Posts Made By: Joseph Babendreier

I won an auction for an old 3.1" secondary (no coatings). [email protected] sent me a message saying:

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I contacted the seller by sending an email, using the email address included in the [email protected] message notifying me of the auction transaction.

It's been more than 48 hours since I did that, without receiving any reply.

Maybe my emails are not reaching the seller. I have no idea how to send the seller with a PM thru Astromart. I tried to type his name for sending a personal message and Astromart indicated that I could not send this person a PM.

What should I do?

Clears,
Joe

I picked up a (slightly damaged) 17.5" mirror in a sale (dirt cheap). The guy insisted it was a Coulter. How he was sure, I don't know. I didn't get a chance to ask.

It's has a f/4.5 ratio, which I measured myself.

Anyway, the side of this 17.5" mirror has a marking:

Jason Stahl #788 -5

The -5 is circled.

Does that mean anything to you?

Clears,
Joe

I noticed last night when I was collimating my 10" dob that there are some blotches near the edge (about 1" wide along on the side of the mirror that sits lowest in the mirror box when viewing). More than blotches, they are areas where the surface is no longer giving full reflectivity and they look a bit yellowish.

Any ideas on what's happening?

I tried cleaning the mirror (not that it was especially dirty -- just some dust) but nothing changed.

I have no idea how old the mirror is, since I bought it second-hand, but the mirror does have the number 1959 written on the back.

It's a 1.5" thick, 10" pyrex mirror.

Clears,
Joe

I started out here in Astromart at Christmas time a couple of years ago after hobbling together a telescope using an old 10" mirror set. My subscription to Astromart was a Christmas present! Somebody obviously though I needed some help in building telescopes

I posted a picture of the 10" scope I had built. Someone who saw it suggested I undo a few things and follow the classic dobsonian design for easier operation.

I finally got around to doing that. So I thought I'd post a picture. It's still the same "piece of junk" that I started with (trash can parts other than the mirror set), with several parts re-fashioned and re-arranged.

I'm mainly in a stall right now. I'm waiting for a friend in New York to bring me the 3.1" secondary mirror which I won in an auction on Astromart. With that mirror I'll be able to complete my new 17.5" dobsonian.

Clears,
Joe

There's a 48" Newtonian for sale on eBay. A mere $6 million.

That would make for a nice backyard scope, wouldn't it?

Better hurry, two offers have already placed!

Clears,
Joe

I just read about the total solar eclipse coming up on 11/3/2013.

I live in Nairobi.

The bishop of Lodwar (Kenya) happens to be a very close friend of mine, since I knew him before his ordination.

Should be interesting.

Clears,
Joe

I decided to completely overhaul my 4" refractor.

Since I had an old binocular already missing some pieces, I decided to try to use on of the 4 prisms to make a better star diagonal. (I had been using a cheapie $8 piece purchased new on eBay three years ago.)

So I cobbled together something remotely resembling a diagonal using other spare parts from other objects.

I amazed at how well the prism performs for visual observation.

Not having much experience, I was wondering if it is quite common to use prisms in diagonals. Any comments?

Clears,
Joe

I don't often post in this part of the forum. But I was struck by the lengthy WOW signal discussion in the Astrophysics forum (which seems to have a prohibition about throwing in any religiously oriented comment). So I wanted to throw one in here.

What would seem natural is that a universe as big as ours would be populated with all kinds of living, intelligent creatures.

Perhaps many such exist. Then again, maybe not.

Either way -- whether they exist or not -- we are essentially "stuck" on earth.

Well, maybe not. Maybe all the wormhole stuff will come true. But with the science we have so far, it doesn't look even remotely possible. Indeed, any true form of messaging each other live seems utterly impossible.

We have not had much a chance to detect intelligent life. But we've had lots of opportunities to detect objects moving faster than the speed of light -- and there aren't any. Maybe that will change. But the "c" limit looks like a solid fact. And if "c" is the fastest anyone anywhere go move, well, then, we (and future generations) are stuck in this solar system.

I'm not sure what it says about God's plan for us, but it is a strange aspect of creation.

It's humbling to think that God gave us the ability to get some idea of just how big his creation is--immense, truly beyond measure--and yet, Star Trek notwithstanding, he has limited our ability to explore it.

Maybe that's another part of what we lost in the Garden...

Clears,
Joe

I think I pushed my 10" mirror as far as I could. The conditions were both clear and steady. I was using a 3mm Zhummel EP. Since the FL = 1118mm, that would be about mag = 375X. (I had collimated using a barlowed laser.)

I was viewing Saturn almost as zenith in the early morning after the moon had set. I could see the shadow of the planet on the rings (a first for me ).

I suppose that means the mirror must be good quality -- to give that kind of resolution. Or is this pretty common for dobsonians, no matter the quality of the mirror?

Clears,
Joe

I'm starting to wonder what the possibilities are for convincing some business man here in Kenya to buy and operate a unit that could aluminize small mirrors.

I would like to introduce some kids to the idea of ATM, but the big obstacle for us here would be having to send a mirror outside the country for the service.

Can anybody direct me to some company that sells units that do aluminizing?

Clears,
Joe