eyepiece. Both lenses held in place with spring. Paper gasket to hold in place. End rings (ferrules) made of wood. Magnification 14x.

Length (open):

Length (closed):

F-ratio:

Exit pupil:

Object status:

Objective type: singlet

Optical style

Physical style

Functional style

Materials: paper, pasteboard, glass, wood, leather, gold tooling

Drawtube data:

Drawtube notes:

Objective Data

	CA curvature (diopters):	CB curvature (diopters):	PD lens power (diopters):	fD focal length (mm):	t thickness (mm):	free aperture (mm):	full aperture (mm):	nD refractive index:	ν Abbe No.:
Lens 1				670.00		23.00	19.00

Eyepieces

Notes:

Eyepiece 1

	fD focal length (mm):	free aperture (mm):	full aperture (mm):	s spacing (mm):	CA curvature (diopters):	CB curvature (diopters):	M magnification:	FOV field of view (degrees):	Thickness:
Lens 1	48.00		19.00