Baader Planetarium MPE DADOS User manual

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November 2021 – English Revision v1.6
The collaborators on the DADOS spectrograph project are:
•Max-Planck Institut für Extraterrestrische Physik
www.mpe.mpg.de
•CAOS
www.eso.org/projects/caos/
•Baader Planetarium GmbH
Zur Sternwarte
D - 82291 Mammendorf
Tel.: [phone] - 80 89-0
Fax: [phone]
www.baader-planetarium.de

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DADOS Spectrograph
User’s Guide
Thank you for purchasing this Baader Planetarium product.
To get the most out of your DADOS Spectrograph, please
read this instruction manual thoroughly before starting to work
with the spectrograph. Keep this User’s Guide available for
future reference and visit the Baader Planetarium website:
http://www.baader-planetarium.de for up-to-date information
about the product.

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Unpacking
As you unpack the spectrograph, check the list below and
make sure that all items shown above are included. If anything
is missing contact your original retailer.
Standard accessories:
• DADOS spectrograph • Allen Wrench 1.5 mm
• Eyepiece 20mm • Allen Wrench 1.3 mm
• Eyepiece 10mm • 1 ¼" Stop ring 1905131
• Slit Viewer Assy. (Guiding lens with M28.8-thread)
• T2 Quick Changer #2456313 (mounted at the Dados)
• T2 Quick Change Ring #2456320 mounted at the eyepiece
barrel with Focusing eyepiece holder (#2458125)
• Gloves for changing the grating • Storage Case & Manual

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Part description
1. 2” Nosepiece
2. Slit illuminator
3. 1 ¼” Slit viewer port
4. Slit-viewer port locking screws
5. Micrometer
6. Rotation stage counter spring
(pre-adjusted, do not touch)
7. Focuser
8. Focuser locking screw
9. Grating angle locking screw
For a full list of accessories see Appendix D

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Table of Contents
1. INTRODUCTION 8
2. QUICK SETUP 10
2.1 Attaching an eyepiece to the focuser 10
2.2 Focusing the spectrum 11
2.3 Changing the spectral range 13
2.4 Observing some common light sources 14
3. CONFIGURING DADOS FOR ASTRONOMICAL
OBSERVATION 18
3.1 Coupling a detector to DADOS 19
3.1.1 Astronomical CCD camera 19
3.1.2 SLR or D-SLR body 22
3.2 Fine focusing of the camera objective 24
3.3 Selecting wavelength range 25
3.4 Using the slit-viewer 26
3.4.1 Attaching an eyepiece to the slit-viewer 26
3.4.2 Attaching a webcam to the slit-viewer 28
3.4.3 Zooming the slit view in and out 31
3.5 Coupling the spectrograph to the telescope 33
3.6 Operating the spectrograph at the telescope 34
APPENDIX A: MAINTENANCE 36
A.1 Battery replacement 36
A.2 Grating replacement 37

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APPENDIX B: CARE OF THE OPTICAL
COMPONENTS 43
APPENDIX C: SPECIFICATIONS 44
APPENDIX D: OPTIONAL ACCESSORIES 46
APPENDIX E: BIBLIOGRAPHY 47

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1. Introduction
The DADOS spectrograph is an instrument that displays the
spectra from different light sources. The name DADOS means
“dice” in Spanish. It was designed to be used as either a
spectroscope or as spectrograph, mainly for astronomical and
instructional purposes. The device is very easy to use, robust,
and versatile.
Please read this entire manual carefully to achieve the
maximum use from this device.
The DADOS’ main features are:
•Optimized for telescopes up to 14” aperture at f/10.
•Choice of 3 slits: 25, 35 and 50 μm.
•A red LED provides background illumination of the
slits for easier focusing of a self-guiding camera.
•Default grating of 200 l/mm for low resolution,
optional 900 l/mm grating for higher resolution.
•Micrometer for fine positioning of the central
wavelength.
•The objective camera port has a built-in wide
focusing range and uses the standard T2 adapter
thread (M42 x 0.75).
•Accepts most CCD and DSLR cameras (with
optional adapters). The camera interface is a T2
adapter with a standard M42 x 0.75 thread.
•The wide 55mm focusing range is suitable for
attaching a DSLR-camera.

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W
WA AR RN NI IN NG G
Never aim DADOS straight to the Sun!
Irreversible eye damage will occur!

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2. Quick setup
2.1 Attaching an eyepiece to the focuser
Remove the T2 dust cap by
rotating it counterclockwise.
Mount the Baader T2 quick
changing system (#2456313
+ #2456320).
Lock the Baader T2 quick
changing system and mount
the focusing Baader eyepiece
holder (#2458125).

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Insert the DADOS 20mm
eyepiece (or the DADOS
10mm eyepiece for higher
magnification) into the
focusing eyepiece holder.
Lock the eyepiece with any of
the three locking screws.
2.2 Focusing the spectrum
Point the 2” nosepiece
(#1 on the page 5 diagram) to
a fluorescent light source or a
neon lamp.
Do not point
directly to the Sun
Rotate the focuser (#7) in
order to focus the spectrum.

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Lock the focus with the
locking screw once sharp
focus is achieved.
Rotate the focusing eyepiece
holder for fine focus
adjustments.

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2.3 Changing the spectral range
Slightly loosen the grating
angle locking screw (#9).
Center the spectral lines of
your choice by adjusting the
micrometer.
Tighten the grating angle
locking screw (#9) to secure
the selected setting.

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2.4 Observing some common light sources
DADOS lets you observe and analyze a large variety of light
sources. Specifically, you can quickly set up the instrument to
observe:
•Neon lamps
(some pilot lights in washing machines, multi-outlet
power strips, etc.)
•Fluorescent lamps
•Continuous spectral sources
(like tungsten or halogen lights)
•Bright daylight
Aim at the clear blue sky well away from the sun
Never point directly
towards the Sun.

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Examples of spectra taken with DADOS and a 200 lines/mm
grating:
HeAr calibration lamp
Neon
Continuous 1st and 2nd order
Solar spectrum
Note:
Spectra obtained with Canon 10D EOS Camera at different
grating angles.
The calibration Lamp is only visible in the dark. Shield it
from daylight or connect it to DADOS.

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Examples of spectra taken with DADOS and a 900 lines/mm
grating:
HeAr calibration lamp
Neon
Fluorescent
Continuous
Solar spectrum
Note:
Spectra obtained with Canon 10D EOS Camera at different
grating angles.
The Calibration Lamp is only visible in the dark. Shield it
from daylight or connect it to DADOS.

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3. Configuring DADOS for
astronomical observation
The spectrograph should be set up correctly to ensure proper
function.

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3.1 Coupling a detector to DADOS
3.1.1 Astronomical CCD camera
The DADOS optical design is optimized to cover the field of
CCD-chips with a dimension of 13,8x9,2mm and a pixel size
of 9µm.
Detectors having larger chip size than 13.8 x 9.2 mm may be
used; however, the optical image quality, and therefor the
resolution, will slightly decrease at the edges.
Prepare the detector to be
used in the observation,
preferably:
SBIG ST-402ME, STF-8300,
FLi ML 1603
Use the Baader T2 quick
changer system as the ideal
device for coupling and
rotating the camera without
loss of focus.

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Mount the T2 change ring
onto the SBIG detector.
Mount the quick changer onto
the T2 male thread of the
DADOS collimator focuser
(#7).
Join the detector and the
change ring combo.
Rotate the camera into the
desired orientation.