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[-=CROMAN=-]

Hey guys...

What do you think about having a Meade etx-80 (goto) with a green laser acting as a guide scope? Sort of a poor mans goto. Is there any reason why this wouldn't work if all alignments were good?

I do realize that not all goto software is the same but the etx series had some decent reviews. plus i can get one on ebay for pretty cheap.

[Chicago Astronomer - Astro Joe]

Cm,

I don't fully understand.

Are you exploring using the ETX as a stand alone scope with a laser guide?

The EXT series are a decent quick set-up line of scopes, but won't compare with your dobs.

Elaborate please.

[-=CROMAN=-]

Exactly!

Using the etx to create a guide star with the green laser. Then aiming a dob at the guide star.

[Chicago Astronomer - Astro Joe]

I see.

Things about lasers I have discovered...

A 5 mW laser won't cut it. Too dim and you'll need a 30Mw at least. The Chicago Astronomer doesn't touch anything below 50...

Lasers are very sensitive to temperature and in the cold - useless. During the cold months I keep the laser in my layers and warm. I don't even contemplate attaching it to the scope.

I have had some success in viewing the laser beam in the FOV of the eyepiece while hunting targets down, but again...it's a 50Mw....and it was attached to the scope. Light pollution will also "absorb" much of the beam's light, diminishing your desired goal. And as you walk away from the direct line of sight of the beam, (behind), the beam gets dimmer and fainter.

Parallax is also an issue.

Even the slightest degree of angle deviation will cause the beam to "shift" off the target from the perspective of the main scope. It'll get you in the general area, but you will need to get the scopes as close together as possible in height.

I think overall, you will be disappointed in the results of this set-up.

And about the ETXs...

Nice little machines and can't beat the portability - but do not deliver the punch that dobs deliver. The focal length along with the small aperture will not display targets the way you are used to. Contrast is also a bit on the weak side.

We had a member years ago who had a ETX and the constant "chugga chugga" of the motor drives was comforting.

But...

I would try this experiment anyway if you do get the ETX.

[Paulie pchris00]

It's a clever idea, but as Joe points out, I doubt it will work in practice.

[-=CROMAN=-]

Idea AXED!

[RobbW]

Jun 24, 2011 7:58:08 GMT -6 -=CROMAN=- said:

Idea AXED!

Sheesh! You don't have to be so violent about it!

I'm sorry, did I say violent? I meant artistic. And as art, your violent act of axing a GLP guide scope to tiny bits is covered by the free speech provisions of the 1st amendment. Go ahead and AXE away, my good friend! And don't worry if the kids see it. Remember, it's art!

[-=CROMAN=-]

Sheesh! You don't have to be so violent about it!

I'm sorry, did I say violent? I meant artistic. And as art, your violent act of axing a GLP guide scope to tiny bits is covered by the free speech provisions of the 1st amendment. Go ahead and AXE away, my good friend! And don't worry if the kids see it. Remember, it's art!

[Chicago Astronomer - Astro Joe]

Hey...you dudes

Stop beating up on that....

Oh.....it's just an ETX.

Carry on.

[atomant]

Glad you didn't start a money pit on the ETX80.
The shorty 80 fract is a nice and compact, low maintenance scope.
The ETX has the famed Meade goto system.
But.....it's old design, if the electronics go, your scope is stuck.
Also try pointing that ETX up toward zenith.

The newer starter goto systems are more flexible, allowing you interchange equipment.
Using the ubiquitous Vixen-style dovetail system.

My recommendation, save the cash for gas money and get under dark skies.
You have a 10in scope; you'll be shooting fish in a bucket.
Get a nice star chart; slowly build up your sky knowledge by concentrating on one constellation and its delights at a time.
Get use to using your telrad, your right angle finder and eps.

You have a nice low power wide field ep, you also have a nice high power ep.
What you are missing is a "teener" ep. Start a cookie jar fund for a nice used premium "teener" ep.

[patrickm]

Jul 1, 2011 12:03:32 GMT -6 atomant said:

My recommendation, save the cash for gas money and get under dark skies.
You have a 10in scope; you'll be shooting fish in a bucket.
Get a nice star chart; slowly build up your sky knowledge by concentrating on one constellation and its delights at a time.
Get use to using your telrad, your right angle finder and eps.

You have a nice low power wide field ep, you also have a nice high power ep.
What you are missing is a "teener" ep. Start a cookie jar fund for a nice used premium "teener" ep.

+1!