Officina Stellare UltraCRC User manual

RC, UltraCRC, RiDK, RiLa, RiFast, RH "Veloce"
Telescopes – All models
USER MANUAL
Rev 2.0 – March. 2016 – download the latest version of this manual from www.officinastellare.com

EVEN EFORE YOU TOUCH YOUR TELESCOPE, PLEASE
READ CAREFULLY
General notes, in this page.
CHAPTER 2 – "WHAT IS IN THE OX" and
CHAPTER 3 – "HOW TO HANDLE THE
TELESCOPE"
If you handle the telescope in a wrong way, you could damage it, and such
damage is NOT covered by the warranty.
General notes about all telescopes:
Never use your telescope to look at the Sun, or even
near the Sun. Severe eye damage or even permanent
blindness may result.
Always cover your telescope in daytime or keep the dome
closed).
Never leave the uncovered telescope unattended in daytime.
Do not use Officina Stellare telescopes even to project the image
of the Sun. Pointing the Sun may produce serious damage to the
telescope. Secondary mirror, secondary mirror support or internal
electronic parts may be damaged or even set on fire!) simply by
the STRONG heat produced by the primary mirror when pointed
to the Sun.
NEVER use Herschel prisms or eyepiece filter. NEVER!!! Any
Officina Stellare telescope is far too big for such devices.
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If you want to observe the Sun, use a professional filter, placed
IN FRONT of the telescope. A 15 cm 6”) off-center Astrosolar
filter is a good and cheap solution.
If you search planets or bright stars in daytime, pay great
attention before to put your eye to the eyepiece, if the telescope
points near the Sun.
In daytime don't look into the telescope while it slews to target.
Truss structure telescopes may be "dangerous" during daytime
because the open structure allows the light to enter also laterally.
Always use the provided black elastic cover.
Officina Stellare is not responsible for any
damage related to improper use of the telescope.
INDEX
Chapter 1 – Introduction……………………..…………….. Page 4
Chapter 2 – What is in the box…………………………….. Page 7
Chapter 3 – How to handle your telescope……………… Page 8
Chapter 4 – Electronic controls…………..………………. Page 9
Chapter 5 – Collimation…………..………………………... Page 15
Chapter 6 – Collimation from scratch …………. Page 19
Chapter 7 – The RH "Veloce"………………………………. Page 33
Chapter 8 – Care and cleaning of your telescope……… Page 37
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CHAPTER 1: INTRODUCTION
Congratulations for your new telescope! Any detail of your Officina Stellare telescope, from the
primary mirror to the smallest screw, has been designed, machined and assembled to achieve the
best possible results, under any condition, both for astronomical or non-astronomical uses.
We used the best materials, the best CNC machines, and decades of experience to deliver simply
a real state-of-the-art instrument, to satisfy both professionals and the most demanding amateur
astronomers. From the optical, mechanical and electronic point of view. Each Officina Stellare
telescope, and any piece of optics mirror or lens) is 100% designed and figured in Italy*, in our
optical shop in Occhiobello near Ferrara) and in our assembly plant in Sarcedo near Vicenza).
We appreciate your feedback. Should you have any comment about your Officina Stellare
instrument, please let us know. Send your suggestions or criticisms also appreciations are
welcome, of course) to [e-mail]. We are proud to build great telescopes,
because we love astronomy. For our efforts toward perfection, only the sky is the limit.
HOW DOES IT WORK?
The figure above represents UltraCRC, RiDK, RiLa and RiFast telescopes. They all look very
similar, but:
UltraCRC telescopes are modified Ritchey–Chrétien, with a 2-lens corrector group near the
focal plane but the secondary mirror is hyperbolic, like in "traditional" RCs).
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RiDK telescopes are optimized Dall-Kirkham, with a 2-lens corrector and a spherical
secondary mirror.
RiLa and RiFast telescopes, are based on different "tuning" of the Harmer-Wynne scheme.
Like in the RiDK the secondary mirror is not hyperbolic, and this allows a bit "relaxed"
tolerance on collimation. The lens corrector group has 3 elements.
Anyway, in all such telescopes the light coming from the sky blue arrows) is focused by the
primary, concave mirror 1 & red arrows) on to a divergent secondary mirror 2). The secondary
mirror reflects again the light through a hole in the primary mirror, where a 2 or 3 lens corrector is
located green arrows and 3). The image forms at the focal plane 4) where a detector or an
eyepiece) is placed. The unique shape of mirrors and lenses, and a sophisticated system of light
baffles provide a focal plane that is reflections-free, well illuminated, wide and flat. All telescopes
provide, at the focal plane, a star spot size that is much smaller than almost any CCD/CMOS pixel.
Obviously the shape of mirror/lenses and their spacing is different in each model, to achieve the
best optical performance for a given aperture and focal ratio.
RC and RH "Veloce" telescopes are a bit different. In the RC series, a "pure" Ritchey–Chrétien
design, there is no lens group before the focal
plane and the secondary mirror is hyperbolic
figure at left). This is in theory the "best" and
simplest solution for deep sky imaging many
professional giant telescopes, including the
Hubble Space Telescope, are Ritchey–
Chrétien) but can't be done with low i.e. "fast")
f/ ratios. The size of the aberration-free focal
plane is smaller than in other schemes, and
collimation is really critical.
The RH "Veloce", on the other hand, is the
most complex optical scheme used by Officina
Stellare, but it is simply the best solution for
wide field photography, and it is the only really
new scheme for telescopes to enter production in decades! You see it in the figure below. In RH
telescopes, there is a meniscus front lens that is weakly convergent, and the primary mirror is a
"Mangin" mirror from the name of its French inventor). A Mangin mirror is a mirror that is coated
on the back surface, not on the front. The light passes through the glass, is reflected by the
coating and then passes again through the glass. For this reason, a Mangin mirror is called a
refractive-reflective optical element, and opens exciting possibilities to optical engineers. This
complex design includes also a corrector group
before the focal plane, achieving performances
impossible otherwise, with extraordinary "fast"
photographic performances over wide focal
planes. We called our RH telescopes "Veloce"
because this word, in Italian, means fast. A
curiosity about RH telescopes: since the
meniscus frontal lens) is convergent, the
Mangin mirror is smaller than the "nominal"
diameter of the scope, while the meniscus itself
is bigger than the nominal diameter, to ensure
a good illumination over the wide field of view
of such scopes. For example, the 200 mm
model has a 220 mm meniscus and a 190 mm
primary mirror. The secondary mirror is a
separated piece of glass, or it is made coating
the middle of the meniscus, depending on
model.
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