Posts Made By: Jeff Chappell

This will do it:

http://skyandtelescope.com/observing/skychart/#

You have to go into the Advanced Options to turn on the DSOs. There is an option to create a printable version as well.

Jeff

While visual viewing seldom if ever portrays the detail of astrophotos, the question was which do you prefer to view live, not which can you see more of.

My answer is "all of them". Otherwise, I'd just sell my scopes and spend time looking at photos in books or on the web.

Jeff

Bruce,

The act of polar alignment insures that the RA axis of the mount is aimed at the north pole, since that is the point in the sky that everything else rotates around. Once that is done, as long as you don't move the tripod, the mount is still polar aligned regardless of where the scope is pointing. Polar alignment refers to the mount, not the optical tube.

Now you can disengage the clutches and move the tube manually or use the controller and let the motors move it to point anywhere you want. As long as the RA clutch is reengaged and the motor is running, whatever is in the eyepiece should remain in the eyepiece as it progresses overhead from east to west. RA motion is all that's required to track. Declination motors are only useful (on an EQ mount, alt-az is another story) to slew the scope to different objects, since the declination of an object doesn't change as it moves overhead, only the RA changes.

I think you are confusing a motorized tracking scope (like your Skyview Pro EQ) with a computerized goto scope (like a Celestron Nexstar, Meade LX or ETX, etc.) which does need alignment to know exactly what point in the sky, RA and dec, that it is pointing to. Tracking doesn't care where it's pointing. You point it at whatever you want to look at and all it needs to know is how fast to move from east to west to keep up with the earth's rotation.

Now for the short answer:

1) polar align as you have done

2) point the scope at whatever you want to look at

3) engage the RA clutch

4) turn the motor on and leave it on

5) enjoy the view!

If everything is working, the view through the eyepiece should stay the same. If objects are drifting across the view, either you're not truly polar aligned, or the motor isn't running, or the clutch is not engaged. Some slight drift over longer periods of time (minutes vs seconds) could be attributed to the motor running slightly fast or slow, but this can be adjusted.

Jeff

These scopes, available under different brand names (DSH, StarHunter, original Orion XTs, etc.) are all made by Guan Sheng in Taiwan, and have been notorious for too tight secondary holders. The foam Jon mentions is one possible cause, but in my case (and many others) the plastic secondary holder is just too tight.

It's an easy fix. Wear latex gloves to avoid getting fingerprints on the mirror. Remove the mirror, by prying it out if you have to. Heating the holder with a blow dryer may help it loosen up. Then sand out the inside of the holder with some 200 grit sandpaper until the mirror slips in and out without much force. Examine the inside ring of the holder closely and you can see where the mirror is still scraping against it. Concentrate your sanding in that area.

Once it slips in and out easily, reattach the clip so that it just barely contacts the surface of the mirror. The mirror can't slip out of the holder past the clip, and the (slight) force of the foam on the back of the mirror will hold it steady.

This eliminated any astigmatism from my XT10. It's also advisable to loosen the clips retaining the primary mirror, as they are overtightened to withstand shipping. The rubber should just barely contact the mirror surface. If you can slip a piece of paper between them and the mirror, that's about right.

These adjustments and more are described in detail on the Skyquest-telescopes Yahoo group at:

http://groups.yahoo.com/group/skyquest-telescopes

Jeff Chappell

Go for the 8" and save for the accessories later. You can always add the accessories, but you can't add aperture.

Heck, why not skip lunch for a month and get the 10"?

Don, where did you get the low profile adapter? I too got the Burgess corrector lens for my XT10, but was disappointed to find that I'm still about 1/8" short of being able to come to focus.

Jeff

ROBERT MOORE said:

WOW Thank for your help I did not know anything about EQ. Platforms but after look at that site it just may be the way to go...... what is involved in the seting up of an EQ.platform?

Bob

Not much, especially if you're just going to be using it visually, and not expecting to do any long exposure photography. Just set it on some level ground (use a bubble level to make sure) and point it towards the north celestial pole. Set your scope on top of it and turn it on. That's it.

Since equatorial platforms can't rotate more than 15 degrees or so, they can only track for about an hour, after which you release a clutch or lift the top platform off and return it to the starting postion (it depends on the method of design). Then you just start over again. It only takes a few seconds.

Jeff

Dannon,

How about checking to see if there are any astronomy clubs in the Denver area that have loaner scopes available? Our club, for instance, has a number of dobs up to 10" that we allow members to check out. Even if you had to join the club, that might be your cheapest option. Our annual dues are only $24. Unfortunately for you, we're still about 700 miles from Denver.

Jeff

Jim,

I had the same problem with the Burgess BV and OCA in my XT10. I added this 1" barrel extension that I got from ScopeStuff for $19 and it works fine, although it will increase the magnification of the OCA a little bit.

Hope this helps!

Jeff

http://www.scopestuff.com/ss_epe2.htm

Floyd, yours and mine could be twins. That's the closest I've ever seen to ours in terms of color and expression. Ours is a female, and you're right, they are awesome dogs.