Telescopes

1.23m Telescope

Schmidt Telescope

* undersized secondary


corrector		prime-system		RC-system	IR-system
corrector		2 lens	3 lens	RC-system	IR-system
aperture	mm	3 500
focal length	mm	12 195	13 761	35 000	157 500
central obscuration	mm ø	820		1367	281.66
eff. coll. area	m²	9.093		8.153	8.969*
f/ratio		1/3.48	1/3.93	1/10.0	1/45
FOV	mm	100	243	300	109
	arcmin	28.19	60.71	29.47	2.38
scale	"/mm	16.9	15.0	5.89	1.31
radius of field curvature	mm	infinite		-3786
hourangle range	h	-7 to +7

Image of the 3.5m-telescope (399 kByte)

Cut through 3.5m-building (17 kByte)

		RC focus		Coudé focus
		with	without
		Corrector
aperture	mm	2200
focal length	mm	17 037	17 611	88 000
central obscuration	mm ø	1046	887	656
eff. coll. area	m²	2.942	3.183	3.463
f/ratio		1/7.744	1/8.005	1/40
back focal distance	mm	1216	1216.5	14 100
focal range	mm	240	240	5 000
FOV	arcmin	67	33	5
	mm	332	170	128
scale	"/mm	12.1	11.7	2.34
radius of field curvature	mm	infinite	-2228
hourangle range	h min	-16:40 to +16:40

Image of 2.2m-telescope (401 kByte)

Cut through 2.2m-building (20 kByte)

		with	without
		Corrector
Aperture	mm	1230
Focal length	mm	9807.6	9857.1
Central obscuration	mm ø	582
Eff. coll. area	m²	0.922
f/ratio		1/8
Back focal distance	mm	852.1	849.9
Focal range	mm	± 200
FOV	arcmin	90.2	90.0
	mm	257.2	258.1
Aberration free	arcmin		15
	mm		43.0
Scale	"/mm	20.9
Hourangle range	h min	-15:06 to +14:50

Corrector Details

&nbsp	Lens 1	Lens 2
Diameter	290 mm	280 mm
Aperture	276 mm	258 mm
Shape	convex concave, spherical	biconcave, spherical
Center thickness	25.1 mm	24.4 mm
Surface	antireflective coating on both sides, reflection minimum at 550 nm	antireflective coating on both sides, reflection minimum at 550 nm
Material	Quartz glass	Quartz glass

Image of 1.23m-telescope (354 kByte)

aperture	mm	800
focal length	mm	2400
f/ratio		1/3
FOV	°	8
	mm	335
plate format	inch	8 x 10
scale	"/mm	86.2

Two objective prisms with 590 and 1390 Å/mm at 430 nm

Image of Schmidt-telescope (154 kByte)