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CG-5 slewing arrows - Need Help!!!!

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#1 James Cunningham

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Posted 21 April 2011 - 10:38 PM

I have a alt/az for my 11 inch scope and have no problem slewing because the direction arrow move the mount in the direction of the arrows. I have had my 150mm refractor on the CG-5 mount and cannot get the hang of where the mount is headed when I push the arrow keys. Any suggestions on how to determine which direction the mount is going to go when pushing the direction keys? Also, I am not sure that my mount is level. The tiny level bubble is hard to read. Is there anyplace where I can place a larger level bubble to make it easier. Tonight was the first time I tried the mount my self. Total failure! I got Polaris in the Polar scope, think I had the scope level and then pressed the button to slew to the first alignment star. There were several stars visible so I picked the brightest one for alignment. Then pushed the button for the next alignment star. Again, several stars were visible but none of them stood out. I picked one. To make a long story short, Although the had set said I had an alignment, I did not. It could not find Saturn and I looked all over the place for it. HELP!!

#2 jrcrilly

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Posted 21 April 2011 - 10:52 PM

The up/down buttons slew you toward or away from Polaris (up = toward). The left and right buttons slew in a circle around Polaris (right = counterclockwise).

To check your star alignment, it's best to use only stars or deep space objects. You could have a perfect alignment but if time/time zone/date/location info is wrong it still won't find planets. May as well eliminate those variables first. If it finds stars, then check planets as a means of checking your setup data.

#3 James Cunningham

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Posted 21 April 2011 - 10:59 PM

Thank you. I will try that. So, if I am facing west, and I push the up arrow, it will slew left toward Polaris?

#4 rmollise

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Posted 22 April 2011 - 05:57 AM

Thank you. I will try that. So, if I am facing west, and I push the up arrow, it will slew left toward Polaris?


You need to put up/down/left/right away and just think north-south-east-west. You'll find that will help a lot not just in figuring out which way the buttons go, but in observing in general.

#5 James Cunningham

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Posted 22 April 2011 - 06:08 AM

So, if I am facing west and I want to go left (west). Which button would you push?

#6 jmiele

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Posted 22 April 2011 - 10:16 AM

So, if I am facing west and I want to go left (west). Which button would you push?


Push the one that makes it go west :)

Forget which button that is. Once your in the EP, things will change again. N-S-E-W may or may no be top-bottom-left-right depending on Diag being present where and how the scope is pointed. You got a goto scope so the mount could worry about it :) At some point my brain adjusted (took longer for me :) ) and now I push the buttons correctly. But thats only for when I'm at the EP making small adjustments.

FWIW... Joe

#7 rmollise

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Posted 22 April 2011 - 05:02 PM

So, if I am facing west and I want to go left (west). Which button would you push?


Uhhh...the west button? As in the left of the two horizontal arrow keys.

#8 rmollise

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Posted 22 April 2011 - 05:04 PM

Push the one that makes it go west :)

Forget which button that is. Once your in the EP, things will change again. N-S-E-W may or may no be top-bottom-left-right depending on Diag being present where and how the scope is pointed.


directions will be different in the diagonal, but pushing the "west" button will still move things west.

#9 James Cunningham

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Posted 22 April 2011 - 05:05 PM

When you say the "west" button, do you mean the button which is on the left?

#10 jrcrilly

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Posted 22 April 2011 - 05:14 PM

I think this thread is encouraging confusion between compass directions on the ground and celestial directions. The buttons on the handbox move the mount in specific directions relative to the sky, not to the ground. As I point out above, the declination motor (North and South buttons) moves the telescope toward or away from Polaris (he mentioned having Polaris in his PAS, so we know we are dealing with the Northern hemisphere). Those are the only two directions it can go. That could be ANY compass direction, depending on the area of sky involved. RA moves the mount in a circle centered on Polaris and it can only go clockwise or counterclockwise (East and West buttons). That's all it can do. Again, that can be any ground-based direction.

#11 Trev

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Posted 22 April 2011 - 05:19 PM

When polar aligned you can think of the RA axis as East and West, Dec as North and South.
That probably won't help much...

#12 James Cunningham

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Posted 22 April 2011 - 05:23 PM

So the RA is controlled by the arrows pointing up and down and the Dec is controlled by the arrows pointing side to side? Have I got that right?

#13 jrcrilly

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Posted 22 April 2011 - 05:32 PM

So the RA is controlled by the arrows pointing up and down and the Dec is controlled by the arrows pointing side to side? Have I got that right?


Other way.

#14 James Cunningham

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Posted 22 April 2011 - 05:33 PM

Thanks for correcting me.

#15 Trev

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Posted 22 April 2011 - 05:40 PM

When your set up check the directions and just make up a small chart to remind you until your used to using it.

#16 James Cunningham

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Posted 22 April 2011 - 05:43 PM

Before I start writing down which direction the arrows move the scope, should I point the scope toward North?

#17 Trev

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Posted 22 April 2011 - 06:00 PM

No your just checking to see which way the mount moves when you push the buttons.

Once you get the hang of not thinking in left/ right you'll wonder why you had trouble with it.

#18 SkipW

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Posted 22 April 2011 - 08:11 PM

The up/down buttons slew you toward or away from Polaris (up = toward). The left and right buttons slew in a circle around Polaris (right = counterclockwise).

I hate to add to the confusion here, but the "up = toward [Polaris]" isn't correct. Sometimes it's the opposite (see below). When looking straight down the Dec axis from above (i.e. from the OTA side, toward the counterweight), Up causes the Dec axis to turn counterclockwise and Down causes the Dec axis to turn clockwise. If the telescope is pointing east (and not "turned over" underneath the mount), pressing the Up button does indeed move the telescope toward Polaris. If you keep moving in that direction, however, eventually you will pass the NCP (North Celestial Pole) and continue turning in the same physical direction away from the NCP (and Polaris). Keep going long enough, and you'll eventually pass by the SCP, which you can't see through the dirt but is actually there, and resume turning toward Polaris - and completely wrap the Dec Motor cable, but we'll ignore that.

The rest is correct. In the Northern Hemisphere, anyway, the Right arrow moves the polar axis counterclockwise (when looking up through the "tail" end of the mount toward Polaris), increasing Right Ascension (westward).

This behavior can be reversed with menu selections, but I've never tried it. I don't know if the left-right (or up-down) behavior is reversed in Polar-South mode or not. I've never tried that either.

Did you know that you can get the mount to slew at maximum rate by first pressing a button in the direction you want to go, then pressing the opposite button? I'd suggest just trying each button at maximum rate and looking at what the mount does.

#19 James Cunningham

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Posted 22 April 2011 - 08:18 PM

OK, now I am confused. Only thing for me to do is go out to the garage tomorrow and just hit all four arrow keys to see which way they go and make notes and keep those notes handy until I get the hang of it. Thanks to all for first clarifying everything and then confusing me all over again.

#20 Trev

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Posted 22 April 2011 - 10:24 PM

That's what we're here for Jim, glad we could do a good job. ;)

#21 SkipW

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Posted 22 April 2011 - 10:24 PM

Again, sorry for the confusion. Just remember, pressing the up and down arrows rotate the scope north and south (not necessarily up and down), and the left and right arrows move it in decreasing and increasing RA. Best is just to try it and see. The highest-speed slewing makes it possible to see what is actually happening.

#22 solshaker

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Posted 22 April 2011 - 10:28 PM

Thanks to all for first clarifying everything and then confusing me all over again.


:lol: .sorry man, but thats funny.

dont sweat wrapping your head around the eq mount. it will take a few sessions to get an intuitive feel moving it about. thats a great idea to set up in the garage with the scope pointing north and just loosen the clutches and practice pointing at where saturn and other bright objects would be. better yet, do it outside and use saturn, the moon and stars like sirius and arcturus to practice moving the mount around (be sure to properly balance the mount and the scope should move smoothly and not get away from you). sighting down the tube and using a finder helps.

when you (finally) get an object in the ep, lock the clutches and let the mount track and fool with the buttons and youll soon figure out the directions. after a while youll get the hang of it and the celestial sphere will make sense in relation to the mount.

it took me quite a few sessions to get efficient and "accurate". once you get it down, its easy.

#23 James Cunningham

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Posted 23 April 2011 - 06:11 AM

You say "when you (finally) get an object in the ep, lock the clutches and let the mount track"
I had no idea that if I get something within the eyepiece by slewing with the buttons that it would track whatever is in the eyepiece. How will the mount know to track that object?

#24 rmollise

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Posted 23 April 2011 - 07:44 AM

So the RA is controlled by the arrows pointing up and down and the Dec is controlled by the arrows pointing side to side? Have I got that right?


Nope...you are still Bassackwards. :lol:

#25 James Cunningham

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Posted 23 April 2011 - 07:48 AM

Yeah, someone corrected me earlier in a post. Thanks.






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