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#1 csa/montana

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Posted 02 May 2006 - 12:34 PM

Thru the kindness of a fellow CN'r who made the degree circles for me, I now have the complete setup for $12. I had the degree circles laminated on both sides (Staples-$2)
Bought an inclinometer (Home Depot $10). Had an old wall clock that I removed the hands from for pointers.
The Altitude Degree was affixed with dbl-stick tape. I siliconed the clock hand between 2 thin washers, & installed it first, against the scope, on the "spring" bolt.
Then, with the inclinometer, I adjusted the clock-hand pointer, until they agreed, all thru the scale.
On the base, again I used dbl-stick tape to affix degree circle. I drilled a small hole in the side of the lower base, using a stainless steel screw, mounted the other clock hand (hour). I then bent it to clear edge of other base & forward to point to scale. I think the set-up looks great; I don't need the inclinometer now that the pointer has been coordinated. Of course, now a front has moved in with total overcast, so I cannot try out the new "Go-To" $12 system!
Carol

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#2 csa/montana

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Posted 02 May 2006 - 12:58 PM

Another

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#3 csa/montana

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Posted 02 May 2006 - 12:59 PM

Last picture.

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#4 rnabholz

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Posted 02 May 2006 - 01:12 PM

Carol,

Looks great, nice job.

Regarding the inclinometer versus altitude scale. The advantage of the inclinometer is that it reads the true angle of the tube regardless of the angle of the base. A base that is even just sightly off from perfect level can introduce errors into your altitude readings, and at least in my case, my eyepiece's widest field at just 1 degree leaves me little room for level induced errors.

You can certainly keep the scale, but I would take great care in leveling the base, and if it were me, I would leave the inclinometer in place during observing as a way to confirm the scale's readings.

Good Luck with the system, I'm cheering for you.

#5 csa/montana

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Posted 02 May 2006 - 01:19 PM

Rod: Thanks for bringing that to my attention! I will definitely use the inclinometer. Soon I am getting the digital one you have, I have the base all ready for it.
Also thanks for all your help & encouragement, so I can have a "Go-To" scope!
Carol

#6 dgs©

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Posted 02 May 2006 - 01:25 PM

Looks real snazzy... kind of like the scope should have come with them as original equipment. :whistle:
The clock hands are a good idea. :waytogo:

Make sure your base is very level whenever you set it up, otherwise your Alt scale could be off a little.
I assume you are using a compass to align your Azimuth scale with true North? If so, keep in mind that magnetic North and True (celestial) North don't always agree. Furthermore, magnetic North wanders around, noticeably over the course of a few years.
Here is a good NOAA site for determining what your magnetic declination is.

#7 SkyArcher

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Posted 02 May 2006 - 01:35 PM

Carol, That looks great! You did a nice job!

#8 csa/montana

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Posted 02 May 2006 - 01:37 PM

Thanks to "Honey's" master!

#9 csa/montana

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Posted 02 May 2006 - 01:44 PM

Thanks David: It was suggested to me that I point the scope to Polaris, then rotate base to "0". I will try both this, & a compass if & when the "curse" lifts the clouds, :bawling: to see which is easier for me & most accurate.
Carol

#10 Hillbilly_Gazer

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Posted 02 May 2006 - 01:51 PM

Looks real snazzy... kind of like the scope should have come with them as original equipment.


That was my exact thought. Nice work!

#11 typhus

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Posted 02 May 2006 - 03:00 PM

Those are nice Carol. Using the degree circles sounds like it would be more fun observe than DSC. Let us know how they work out for you.

#12 Curt B

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Posted 02 May 2006 - 11:46 PM

Good luck Carol. When I did the same thing to my dob, it opened up a whole new world for me! What program are you using to find the objects?? I use Planetarium on my Palm. I also play around with PleiadAtlas. It is an easier interface than Planetarium, but I don't think it is quite as accurate, but still gets you pretty close.

#13 csa/montana

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Posted 03 May 2006 - 08:55 AM

I haven't decided on a program yet; do you have a website for PleiadAtlas? The easier, the better for me! Also, did you use a compass on the base, or put scope on Polaris, & turn the base to "0"?
Thanks!
Carol

#14 rnabholz

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Posted 03 May 2006 - 10:36 AM

Carol,

When you get tired of hearing from me, just say so.

With regards to aligning the base, I have a cheap $4 compass permanently installed in the base of my scope that helps me get somewhat close to north when I set up the scope.

Then, to "calibrate" I use any known object, many times a star or planet visible well before Polaris is visible. Center that object in the field and adjust the dial to match. My approach was to build it about 20 degrees of adjustability on the dial. That approach allows you to adjust without disturbing the position of the scope, nice if you have spent any time carefully leveling the base.

Remember that each time you move the scope base to adjust your calibration, you will likely move the scope enough to loose the calibration object and will have to reacquire the target and check the reading and repeat. Might be a bit tedious.

An approach I have seen in a set up like yours with a non-adustable scale is to make the pointer movable. One way to do that is a pointer mounted on a magnet that attaches to a steel plate along the edge of the scale. Once centered on an object, You simply move the pointer to match the appropriate reading, again leaving your scope undisturbed, still level and centered on your calibration target.

Hope this helps.

Rod

#15 csa/montana

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Posted 03 May 2006 - 10:56 AM

Rod: I won't live long enough to get tired of you trying to help me get set up! Can you explain a little more about the steel plate along the edge of the scale? This idea sounds great, as I know it will be very difficut for me to move the base (full weight of scope!).
Carol

#16 rnabholz

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Posted 03 May 2006 - 11:19 AM

Carol,

Imagine a piece of thin steel - the steel strapping used on lumber or pallets would work great. You simply attach, say, 6 inches of that to the edge of your groundboard with a couple of screws.

Then attach your pointer to a small magnet, and stick it to the center of the steel strip.

When you need to tweak your calibration you simply slide the pointer along this strip of steel strapping until it matches the computer's azimuth setting and you are good to go.

Let me know if that is clear as mud and I will try again. :p

Rod

#17 csa/montana

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Posted 03 May 2006 - 11:52 AM

Rod: something else that may work is magnetic stripping. I called the local hdwre store, & they have it (used for holding screwdrivers, etc.) It's flexible, so I thought I'd screw it around the edge of the base, then mount my clock-hand pointer on a small magnet. What do you think of this?
:question:
Carol

#18 rnabholz

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Posted 03 May 2006 - 12:06 PM

My only thought on that might be that you could have a situation where the polarities of the strip and small magnet would clash and not let you place the pointer precisely where you would like. Take the small magnet to the store and try it out.

If you live anywhere near a lumberyard or home improvement center, they would likely let you take all the steel strapping you wanted for nothing. Most of the time the yard is littered with the stuff and some poor soul (like me on my summer job as a kid) has to schlep around and pick it up and toss it.

#19 csa/montana

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Posted 03 May 2006 - 12:26 PM

After thinking about it, I agree, the strapping would be better (and the price? PRICELESS!) Besides, the cost will still be $12, + 1 small magnet, & a few s.steel screws! How much better can it get? Off to the lumber yard, I go!
Now, all that will be left? Overcast, go away! :cloudy:
Carol

#20 SkyArcher

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Posted 03 May 2006 - 01:40 PM

Carol, I use Pocket Stars on my PDA (Dell Axim) and Cartes du Ciel on my laptop to give me the coordinates that I need to find stuff. CdC is free but Pocket Stars is $19. CdC shows the comets and lets you update the database. Pocket Stars does not show comets but if I look up the comets on CdC then I can pick it out from the Pocket Stars.

The PDA is definately easier to use out in the field than the laptop.

#21 Fireball

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Posted 03 May 2006 - 04:21 PM

Carol,

Imagine a piece of thin steel - the steel strapping used on lumber or pallets would work great. You simply attach, say, 6 inches of that to the edge of your groundboard with a couple of screws.

Then attach your pointer to a small magnet, and stick it to the center of the steel strip.

When you need to tweak your calibration you simply slide the pointer along this strip of steel strapping until it matches the computer's azimuth setting and you are good to go.

Let me know if that is clear as mud and I will try again. :p

Rod


Sounds interesting and simple.
Is it possible to show a picture of this set-up ?
That would make everything very clear.
Thanks !

#22 csa/montana

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Posted 03 May 2006 - 04:37 PM

Fireball: Go to top of this post, my first picture.
On the outer side edge of the lower circular base, the metal strip will be affixed there, completely around the base; then where the pointer is,(screwed in), I now will have the pointer glued to a small magnet that I can now move anywhere on the degree circle, to get set up.
Carol

#23 csa/montana

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Posted 03 May 2006 - 04:43 PM

Ron: Just downloaded trial PC version, & am ordering PC & PDA version. This is a great program, just what I was looking for. Now, I'm going to try to find a good price on the Axim. Again, thanks for all your help, couldn't have done it without your kindness & expertise!
Carol

#24 Curt B

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Posted 03 May 2006 - 05:52 PM

Here is the link for Pleiadatlas

http://astro.isi.edu/pleiadatlas/

and Planetarium

http://www.aho.ch/pilotplanets/

#25 rnabholz

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Posted 03 May 2006 - 08:59 PM

Carol,

Of course the call is yours to make, but if it were me, I wouldn't bother to make the strip go all the way around.

6-12" of strapping would give you around 30 to 45 degrees of adjustment, plenty for even a casual initial polar alignment.

Just another two cents - making my total to date $3.08.............Sorry.






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