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Posts Made By: Doug Peterson

April 1, 2004 10:10 PM Forum: Takahashi

New 2004 Takahashi Catalog on-line

Posted By Doug Peterson

Has several pictures of the new retractable-dewcap FS102II.

May 1, 2004 11:44 PM Forum: Lost Contacts and Personal Messages

John D Horsefield -- found!

Posted By Doug Peterson

909 698 6549



May 4, 2004 02:06 PM Forum: Chinese Optics Imports

So what is the problem with the 102F6....

Posted By Doug Peterson

For those of us who came late, I gather that some people are upset about late, or very late, extremely late, deliveries, but in addition, what actually are the technical problems with those delivered? Is the baffling stopping down a problem? What is that problem? Spherical abberation, chromatic abberation, astigmatism? Are there people also happy with their scopes?

June 15, 2004 12:08 PM Forum: Equipment Talk

Circle T and other markings on oculars

Posted By Doug Peterson

Has anyone cataloged who these markings' manufacturers belong to? I assume Circle T was Towa, and V for Vixen, etc., but other than that these are becomming collectable there doesn't seem to be much info out there.


June 17, 2004 05:18 PM Forum: Equipment Talk

Finest Large Focuser?

Posted By Doug Peterson

I have my own opinion, what is yours? I am thinking of

AP 2.7"
AP 4"
Feathertouch 3.5"
TMB 3"
TMB 4"
Takahashi 2.7"
Takahashi 4"
Unitron deluxe R&P
Vixen 60mm
Vixen 100mm
William Optics 4"

there must be others....

July 3, 2004 09:47 PM Forum: Takahashi

Sky 90 I vs. II

Posted By Doug Peterson

So what exactly were the changes from the original Sky 90 to the current version?

August 13, 2004 04:26 PM Forum: Equipment Talk

Celestron C65 Maksutov

Posted By Doug Peterson

The two samples of this scope I tested had severely decollimated optics. Oddly, the glass itself didn't seem too bad: out of focus stars were round, with some correction error, but the secondary obstruction was off-center pretty much counting the image out even for casual terrestrial use. The mis-collimation was obvious to the eye looking down either end of the tube. While the obstruction looks small at the corrector, the baffle tube appears to take a bigger bite out of the center. One of the two had such an unsmooth focuser that it was impossible to focus without moving the image out of the field. The zoom is pretty awful too.

Okay, I shouldn't expect a Questar for 60 bucks. Unfortunately, as it is all glued together plasic (is it possible to injection-mold an entire telescope complete?) there is NO way to alter the collimation short of sawing it in half.

Anyone else?

August 15, 2004 04:34 PM Forum: Equipment Talk

Giant Binos 25x40x120mm

Posted By Doug Peterson

I have aquired an as-new demo pair of these and they actually are quite good. I believe they are originally sourced from:

The official importer of the website above,, doesn't answer emails. APM/Markus Ludes--who always answers emails--shows them on his website, but so far as I can tell they are not yet available in the US.

Anyone know anything about these?

August 17, 2004 06:01 PM Forum: Equipment Talk

Celestron 100mm ED Spotting Scope

Posted By Doug Peterson

Well the sample I looked at had some sort of coma, color wedge or tilt problem that caused flares where pointlike daytime glints should be. Too bad, the color and spherical correction looked promising.

The zoom ocular has significant kidney bean effect and goes unsharp off axis pretty quick, but if the primary image was clean this would be a best buy.

The Chinese need to discover QA, or Celestron needs to show them, since Celestron's SCs appear to be getting it.

August 31, 2004 09:12 PM Forum: Equipment Talk

Who the heck was Sam Brown (Edmund Scientific)?

Posted By Doug Peterson

I have the pleasure of working with an ex-Edmund optician and optical engineer who knew some of the old guys at Edmund, including founder Norman Edmund himself and met his co-author of all those great booklets on telescope optics and optical bench work, the mysterious Sam Brown.

In fact, my co-worker was once tasked with rewriting and upating the books and put quite a bit of time into it, but the project was cancelled due to copywrite costs.

With a generic name like that, I always assumed it was a house-name. But in-fact, it turns out he was a real person, a recluse who didn't work directly for Edmund, rarely left his house, but poured out these educational and hobby materials for Norman, and may have been an amateur astronomer himself. His output certainly would indicate that. He died some time ago, I am told.

As someone who grew up reading these booklets and wanting to build all those delicious projects, I want to know more.

Anyone else know the gory details?