Celestron 91078 Manual De Instrucciones página 4

3. Point the astrograph at a bright star and focus the camera. Center the star in the camera's
field of view. Use Polaris, if possible, as it won't move much over time.
4. Defocus the star by about 1 turn of the focus knob.
5. Inspect the defocused star pattern. When collimated, the pattern should look like a
concentric doughnut. If the pattern is concentric, no adjustment is necessary. If the
"donut hole" is not centered within the pattern, then some adjustment is needed.
6. There are three pairs of collimation screws. Each pair works together as a push-pull tilt
adjustment. Adjust the collimation by loosening and tightening one of the pairs of
Specifications
Optical Design
Aperture
Focal Length
Focal Ratio
Central Obstruction
Optical Coatings
Optical Window
Focuser
Cooling Fan
Tube Dimensions
Tube Weight
Back focus (from top of lens group housing)
Back focus (with M48 camera adapter)
Spot size
Wavelength Range
Off-axis Illumination
Image Circle
Usable Field
FCC NOTE: This equipment has been tested and found to comply with the limits
for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is
no guarantee that interference will not occur in a particular ninstallation. If this
equipment does cause harmful interference to radio or television reception, which
can be determined by turning the equipment off and on, the user is encouraged
to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
This product is designed and intended for use by those 14 years of age and older.
4 | E N G L I S H
collimation screws. Always loosen one of the screws first, then tighten the other one.
Adjust one pair of screws at a time.
2 mm
Hex key
3 mm
Hex key
7. If the star pattern is thin on one side, adjust the collimation screws so that the star moves
towards the thin side, then adjust the position of the astrograph to re-center the star. Repeat
this until the defocused star image is concentric.
Rowe-Ackermann Schmidt
355.6 mm
790 mm
f/2.2
158 mm (44% of aperture diameter)
Enhanced aluminum, Starbright XLT multi-coatings
104 mm Ø, removeable
Ultra-Stable Focus System (USFS), mimimizes focus shift
12V DC, MagLev
42.5 inches length, 16 inches diameter
75 lb
77.5 mm
55 mm
< 6.3 μm RMS across FOV
400 – 900 nm
83% at 30 mm off-axis
60.1 mm Ø , 4.3 degrees
70 mm Ø, 5.1°, only minimal performance loss at edge of FOV
WARRANTY
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