Posts Made By: Bill Meyers

Hi, all,
I am posting this here because the phenomenon occurs in a reflector in my case, and there appears to be the biggest density of optical gurus on this forum.

I noticed the phenomenon while looking at Rigel and Sirius through my 16 inch f/4.0 reflector in slightly hazy skies. Rigel and Sirius were both surrounded by zillions of little bright spikes, like diffraction spikes from a disgonal holder but very much smaller and almost infinitely numerous.
This is quite different from the intense round image I was used to on Vega with my 11" reflector.

The phenomenon is not discussed in Rutten and Van Rooj. I don't have Suiter, but I have never seen it illustrated in any article on star testing. It appears not to be discussed in any book I can find and in no web article. It took me two hours with Google to even find out its name: "radial spiking."

I can find only two referecnes to it, one in a Sky $ Telescope article in Sept. 2005 issue, p. 35, the only issue I don't have from that year. The other is a set of posts by Ed Zarenski on CN in the binocular forum. This defect is apparently characteristic of some binoculars.
There is no real explanation given, but Ed, whom I respect, says it is caused by a lens (or occasionally by reflections from a binocular prism.)

An optical friend of mine suggests it may be caused by my eyepiece.

The eyepieces in question are a 13E and an 8E, both used wiht a Paracorr. The telescope mirror tests as essentially perfect, and the scope was colllimated using a Howie Glatter 2 inch laser colllimator plus a Blug. The focuser is a Feathertouch.

It's hard for me to see how any of the above could have caused the problem. The magnifications with the 13E and the 8E were 140x and 233x respectively.

Because of the image defect, Rigel B was surprisingly difficult for me at 140x although I saw it after my spouse pointed it out. At 233x it was much easier. But not as easy as it has previously been in my 6"f/5 reflector.

Problems were less on dimmer stars. The E star in the Trapezium was easy.

As the mad scientist that I am, I came up with all kinds of ingenious theories that the defect was in my eyes, until my wife pointed out that she saw the radial spikes too and remarked on how obtrusive they were.

I am sure this phenomenon is due to some simple thing I am overlooking, and I welcome any suggestions. Thanks in advance,

Bill Meyers

Hi, all,
I have been experiencing a strange eyepiece phenomenon, in a variety of eyepieces, in a variety of Dobsonian reflectors, and this has been seen by two other experienced observers in their own telescopes with their own eyepieces.
I think this rules out factors related to a specific observer, or a specific eyepiece, or a specific telescope, or collimation.
What I see when I look at Jupiter in the center of the field of view of my eyepiece (I use mostly Ethoi or Naglers) and my eye centered over the center of the eyelens of the eyepiece, is a circular glow surrounding the planet, but when I position my eye so that I am looking at Jupiter through one side of t he eyepiece at an oblique angle, Jupiter is surrounded by black sky.
Any suggestions as to causation?
Thanks,
Bill

Somewhere on the web, I think in usenet but I am not sure, I saw a posting or series of postings by someone who visited the Synta factory. Perhaps a Google search would turn it up. Sorry to be so vague,
Bill Meyers

Hello, Tgm,
A few more alternatives you could check out:
An 8 or 10 inch Mag1 Portaball. Very small, portable, Zambuto optics. Considerable wait time though. And expensive.
An 8 inch Starbuckets ultralight. Looks good, short wait, but expensive.
A 6 inch f5 from Stargazer Steve for widefield richest field telescope work. Not expensive.
A Plettstone 12.5 or 15 inch.
Maybe someone could make you a version IV of Albert Highe's 12.5 inch scope. Total weight 40 lbs.
Hope this helps,
Bill Meyers

Hi,
Maybe consider an 8 inch f5 or f6 Portaball, an 11 inch Starmaster ELT, an 8 inch f5 or f6 Starbuckets, or a 6 inch f5 Stargazer Steve scope?
Bill Meyers

Hello, Hal,
My observing group uses glfs (green laser finders)the same way yours does. We find them very helpful.
The problem can be idiots at star parties who are irresponsible in using them.
At true dark star parties, which people travel great distanfces to attend =such as the Shingletown Star Party on a remote mountain site in Callifornia --I flew and drove there from Cincinnati a great star party by the way -- they were banned on aesthetic grounds, and rightly so.

I used to use a glf as my preferred method of pointing the telescope, especially in suburban skies where there are not enough vusible stars to make star hopping via a Telrad or optical finder feasible. But this was when I was observing alone or with a small group of friends who did not mind.

Now I use the glp only to align my Sky Commander on two stars; after that I use the Sky Commander.

If one searches the annals of s.a.a. you will find threads hundreds of posts long, in which I was a defender, often nearly alone of the glp when used to observe alone or with a small group of agreeable friends. One problem was that people refused to acknowledge that as one grows older, one's spine gets stiffer and one cannot as easily twist and contort, even to look through a Telrad with its great eye relief.

You sound like a most interesting guy. How many people play Mozart and maintain a classy motorcyle? Not many.
Good luck with your new scope,
Bill Meyers

Hello, Dave,
Good to hear from you. Can you give us more detais: what kind of laser did the damage, how long was the exposure, who was the laser sales person, how was the damage inflicted, how long ago was the incident causing the damage, and what are the after-effects and how long have they lasted? You have a lot of credibility here so it would really help us to hear more details from you.
Thanks,
Bill Meyers

Michael,
See my post to Floyd about innovative designs.
Regards,
Bill Meyers

I have the 24 and have used it for years. A great eyepiece. To supplement it I skipped the Panoptics, which I hear are a bit better, and went directly to a 20 Nagler2 with its 82 degree field, a great eyepiece unfortunately now out of production. But I am also very happy with the 24 which is much lighter and hence very convenient on smaller socpes.
Bill Meyers

Hi, Alan,
A most astute query, as might be expected from you.
My take on this is that perfectionism, fantasy expectations, love of tinkering, and an increase in sophistication are involved in the usual progression of equipment ownership.
An AP Traveler often spurs a yearning for an AP 130, which spurs a yearning for an AP 7 or 8 inch, etc. A TMB 80 spurs a yearning for a TMB 115 or 130, or a TEC or TV 140, etc. This trend can be observed on the AP and TMB yahoo groups.
Similarly perhaps with Dobs. But with Dobs the human life cycle is also involved: Dobs grow larger from the early years into middle age, then smaller as aging sets in and one cannot handle such a large scope.
It would be nice if people could find a scope they love and stick with it for a long time and concentrate on enjoying the sky. As I have with a 6 inch f./5 for twenty years, and now an 11 SM ELT f/4.5. My wife has a 10 inch CPT which she adores.
I hear of so many people who own 8 telescopes, and I think of how good and satisfying a scope they could have afforded if they had bought just one or two really good ones.
Thanks for the stimulating post,
Bill Meyers