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M20 Trifid Nebula in LRGBHa

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Posts Made By: Bob Chester

September 23, 2005 05:33 AM Forum: Telescope Making

All Those Spherical Mirrors

Posted By Bob Chester
Hi folks,

We get lots of discussions about the quality of figure and smoothness of parabolic mirrors. And the benefits of having a newt. primary re-figured by a pro.

Why so few similar discussions about the mirrors in all those designs utilizing spherical primaries? Primarily the mass produced SNs and SCTs. Certainly they too should benefit from a good re-figure.and would be easier to test.

Why have I never read a post about how great a SCT or SN performed after having its mirrors re-figured?

Any glass pushers out there done it?

Anyone ever had one re-figured?

I have ground a few mirrors and am confident in my ability to produce a very smooth sphere. Would I be wasting my time in attempting to make a 'premium' SN or SCT out of one of the mass produced OTAs? OR, does the mass produced corrector plate prevent me from ever reaching 'premium' status.

Yep, I'm contemplating a new project.
Bob

October 16, 2005 08:41 PM Forum: CCD Imaging and Processing/Solar System

Small scope afocal Mars

Posted By Bob Chester
I just had to see what was possible. I got a little more than I expected. Though nothing special.
Bob

May 12, 2006 11:14 PM Forum: Eyepieces

Re: What are your 3 most used eyepieces?

Posted By Bob Chester
With astigmatic eyes and a modest EP collection (I still have a wish list).

FS78
24mm TV widefield
15mm TV widefield
3-6MM TV zoom

6" newt
19mm TV widefield
7mm Meade RG ortho
3-6mm TV zoom

10" dob
24mm TV widefield
26mm B&L pro plössl w/TV 1.8 barlow
7mm Meade RG ortho

That being said I think the 3 best performing eyepieces in my collection are:

26mm B&L pro plössl
19mm TV widefield
7mm Meade RG ortho

Bob

May 13, 2006 05:52 AM Forum: Off Topic Discussions

Characters

Posted By Bob Chester
For those who haven't discovered the character map on their PC (windows) and would like to use them. Here are a couple of astro useful characters.

Hold down the alt key while typing in the numbers.

Umlaut, ö , as in plössl = alt + 0246
Degree, ° , as in 82° Nagler = alt + 0176
and a fun one
ƒ, as in ƒ/8 = alt + 0131

Have fun, Bob

August 21, 2006 05:54 AM Forum: Pet Pics

Goodbye old friend

Posted By Bob Chester
Joba, our 21 year old female was put to sleep on Tuesday.
Very smart cat but very anti-social. Hated females and children to the point of attacking them. My daughter and her baby sitter had to call the police one Halloween to come baracade the cat in a bedroom. Trusted, played, wrestled and slept with me and as evil as she was, she got more affection than she ever desired or deserved. A long good life for a cool evil cat.

She was 18 in this photo.

September 11, 2006 08:07 AM Forum: Pictures of Me and My Telescope and........

Re: 10" Newtonian.....Finally Finished

Posted By Bob Chester
David,
Beautiful, you've assembled yourself a world class instrument, very nice indeed!
Bob

September 12, 2006 02:29 AM Forum: Telescope Making

Structural Integrity Question

Posted By Bob Chester
Hey gang,

Concerning Newtonian tubes, be it sonotube, aluminum, or whatever.

How much material can be removed by drilling holes or cutting a lattice pattern in the tube before structural integrity is compromised or flex is induced.
And, any ideas as to what pattern would be best?

I'm just daydreaming about lightweight tubes.

Bob



December 7, 2006 04:51 AM Forum: Off Topic Discussions

Gettin' Old

Posted By Bob Chester
Well, it finally happened. At 1:55 pm Pacific time Dec. 5, 2006 I became a grandfather for the first time (and according to my daughter, the only time). At 52 I feel way too young to be a gramps but, considering my daughter is 29, it could have easily happened 10 or more years ago. Being 1500 miles away, I have to wait till Christmas to meet him in person.

Here is the young Jedi master Lucas Peter Franklin.


Babys is kool

January 19, 2007 11:11 PM Forum: Equipment Talk

Re: Pick & Pluck Foam is Hard to Find!! Why??

Posted By Bob Chester
Michael,
Doskocil sells replacement foam for thier cases. Check out this page to see if the size of your case matches and click on replacement parts to find the foam.
Bob
http://doskosport.com/Catalog.plx?ID=4

p.s. I have one of these cases and the foam set includes 2) 2" thick pieces of pick and pluck ,1) about 1/2" thick for under the pick and pluck and a piece of eggcrate for the lid.

July 9, 2007 04:54 AM Forum: Off Topic Discussions

Severe Vignetting?

Posted By Bob Chester
Nope... 4th of July fireworks with a stellar look to it.

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