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Posts Made By: Mark Costello III

January 26, 2010 01:44 PM Forum: Refractors

Star Diagonal Service Life

Posted By Mark Costello III

Hi all,

I've had an enhanced star diagonal for almost six years that I've used for about 600-900 hours. Having recalled reading a post here that enhanced star diagonals will degrade over time, I'm wondering if it's time to replace it. If its reflectivity out of the box was 98% (it's a 2004 William Optics 2" diagonal), how long would it take for it to deteriorate to a reflectivity of less than 87%?

If I have to replace it, I'll do it with a dielectric star diagonal which I understand won't deteriorate significantly over time. Is this correct?

Thanks in advance for your responses and advice.

Mark Costello
Matthews, NC

August 2, 2010 06:12 AM Forum: Refractors

Re: New DSO-refractor email group

Posted By Mark Costello III

Thanks for the tip. I'm in ... I and my ES AR127.

February 2, 2011 01:51 PM Forum: Deep Sky Observing

Area around Mirfak

Posted By Mark Costello III

This area seems to be loaded with bright stars. I find it as pleasing to observe at low power as M45 and M44. Is this field of stars a cluster or just a bunch of stars that appear close together. Has it a name?


Mark Costello
Matthews, NC

February 28, 2011 02:18 PM Forum: Deep Sky Observing

Something I didn't expect....

Posted By Mark Costello III

I was out last Saturday with my relatively new 5" achromatic refractor (achro), an Explore Scientific AR127. I took advantage of the moon rising late to observe and draw some deep sky objects. One of them was M35. I also went looking for nearby NGC 2158. I couldn't quite see it at 26X (Celestron Ultima 31mm) or 103X (Baader Hyperion 8mm). So noting that this complex was in nearly the best position it could be (close to zenith) and really wanting to see if I could see NGC2158, I went for 206X (inserting a TV barlows lens). Much to my surprise, it worked. I was able to see a grainy haze with individual stars winking in and out. I also tried this on Cluster NGC 2420 and found that the view was better at 206X than 103X. Ditto with NGC 2392 (the Eskimo Nebula).

I've had this experience before with M11 the Wild Duck Cluster. The question I have for y'all is this: From way back in the late 60s reading Edmund catalogs, I had always thought that deep sky objects (DSOs) should be viewed at low to mid power. Yet for a few of them, it appears that high power seems to work even to the point of making them "brighter." Is this correct, or should I stick to low or medium power for some DSOs.

Thanks for your response....

Mark Costello
Matthews, NC

May 12, 2011 11:04 AM Forum: Politics

How Brave of Them

Posted By Mark Costello III

The title line is written "tongue in cheek."

August 16, 2011 02:04 PM Forum: Deep Sky Observing

A Question for Those Who Observe with Smaller Tele

Posted By Mark Costello III

I'd like to throw this out for those of y'all who spend a fair amount of time observing with telescopes 6" or smaller. Last night, I spent maybe an hour, hour and a half in Ophiuchus, divided about equally between Globulars M10 and M12. Observing both with a 5" refractor, at times it seemed that there was a thin spray of stars that could be seen across the face of each, particularly at 206X. Also, at both 103X and 206X, it seemed that I could see a spray of stars around them. The background material on these clusters indicate that they are a bit loose for globulars. So I wasn't too surprised to see some individual stars in and near them. But I thought I'd ask: Has anyone gotten this type of partial resolution (or better) with a telescope of similar size?

Thanks very much.

November 17, 2011 02:01 PM Forum: Politics

Bad News for Boomers?

Posted By Mark Costello III

I saw this on the internet.

Personally, we (my wife and I) have a good bit more saved than the $25,000 mentioned in the article but probably not enough to retire at 65 or 66. It's a combination of (1) me not saving enough for retirement at that age, (2) my company replacing its pension program with a retirement balance plan and cash retirement plan (I've contributed some to this account), and the economy going to pot starting in 2008....

December 5, 2011 02:04 PM Forum: Religion

Music for Christmas - 1

Posted By Mark Costello III

This will be part of the Christmas concert at our church, sung by a youth choir.

Here is a translation of the lyrics.

Merry Christmas....

December 9, 2011 11:02 AM Forum: Religion

Music for Christmas - 2

Posted By Mark Costello III

Here is a three movement piece that was part of our church Christmas concert 10 years ago. We hired the strings and woodwinds but the organist and brasswind players were part of our fairly deep bench at our church. This rendition is from the musicians and choirs at a Catholic church a bit down the road from where I live.

When I'm out under the stars with my 5" achro refractor, this is one of the pieces sort of playing in my head. I wonder what it was like when the night sky lit up that night on the first Christmas.

Merry Christmas

December 14, 2011 06:19 AM Forum: Off Topic Discussions

Shuttle replacement

Posted By Mark Costello III

Seeing this reminded me of these space travel shows I saw as a very young kid and helped me choose engineering as a profession....