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Posts Made By: Howard Knytych

January 21, 2004 12:20 PM Forum: Religion

State of the Union Address

Posted By Howard Knytych

I don't think it's gall for GWB to define marriage. As president, he's using the power of the bully pulpit. Realistically, and politically, it comes with the territory. It's unfortunate, but since GWB has a bullhorn, he's gonna use it.

March 22, 2004 04:12 PM Forum: Deep Sky Observing

Jovian shadow transits

Posted By Howard Knytych

Those black dots across the face of Jupiter are pretty small. Assuming you can push your magnification 50x per inch, the best you could reasonably expect under good conditions is about 225x. If you say your collimation's off, I'd reduce that by a percentage of, say, 25%, which would bring it down to 165x. Your image would also be darker as you push the magnification, and you'd want to maximize contrast as much as you can. Your best view would be a compromize somewhere between high magnification and the contrast you'd get with lower power. Unless you've got young eyes, I'd recommend hanging out with someone with more aperture to guarantee seeing the transits. But keep your scope handy and see how it works!

Good luck!
Howard

March 25, 2004 10:16 AM Forum: Equipment Talk

Collimating a 12.5 F5 Newtonian

Posted By Howard Knytych

A cheshire enables you to align all elements of the visual path, including the focuser with the secondary, the secondary with the primary, and the centering of the primary. A laser collimator can enable the latter, aligning the return of the center dot back to the collimator in the focuser, but it does not address the focuser/secondary alignment or secondary/primary alignment. You can have a systematic alignment error in those with no indication, using a laser collimator alone.

I use a cheshire to perform all alignments visually, then verify the collimation with the laser. This is on an 18" f/4.5 system. If they disagree, I'll go thru the process a second time until the results using both the cheshire and the laser are close. I don't insist that the laser be dead-centered on the center dot of the primary. Through experience, when the results vary a bit, I've learned to trust the cheshire more.

Good luck,
Howard

April 8, 2004 05:28 PM Forum: Politics

April 15, 2004 03:49 PM Forum: Beginning Astronomy?

Mounting a Telrad

Posted By Howard Knytych

There's really nothing to it:

The near end of the Telrad which faces you has three knobs for adjusting the placement of the bullseye reticle, so you have plenty of "wiggle room" for aligning the telrad image with your view thru the eyepiece. As I recall, padded sticky tape comes affixed to the Telrad base. Just carefully eyeball the parallel placement of the Telrad on the tube of your scope at a convenient location, lining it up parallel with the optical path of the scope as best you can visually. Reasonable care should be sufficient; as I said, there's plenty of available adjustment. What's actually more important is determining the best placement for the Telrad. You don't want it to interfere with your head as you view thru the eyepiece, yet you want it to be easily accessible to look thru. I'd suggest trying several positions of the entire Telrad unit on the optical tube prior to committing yourself by removing the protective backing off the tape. Once you determine where you want to place the Unit, you might want to make little pencil marks on the optical tube to guide you when you press the base with the tape onto the tube.

Whenever you mount the main part of the Telrad prior to an observing session, just swing the scope onto a stationary object, like a treetop or mountaintop during the day, or polaris at night. Using your widest angle eyepiece, sight in the top of the tree or whatever, then tweak the three adjustment knobs on the back of the Telrad to align the bullseye display with what you see thru the scope eyepiece. Use the same procedure to align an optical finder that magnifies as well: First put the scope on a known stationary object, then adjust the finder.

April 22, 2004 01:11 PM Forum: Off Topic Discussions

stress level

Posted By Howard Knytych

I'm in serious stress - I guess I really need that vacation!

April 28, 2004 02:07 PM Forum: Politics

May 6, 2004 04:49 PM Forum: Equipment Talk

Russell Optics 65 & 85 mm EP

Posted By Howard Knytych

I suggest viewing the North American nebula by using a good pair of binoculars with a generous objective end, say 12x60 or so, under dark skies. For me, they seem to work better than wide angle EPs on a scope. With practice, using the binocs, you can later see it with the naked eye if your skies are good. You're right on with the Veil or Pleadies, however.

May 26, 2004 08:40 AM Forum: Politics

Where Have All the Liberals Gone?

Posted By Howard Knytych

In case you hadn't realized, during this past weekend, the moon was new or crescent. This forum is, after all, in an astronomy-based url. We liberals have lives -- some of us have been out collecting DSOs. smile

May 31, 2004 09:27 AM Forum: Politics

800 Faces

Posted By Howard Knytych

As I watched, I kept thinking that behind each face was a life - hopes, dreams, career, family ties, loves, accomplishments, history - all snuffed out.