Veil Question

Greetings....

I recently---before the moon's light burned things out---viewed the Veil
with the 13" Coulter I bought recently. It was reasy to find and pretty
bright but not very resolved. When I've seen it in the past with my 8"
reflector, I could a lot more detail and structure. In the Coulter it
looked more like smoke. I am using a OIII filter.

Is this the optics of the Coulter or the seeing? I should have done a same
night comparison...will have to wait for that.

Regards,

Doink!

Doink wrote:
Greetings....

I recently---before the moon's light burned things out---viewed the Veil
with the 13" Coulter I bought recently. It was reasy to find and pretty
bright but not very resolved. When I've seen it in the past with my 8"
reflector, I could a lot more detail and structure. In the Coulter it
looked more like smoke. I am using a OIII filter.

Is this the optics of the Coulter or the seeing? I should have done a same
night comparison...will have to wait for that.

Regards,

Doink!



If you know the Coulter's mirror to be good, then you've likely got
collimation issues. Is the focuser square with the tube? (Use a laser
and measure the distance from the end of the tube to the laser spot,
then from tube end to laser output point).
They must agree for a normal newtonian. Then stretch a tape measure
across the inside of the tube and see if the laser hits at the halfway
mark. It should.
Once that's adjusted, use a barlowed laser. The reinforcing ring center
marker will cast a shadow around the laser output port on the return
trip. If the shadow is centered around the ring, you're there.
Try a star test before and after your precision collimation and you'll
see a big difference, I bet.
Good luck man.
Two scopes! You got the bug.
Uncle Bob

__________________________________________________ _____________________________
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"Doink" wrote in message ...

I recently---before the moon's light burned things out---viewed the Veil
with the 13" Coulter I bought recently. It was reasy to find and pretty
bright but not very resolved. When I've seen it in the past with my 8"
reflector, I could a lot more detail and structure. In the Coulter it
looked more like smoke. I am using a OIII filter.

One thing to consider is that a full-thickness 13" mirror can take
an extremely long time to reach thermal equilibrium. Indeed, on a
night when the temp is falling rapidly, it may never reach equilibrium,
especially if the tube is poorly ventilated.

This problem can be fixed with a fan.

- Tony Flanders

Thanks for the advice...
I especially appreciate Uncle Bob's collimation tips. I haven't tried using
a Barlow with the collimator.

Doink

"Tony Flanders" wrote in message
...
"Doink" wrote in message
...

I recently---before the moon's light burned things out---viewed the Veil
with the 13" Coulter I bought recently. It was reasy to find and pretty
bright but not very resolved. When I've seen it in the past with my 8"
reflector, I could a lot more detail and structure. In the Coulter it
looked more like smoke. I am using a OIII filter.

One thing to consider is that a full-thickness 13" mirror can take
an extremely long time to reach thermal equilibrium. Indeed, on a
night when the temp is falling rapidly, it may never reach equilibrium,
especially if the tube is poorly ventilated.

This problem can be fixed with a fan.

- Tony Flanders

I wish it could stop at 2! I actually have 9!!!!! (Telescopes) and I'm in
the quest of the Dream Dob!!!!!

14-15" f/6

Doink

"Uncle Bob" wrote in message
...
Doink wrote:
Greetings....

I recently---before the moon's light burned things out---viewed the Veil
with the 13" Coulter I bought recently. It was reasy to find and pretty
bright but not very resolved. When I've seen it in the past with my 8"
reflector, I could a lot more detail and structure. In the Coulter it
looked more like smoke. I am using a OIII filter.

Is this the optics of the Coulter or the seeing? I should have done a
same night comparison...will have to wait for that.

Regards,

Doink!

If you know the Coulter's mirror to be good, then you've likely got
collimation issues. Is the focuser square with the tube? (Use a laser and
measure the distance from the end of the tube to the laser spot, then from
tube end to laser output point).
They must agree for a normal newtonian. Then stretch a tape measure across
the inside of the tube and see if the laser hits at the halfway mark. It
should.
Once that's adjusted, use a barlowed laser. The reinforcing ring center
marker will cast a shadow around the laser output port on the return trip.
If the shadow is centered around the ring, you're there.
Try a star test before and after your precision collimation and you'll see
a big difference, I bet.
Good luck man.
Two scopes! You got the bug.
Uncle Bob

__________________________________________________ _____________________________
Posted Via Uncensored-News.Com - Accounts Starting At $6.95 -
http://www.uncensored-news.com
The Worlds Uncensored News Source