Vixen VMC260L User manual

VIXEN ORIGINAL MAKSUTOV CASSEGRAIN
VMC
VMC260L for SXD

This manual applies to the VMC260L telescope for the SXD equatorial mount. You may occasionally finde descriptions in the text not
relevant to your particular model. Read the instructions for your mount along with this manual if you purchased the telescope as a
complete package.
① With the Allen wrench,
loosen each of the rear three
setcrews on the bracket ring
that holds the finder scope.
Loosen the front adjustment
screws on the bracket ring to
allow passage of the finder
scope.
② Slide the finder scope into the bra-
cket ring from its eyepiece end and
tighten the setscrews on the bracket
ring lightly with the Allen wrench.
③ Tighten the three adjust-
ment screws to hold the
finder scope steady
④Loosen the chrome setscrew
of the bracket shoe on the
telescope. Slide the finder scope
onto the bracket shoe and
thighten the chrome setscrew
① Loosen the dovetail tube plate
lock screw and the safety screw
before you attach the optical tube.
② Slide the dovetail slide rail on the
bottom of the optical tube onto
the mounting platform.
Tighten the lock screw on the
slide rail until snug. Tighten the
safety screw.
󰄥Do not leave the optical tube uncapped in the daytime. Sunlight passing through the telescope or finder scope may cause a
fire.
󰄥Do not use the product while moving or walking, injuries could result from a collision with objects or from stumbling or falling.
󰄥Keep small caps, plastic bags, or plastic packing materials away from children. These may cause a danger of swallowing or
suffocation.
󰄥Do not use the product in a wet environment and do not handle with wet hands.
󰄥CAUTION
• Attaching the Finder Scope
• Attaching the Optical Tube
Finder Bracket
7x50 Finder
Allen Wrench
Setscrew Adjustment Screw
Optical Tube
Carry Handle
Finder Shoe
Chrome Setscrew
7X50 Finder Scope
Adjustment Screw
Finder Bracket
Dovetail Slide Rail
Safety Screw
Lock Screw
Refer to your mount instructions along with this manual.
Thank you very much for your purchase of a Vixen astronomical telescope.
Never look directly at the sun with the telescope or its finder scope or
guide scope. Permanent and irreversible eye damage may result.
WARNING
PREFACE
SETTING UP
2

The telescope requires eyepieces to view images. An eyepiece is not included
with the VMC260L.
①Choose a conspicuos target in the distance
and place the target in the center of the field
of view of the telescope.
In the illustration, a distant tower is brought
into the center of the field of view of the
telescope.
②As you look through the finder scope, you
should find the same target somewhere
within the finder‘s field of view. The finder
scope has a crosshair.
③Align the optical axis (field of view) of the
finder scope with the optical axis (field of
view) of the telescope. Adjust the finder
scope by loosening or tightening two of the
three adjustment screw at a time, in turn,
until the target is in the same position, in
the center of the crosshair.
• Adjusting the Finder Scope
VMC 260L for SXD
Focus Mount
SX60→50.8AD
Diagonal
31.7mm Eyepiece
Flip Mirror Diagonal
#2956
Extension Tube VC
EA60mm to 50.8mm
#3725
CCD Adapter F
CCD Video Camera
C-Mount Tele-
Extender 2.4X
T-C Ring
C-Mount Reducer 0.6X
SLR Camera
T-Ring
Detaching the inner ring
of T-Ring
Wide Photo Adapter 60mm
Camera Adapter 43 DX
Focal Reducer
Eyepiece Adapter
42mm to 31.7mm
push-fit
NLV Eyepiece
DG-NLV DX Digital Camera Adapter
Digital Camera
Camera Adapter 43 DX
NLV Eyepiece
Extension Tube
VC
64mm DC
Ring
55mm DC
Ring
SX60-50.8AD
VMC260L
Focus Mount
(Eyepiece Holder) (Connecting Tube)
(Direct Focus
Photo Ring)
Eyepiece Projection Camera Adapter
Field of view of the 7X50 finder scope
Field of view of
the finder scope
Finder Bracket
Target
In the
center
of the
Telescope‘s
eyepiece.
A: Screwing
the bolt
B: Fastening the finder scope by
turning the nut
(Visual Configuration )
(Photographic Configuration )
Nut
ACCESSORY CHART
ALIGNING THE
FINDER SCOPE
3

How to Re-collimate the VMC260L Optical Tube
1. Re-collimation of the optical axis will go much faster if you have an assistant.
2. The star image will shift considerably even if the collimation screws are adjusted only a small amount.
3. If one of the three collimation screws comes to the end in either direction, turn the other two collimation screws on the opposite
side to the reverses so that you can continue the re-collimation.
4. Optical collimation is very delicat and you should avoid turning the collimation screws excessively.
Specifications Handling and Storage
① There are threee Allen
screws for collimation
which are placed near
the center the four-
vane spider on the
front of the optical
tube.
② Attach an eyepiece with
medium power (60X to
80X) onto the eyepiece holder and get a relatively bright
star such as the Polar star into the telescope´s field of view.
Turn the focus knob to defocus the star image fully until it
is enlarged and blurred as much as one third of the viewing
field. The silhouette of the secondary mirror is seen near the
center of the
blurred star
image at this
time.
RE-COLLIMATION
③ If the optical axis is aligned correctly, both the blurred star
image and silhouette of the secondary mirror can be seen at
the center of the telescope‘s field of view. If it is not aligned
concentrically, move those images to the center of the field
of view. With an Allen wrench, adjust the collimation screw
nearest or furthest from the direction of those images.
The VMC260L telescopes are collimated properly at Vixen‘s factory before shipment. The telescopes hold the
collimation unless they are handled roughly. You can re-collimate your telescope using the following procedure if
necessary.
④ Turn the collimation screw clockwise or counterclockwise
gradually until the blurred star image and silhouette of the
secondary mirror are aligned concentrically in the center
of the telescope‘s field of view.
⑤Use an eyepiece with high magnification and repeat the
above procedures so that you can make more precise
re-collimation of the optical axis.
⑥When re-collimation of the telescope is done properly,
you perform a star test
with a medium to high
power eyepiece selecting a
star of the second or third
magnitude.
Right after you focus on the
star precisely, defocus the
star image slightly to look at
a diffraction pattern of the
star.
if the concentric diffraction
rings can be seen, the
optical axis have been
re-collimated properly.
Spider
Collimation
Allen Screws
Secondary
Mirror Holder
Misaligned largely
Out of collimation slightly
Collimated properly
Silhouette Silhouette
- Do not leave the product inside a car in bright sunshine or in other hot
places. Keep away strong heat at sources away from the product.
- When cleaning, do not use solvents such as paint thinner or similar
products.
- Avoid touching any lens or mirror surfaces directly with your hands.
In case a lens or mirror becomes dirty with fingerprints or general
smears, gently wipe it using a commercially available lens ceaner and
a lens cleaning paper or cloth, or consult you local Vixen dealer.
- Blow off dust on lenses using a commercially available blower brush.
- For storage, keep the product in a dry place and do not expose to
direct sunlight.
Model VMC260L Optical Tube Assembly
Optical Design Precision Spherical Mirror & Meniscus Lens System
Effective Aperture 260mm
Focal Length 3000mm
Focal Ratio 1 : 11.5
Light Gathering Power 1380X
Resolving Power 0.45 arc seconds
Limiting Magnitude 13.8
Threads 60mm, 42mm for T-Ring
Visual Back 50.8mm (2.0“), 31.7mm (1.25“)
Optical Tube Length 650mm
Outer Diameter 304mm
Weight 10.9 Kgs (24 lbs)
7X50 Finder Scope
(6.8 degrees field of view) Supplied
Flip Mirror Diagonal Supplied
Mounting System Dovetail Slide Rail and Mounting Platform
Carry Handle Supplied