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Posts Made By: Thomas Holst

March 1, 2009 11:44 PM Forum: Beginning Astronomy?

Nexstar 8 Question

Posted By Thomas Holst
Paul,

Shortly after I bought a C8 for my daughter several years ago, we found the need for a good 2" mirror diagonal to replace the original cheap 1-1/4" prism diagonal. I ended up buying her a William Optic 2" SCT mirror diagonal for about $130 new. (see attached photo) This WO diagonal was very nicely made, came with 2" to 1-1/4" adapter, has brass compression rings and a large ribbed ring which screwed directly onto the back of the C8 (after removing the visual back). This attachment system makes it easy to rotate and lock the diagonal to a different position.

This was not the expensive 99% reflectivity, dielectric, carbon fiber SCT diagonal that WO currently makes, but it still performs very well and is a nice addition to the C8. I would guess that you could find a used one here on Astromart for a very reasonable price.

As for the crayford focuser, we elected to live with the little bit of image shift using the stock Celestron focusing system. For visual use it's not that big of a deal.

Just passing this info along in case you're looking to keep costs down.

March 2, 2009 12:34 AM Forum: Guns and Hunting Optics

Ready for a composite revolver or shotgun?

Posted By Thomas Holst
Lee Spain said:
It looks like Ruger has a new .38 snubbie revolver made of composites and stainless steel. It's called the LCR...
...What do you guys think of composite stuff?

I guess I'm just old fashioned, but I think revolvers should be all metal. Besides, the Ruger LCR 38 Spl. at 13 oz. is still a full ounce heavier than the S&W Model 360PD, which is a .357 Mag. 5-shot revolver, made of alloy/titanium/stainless steel. This makes the Ruger LCR rather pointless.

When it comes to a small, concealable, defensive weapon, I'm still sold on my little Glock 36. Yeah, it's heavier than a small 5-shot revolver, but it's a full 1/3" thinner, only 1/2" longer, and carries 7 rounds of .45 ACP hardball ammo.

March 3, 2009 01:14 AM Forum: Bad to the Bone Autos

87 Subaru Brat

Posted By Thomas Holst
Still have the seats in the back?

March 4, 2009 12:08 AM Forum: Politics

H.R. 45 The end of the 2nd Amendment?

Posted By Thomas Holst
The crazy thing about legislation like this is that it perpetuates the illusion that you can control those who don't follow the rules by making more rules. More restrictive rules only serve to harass law abiding gun owners while criminals continue to do what they've always done - whatever the hell they want. Bad guys and crazy people will simply continue to beg, borrow or steal (emphasis on steal) firearms to do their dirty work.

For those not aware, HR 45 was named for 16 year old Blair Holt, who was murdered by a 16 year old gang member on a city bus on the South side of Chicago. The killer used a borrowed .40 cal handgun.

Now you tell me if HR 45 would have prevented that.

March 4, 2009 08:20 PM Forum: Guns and Hunting Optics

Dumb .223 Rifle Questions

Posted By Thomas Holst
James C Chandler Jr said:
...is there a difference between .223 Rem versus 5.56mm ammo for these things?

James,

There is no practical difference. The .223 Remington cartridge is the civilian version of the 5.56 mm NATO round. This relationship is similar to the .308 Winchester round being the civilian version of the 7.62 mm NATO round. In both situations, the civilian round and military round are interchangeable in a rifle chambered for that cartridge.

For more information, look here: http://en.wikipedia.org/wiki/5.56x45mm_NATO

March 5, 2009 09:48 PM Forum: AstroMart FAQ

why not ship to Canada??????

Posted By Thomas Holst
Jim,

My only problem with doing business with Canadians has been the very slow and inconsistent mail service. Mail that takes 2~3 days within CONUS takes weeks or a month to/from Canada. I've mailed stuff to Finland, Poland and Chile and had it get there faster. What's up with the mail service?

March 7, 2009 12:47 AM Forum: Star Parties

Star Party Question ? just looking for input ....

Posted By Thomas Holst
Gary Cislak said:

...What kind of interest would you have in an Apollo Moonwalker as being a Keynote speaker at a Star Party?...

Gary,

I think I can give you some first hand experience with that. I'm a third year VP of the Boise Astronomicial Society and our biggest event of the year is the Idaho Star Party, held each September at Bruneau Dunes State Park in Southern Idaho.

This past September we managed to get Barbara Morgan (backup Teacher in Space to Christa McAuliffe who was lost in the Challenger disaster) as one of our guest speakers. Barbara was the teacher from McCall, Idaho and was selected for the TISP in 1985 and it was 22 years before she actually flew as part of the crew in STS-118 on the Endeavor in August of 2007.

In 2008, Barbara left NASA and accepted a position with Boise State University (remember the 2007 Fiesta Bowl?). We jumped at the chance of having a real live astronaut at our event and she graciously accepted our invitation. It turned out to be a good decision as the room we used for her talk and Power Point presentation was packed - standing room only. After 1-1/2 hours, we had to vacate the room, so Barbara came to the campground shelter, followed by most of the original audience (including many families with kids) and she answered questions and chatted with us in the dark for another hour. It was the best turnout for a guest speaker we've ever had. There's nothing like having someone who's "been there and done that".

March 14, 2009 05:21 AM Forum: Coronado-Lunt-DayStar Solar Filters

Coronado PST newbie needs advice

Posted By Thomas Holst
Jay Martin said:

...Basically, I am seeing a big reddish looking smooth ball. (No detail or activity on the edge)...

Jay,

What eyepiece are you using? The basic PST kit comes with a 25mm eyepiece, which in my opinion doesn't give you enough magnification to see much detail. Try a 12.5mm or 10mm Plossl with a good rubber eyecup and see if that gives you a better view. (A 12.5 will allow you to still see the entire solar disc.) Also, some days the sun has little or no prominence activity. Give it a few more tries over time, adjusting the focuser first and then slowly adjusting the tuning ring until you see some edge detail. Average prominences through the basic PST will be small, faint filaments.

In my experience, on a good day, you should be able to see edge detail similar to this photo: http://www.buytelescopes.com/viewphoto.aspx?pid=3834&p=6580

April 7, 2009 04:29 AM Forum: Telescope Making

Calipers & Micrometers

Posted By Thomas Holst
James,

Not owning any digital measuring devices, I can't help you in that respect. I do own an SPI (Swiss made) green plastic 6" dial caliper and it's served me well for nearly 30 years for quick ball park measurements. It works fine for bullets. When I want better accuracy, I pull out my 33 year old Mitutoyo 6" dial caliper. The advantages to the dial calipers are a.) no batteries and b.) they are easily zeroed are instantly adjustable.

For critical measurements, there is no substitute for a good micrometer. I've got four of them - all Starrett, and all are way older than I am. The advantage to these high quality micrometers is that since they are adjustable for thread wear, they last almost forever and the thimbles can be re-zeroed.

Rather than settling for a new cheaply made micrometer or dial caliper, I'd suggest searching the used tool stores (or relatives) for oldies but goodies, clean them up, check them and put them to work. Old instuments made by Starrett, Brown & Sharpe, Lufkin and not quite so old Mitutoyo's are far better made than the Chinese stuff and are a great value.


April 8, 2009 11:39 PM Forum: Equipment Talk

36" refractor with TV 55mm. Plossl

Posted By Thomas Holst
John,

Thanks for sharing the photos of the Lick Observatory and the 36" refractor. I took me back to my early 70's college days at San Jose State, when I took many motorcycle rides up the to top of Mount Hamilton to see the observatory. I never had the opportunity to look through the instrument myself and only got to see it through the window in the door at the entrance into the dome from the main hallway.

On one visit, the movable observation floor under the dome (moves up and down 16' on hydraulic rams) was in the raised position and I could see where the scope's mount was anchored to the exposed rock of the mountain. A single light bulb illuminated a bronze plaque on the base of the mount; "Here lies the body of James Lick". He must be the only person on Earth, buried under a telescope.

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