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Posts Made By: David Simons

May 22, 2005 03:18 PM Forum: Deep Sky Observing

NGC 5139 (Omega Centauri)

Posted By David Simons

Has anyone found this one yet this year ? I actually took a stab at it last night, and think I saw a dim blob in the glare of the almost full moon and horizon glow. The blob was almost exactly near the two dim stars as indicated on the chart from "The Sky" below. I was only using a 5" f8 refractor around 40x. With a normal night, I think it would have been plenty, but with all the light wash I think I should have had around 8" It was on the very edge of detection.

June 25, 2005 01:05 PM Forum: Telescope Making

50lb Hunk of Zerodur (Cervit?)

Posted By David Simons

Just what I need, another project .. 8)

This is a 1/3 "section" of a 25" f4 mirror. It is 4" thick and weighs about 50lbs. Any ideas on how to do a quick mount for star testing this beast ? Also anybody have any thoughts whether this should be masked for a circular aperture, or just let it be the way it is ?

Thanks !

July 11, 2005 11:56 PM Forum: Deep Sky Observing

Stock 2

Posted By David Simons

I was admiring the star chains in the Double cluster area, and I followed a long chain of stars up towards what became a thick cloud of glittering stars. Nothing was listed on my Cambridge Atlas, so I went to Desktop Universe and pulled up "Stock 2". Not the most memorable name, but the big open cluster looked great in my prototype 9" f4 triplet refractor at 40X and 2 degrees FOV (surplus simulator lens). Does anybody else have any impressions of this cluster ? (shown at the top of the screen) It needs a wide field to look good. Big bino's in a dark sky should work well.


August 9, 2005 03:39 AM Forum: Deep Sky Observing

Objects in Cygnus

Posted By David Simons

I was relaxing last weekend panning around in Cygnus with some 50mm bino's and was scanning by all kinds of interesting star chains, circles, dark areas, Milky Way patches and what might be big clusters.

Other than the usual references to relatively small objects, are there some sources for these "bigger" objects? FOV on my bino's was about 6 degrees.

Anybody have any favorites in this area ?

August 17, 2005 10:06 PM Forum: Deep Sky Observing

Observing forms

Posted By David Simons

I stumbled onto a link to a decent observing form on the Skywatcher web page.

http://www.skywatchertelescope.net/Downloads/ObservingForm.pdf

Does anybody else have or use some good observing forms ?


December 22, 2005 12:46 AM Forum: Pictures of Me and My Telescope and........

8.9in vs. 9.25in

Posted By David Simons

I had some fun comparing a classic C9.25 with the old style digital counter wheel focuser and a vintage TSC225 on my new side by side mounting plate.

I'll try to post a mini-review later after the Holidays.

January 3, 2006 10:49 PM Forum: Pictures of Me and My Telescope and........

A Tale of Two Taks

Posted By David Simons

I recently acquired a Losmandy dual mounting plate, and have been having some fun doing side by side comparisons of scopes last November. On the right is a 225mm Tak SCT (TSC225), and the left is a 152mm f8 refractor (FS152). I was looking at Mars in November, and the refractor would give the more consistently sharp views, while the SCT would give generally less detailed views until the seeing or cool down would even out, then the SCT would give a lot of detail in fleeting moments but you had to be patient. I have a fan for this scope that mounts in the back, and will try it out next time when we aren't getting pounded with rain.

January 4, 2006 02:30 AM Forum: Astro Binoculars

Going Wide

Posted By David Simons

I recently received an old pair of Tasco 7x35, 11 degree FOV bino's. Although very small eye relief, I had to practically put the glass onto my eye, the FOV was impressive. For a few hours we had an unusually dark, transparent sky here in N. California after a rain, and cruising the Orion, Puppis, and Canis M regions was a real treat. Little globular clusters floating on a sea of filmy Milky way. The whole bottom of Orion was visible in one view, belt stars to Rigel with M42 in between. Although 35mm is generally not considered a deep sky aperture, I was sure having some fun!

Does anybody else use a pair of these old bino's ?

January 10, 2006 12:54 AM Forum: Refractors

5 inch Fluorite

Posted By David Simons

A few years back I happened upon a used Takahashi 128mm f8 fluorite doublet lens ( a few sleeks in the coating from over zealous cleaning). I had planned to eventually buy the tube, focuser rings etc. from Texas Nautical.

However after getting the lense cleaned by one of the opticians at work, he decided to do a cross polarizer test on the lense. I had seen annealed optical glass under this test and wasn't expecting much, but we saw a velvety pattern suspended inside the lense, and also the shadow cross shown the picture. I have heard the shadow is not unusual, but the velvet pattern was unexpected.

Does anybody have some thoughts on this type of effect? The Tak fluorite doublet gives crisp pinpoint stars and of course nearly zero color error.

January 30, 2006 11:09 PM Forum: Telescope Making

A Wide Angle Finder

Posted By David Simons

I have been using my 20X Vixen Big bino's for a few years now, but need a somewhat unique finder. The bino's give a 3 degree FOV. Although I have used a Rigel on it, I occasionally find myself in a sky area without enough bright stars to start the Rigel from, and need a few more stars to align to. I also have a 6X30 correct view finder, but the FOV is not a whole lot bigger than the bino's.

So for fun I modified a 45 degree diagonal by adding a 25mm binocular lense inside the front tube of the diagonal. This allows a 25mm Plossl to focus, and gives a correct view, 4.5X, 11 degree FOV, very long eye relief finder. Although there is some edge of field illumination drop off, the view is very nice. It pulls in the little mag 7 and 8 stars that allow easy star hopping and alignment to a star chart. It fits inside the Chinese finder scope mount pretty well also.