367 replies to this topic

[KidNme]

I have a Garmin GPS and input my exact viewing site into the scope, including elevation. I'm also inputting the nuclear clock time. Once I do a 2 star align, I should be able to "GoTo" anything in the sky shouldn't I? Starry night seems to be right on target. I've seen satalites on my PC then ran outside and found them in my binocs right where and when it said it would be. I would imagine that this would translate into the "goto" of the scope and be as accurate right?

[mufoi]

Thank you for the software suggestion. I will try it out when I get my scope tomorrow and when the sky clears up.

[Hal Pollner]

Is Michael Swanson the "Mike" you are all referring to as the NexStar expert?

HAL

[spaceydee]

He is.

[nexstar8]

Nothing was mentioned about a level tripod. Is this something I'm putting time into which is not necessary.

[nexstar8]

Nothing was mentioned about leveling the tripod. Is this something I wasting my time on needlessly?

[mclewis1]

Most of us find that eyeball close is good enough for an evening of gotos. There are times when I spend a little time and use a level on my NS11 tripod ... usually when I expect to be out for more than a few hours.

Try just guessing at level for a while and see if your tracking and pointing are still reasonably accurate, if so you'll save yourself a little time each evening. If not you'll have proved to yourself the value of those few minutes you spend on leveling.

[nexstar8]

What about leveling the tripod. Is this important?

[BBishop54]

I'd level it each time if I were you. It makes it that more accurate.

[b1gred]

I have one of the $2.99 "Bullseye" round levels from Home Depot that I use to level my tripod every time I set it up. I used to level the tripod and then double check the scope base, but I've found (using the Starizona "Landing Pad") the double check isn't necessary.

I know I supposedly don't have to be that accurate to get good gotos. But, I'm an engineer and it's just the way we are...

[Clint M]

Just a quick question - not sure if this is off-topic or not, but didn't seem worth starting my own thread.

I was aligning my scope tonight, and a thought crossed my mind. I had just added an Orion 9x50 finder scope to my scope, and while there's not a lot of weight on it, it got me thinking: Would the added weight cause any problems with tracking or aligning? Would the motor/electronics "know" the extra weight was there and compensate for it?

Thanks --

[b1gred]

A little "off topic" but reasonable.

No, that amount of weight won't bother it for tracking. You don't list what kind of scope you have, if it's a GEM, just balance the scope with everything attached. If it's a fork mount, no problem, just be sure your clutches are tight. I wouldn't add much more than the finder, but it's not going to hurt you.

[Clint M]

Sorry - it's an 8SE. Thanks for the reply, Randy!

[Tel]

Hi Clint, just to add a little to what Randy said, and at the risk of stll being off topic, you can add extra weight to the 'scope without too much problem (Randy didn't know at the time what you were using).

This is my N8i which, because the OTA was originally solidly fixed to the mount arm I added a Ray's bracket so that it now clears the base. (The original design was in my view, poor but you've now got the flexibility with that dovetail fitting on the 8SE).

http://s151.photobuc...acktoNature.jpg

On top of this, therefore, it also sports a 9X50mm finder, a dew shield, as you can clearly see and a 2" diagonal plus EPs.

I think you'll find your 'scope is similarly tolerant to additional weight but just don't overdo it.

Regards,
Tel
BTW. The flowers etc. in the photo come free !

[Tel]

PS. Forgot to mention that it will also support a 6.3 or 3,3 Focal Reducer (need to shift the OTA a little more to the front with these in combination with a 2" diagonal so as to clear the base) and, as you can see from the photo, a motorised focuser.

Tel

[Jase]

Apologies if this has been asked before, but I wore the search out and did not find an answer. Since this has to do with alignment, I'm posting it here instead of creating a new thread. Hope that is alright.

I have a NexStar 5 SE and my question is with minimizing backlash. The manual states to use the final directions of the GoTo approach when centering using the example of "right" and "up". Is this universal for all 5 SEs or do "the final directions" vary from scope to scope? It also states that when the slew speed is 6 or below, "up" and "down" switch.

So when I center, I want to use the "right" and "up" buttons if I am at a slew rate greater than 6. Otherwise I use "right" and "down" buttons. Is this correct?

[Tel]

Hi Jase and welcome to CN !

You seem to be asking some questions here which need firstly to be addressed before their answers can be put together to provide you with what you seem to seek, namely good GoTOs and tracking for each object you choose to view.

Firstly though, I must point out that I am used to setting up the 8" rather than the 5" 'scopes of the SE series but in principle the same rules should apply.

Stage by stage then, let's cover the basics. I would approach things initially according to the following. However, if something doesn't work, I will need you to tell me so that I can modify the procedure.

1) Set your "GoTo Approach" to negative on the altitude axis and positive on the azimuth axis. (The altitude axis might need changing to positive if negative doesn't work but negative is the default and is normally relevant to nose heavy or neutral balance 'scopes like the 5SE. A positive azimuth axis should always be the case for northern hemisphere users).

2)Now to set up the scope's antibacklash. Firstly remember, there is no magic standard setting. All 'scopes are individual. Thus, work on one axis at a time. Point the 'scope in daylight at an object (a brick wall is good because it will give you a grid pattern).

Don't worry about high slew speeds at all (they will take care of themselves)but just concentrate on those you will need to move an object around in the eyepiece.

So, work on speeds say, 5 down to 2. Raise and lower the image of say the brick wall grid in the EP at the various slew speeds with reversals of the motion until the action is smooth on both the Alt. and Az. axes. Some delays, proportional to the chosen slew speed, will inevitably occur while the motors reverse themselves prior to making the slew but so long as these amount to say less than 10-15 secs., accept this as being of no consequence.

3) OK, now you should be ready to align. Set up your time site etc. and also make a "Calibrate GoTo". I will use the "Auto Two Star Align" for the purpose of this exercise and make the assumption you are using a red dot finder.

4) Let's assume you choose Altair as your first star. As required, you will need to manually slew to it. To get it in the sights of the RDF you will probably need initially to use the higher slew speeds which as you say are reversed from 6 upwards but you'll soon figure out which button to press to get Altair on the RDF without thinking about reversals. Let's face it, you see the star, you slew to it. If you're slewing away from it you hit the correct button !

5) OK so now you have Altair in the RDF and also somewhere in the FOV of the EP (use a 20mm or 25mm).Now you need to centralise it. Use in this case, the recommended right and up buttons in combination with a low slew speed. (Anything higher than 5 will be too fast and even at 5 you might not be able to control sufficiently. (I tend to use 4 and 3). Also centralise on a somewhat defocussed image. With the appearance of a doughnut rather than a pinpoint of light in the EP, centralisation is so much easier.

6)Once centralised in the EP hit the "Enter" followed immediately by "Align" and choose your second star, say Polaris. "Enter" and the 'scope will slew automatically this time to Polaris. Just repeat the procedure to achieve alignment success.

Now for further reference, if you go into the CN home page, select "Articles" and then "Telescope Articles" you'll see I wrote treatise on the achievement of accurate tracking in Celestron 8is 8iSEs and 8SEs which in essence, states that when you view objects which are situated premeridian, use the Right and Down buttons for final centralisation after the GoTo slew and Right and Up when postmeridian. Please read the article if you wish.

This then should iron out a few of your problems Jase. As I said, I have only worked with 8" 'scopes of this series but in principle we should, by and large, be able to read across.

My apologies if you find you know all or most of this already. On the other hand I hope it will help you to less frustrating viewing. Please feel free to ask more if necessary.

Regards,
Tel

[JDSherman]

Hi folks I was wondering if I could get some help here. I am about to try to polar align my 8iSE on a (what I believe is a) Celestron Heavy Duty wedge. I checked mike's web site at http://www.nexstarsi...lignmentFAQ.htm but I couldn't find a specific polar alignment procedure. I did find this on the web however - http://www.telescope...s/nexstar8i.pdf

The problem here is that the information from telescopereviews.com seems backwards as far as the legs of the mount go. Assuming that issue is due to the difference in the example wedge vs. my wedge, do I just point the mount arm towards celestial north (not magnetic north) and set the latitude on the wedge. After that I follow the instructions according to the controller. Does anyone have a preference on which EQ Align type is best? Also the procedure asks me to align the OTA to the meridian. Isn't it already aligned to the meridian if I start with the mount arm and the OTA pointed at the NCP?

Sorry for all of the questions. Any help is appreciated. Especially if it points out the reasons why the referenced PDF from telescopereviews.com seems backwards to me.

Thanks in advance for any help.

[MikeML]

FWIW, I don't know if all Celestron bolt patterns are the same, but I have a heavy duty wedge on a Celestar tripod. With this setup one leg points due South when aligned.
Secondly when you have your scope mounted the fork should point at the pole

[JDSherman]

Now that sounds like what I'm expecting to see. If you don't mind saying, where in NJ are you? I'm in East Windsor.

[Tel]

HI JD,

Does a Nexstar 8iSE actually fit on this heavy duty wedge ?

I was under the impression that these were only designed to carry the 8", 9.25" and 11" fork mounted 'scopes, not the single arm 6SE, 8i, 8iSE and 8SE series for which there is an appropriately designed alternative wedge available.

Regards,
Tel

[JDSherman]

I would say yes. The three bolt holes line up perfectly. The only issue I can see possibly being a problem (keep in mind I have not taken it outside yet) is that when I need to align the 90 degree OTA and arm marks the scope just touches the tray part of the wedge. I think it clears and if it doesen't I think I can finess it by moving the Ray's Bracket since it is VERY close if it indeed touches at all. Or I could just do surgery on the tray if necessary - but It looks OK by just eyeing it. I'll check it out for real if the clouds ever clear here in NJ.

[Tel]

Hi JD,

Sounds OK and with a little modification should work fine but I must admit I don't understand why, as Mike commented, one leg of the tripod should point due south. North yes, towards the region of Polaris, but south only if you're in the southern hemisphere which clearly your're not.

In normally setting up a "tripoded" 'scope for polar alignment its usual to choose one leg to be known as the "north leg" for current and future orientation of the whole set up if the viewing position is not a permanent one.

Some people therefore take to marking an "N" on the chosen leg. I always guessed that the leg of our tripods carrying the Celestron logo on it was to be used for this purpose.

(NB. the foregoing of course describes for NH users like ourselves).

If this leg is then set to point north, then the other two legs must point east and west respectively.

I don't know the heavy duty wedge that well at all but I have a standard one for my N8i (Ray's Bracket et al.)and from my experience, find Anjal C. Sharma's documented orientation perfectly sound.

I can't see therefore that the design of the wedge itself would make any difference but I may be wrong so in my case it's :

Chosen leg to the north -- mount arm to the west.

I'm puzzled therefore, but then again I may well be missing something !

Best regards,
Tel

[JDSherman]

Tel,

From what I've seen in Anjal's doc and from what Mike posted above I think for us HD wedge users the bolt pattern is reversed. There is no other way to attach the HD wedge to the standard tripod without the (a) "pointing leg" pointing south for us. No big deal. Mount arm to the west you say. That is a clue I hadn't noticed.

Thanks for your help.

[JDSherman]

I posted this in the other thread but it fits here. I found another resource for polar alignment if anyone is interested: http://c8astronomy1....tml/c8polar.htm