Specifications

Section 5 - Hints and Tips
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• Images will always look better when displayed on a video monitor, however, an active
matrix LCD display is pretty close except in brightness.
• You may wish to change your display and hard drive sleep cycles (battery conservation) to
longer "keep awake" times so as not to interfere with image acquisition (long Track and
Accumulate).
• LED flashlights help to see the keyboard when the display is dimmed red.
5.4. Telescope Tips
• Always verify best collimation prior to installing the CCD camera.
• Always secure the camera head cable to the optical tube assembly. Never let the cable
dangle free from the focuser/ocular holder.
• Off-axis guiding is worth it, even on a bunch of 3 minute co-adds of a deep sky object.
• Don't guess on focus. If you're not sure, it is time to refocus.
• Take time to frame your object. Rotate the camera 90 degrees to take advantage of the CCD
chip's 3:4 aspect ratio and don't forget to refocus again.
• Focal reduce as much as possible for deep sky objects. Exposure times are then shorter and
signal to noise gets better. 2-3 arc-seconds per pixel (30" focal length) is plenty of resolution
for deep sky objects, especially nebulae. Good tracking is still critical down to 12" focal
lengths in hi-res mode. Always polar align to minimize Dec drift.
• Focusing micrometers really help, especially on SCTs where you want to always enter the
best focus position on a counterclockwise knob rotation. This advances the primary mirror
forward against gravity and preloads bearings, screw threads and any mirror/baffle
rocking. A light knuckle rap prior to exposure or guiding is advisable to settle moving
components. It is always possible to ascertain exact focus only after you have passed a peak
intensity and then come back to the peak's setting. You may not see the exact high value,
but will see the trend at best focus position. Again, don't guess at focus.
• Focusing on planets is difficult since seeing can uniquely blur each frame. If a planet's moon
is present, use the slow motion hand control to move over to it. Readjust exposure time
accordingly and refocus on it, then bring the planet back into view and capture it.
• If track problems exist, first check balance in declination and then RA since they interact.
Verify the 1 1/4" camera head coupler doesn't rock in the telescope bushing and that it is
flush at it's coupler flange with bushing. Check drive clutches or clamps. Check drive rate
setting. With guiding ocular visually check PEC setting or reprogram. Trails seen on only
the brightest stars along the short axis of the CCD is blooming, not tracking.
• Real dark skies are not necessary for beautiful CCD images of deep sky objects. CCDs are
far superior to film with or without filters in this respect. Tricolor CCD will benefit from
dark skies, but still works great compared to color film.
• Simple 2 element refractors can show bloated stars due to chromatic aberration since CCDs
have a wide spectral response and a very wide dynamic range of signal. Filters can help or
quality multi-element color corrected refractors.
• Always keep an eye on ambient temperature changes. A 3 degree Fahrenheit change can
affect SCT focus enough to merit refocusing. Temperature drop = clockwise movement of
SCT focus knob (yes, the way you didn't want to move it).
• Closely re-align your finder as needed to the CCD image on the screen to speed up object
acquisition. Don't use a 90 degree diagonal to visually acquire objects and expect them to be