Nexstar help

[jim d]

Have 3 questions about Nexstar SE6.After alignment when you slew to an object does the scope than track and stay with object?Mine will apparently stay with a star but it did not stay with Jupiter.

When looking at a star it looks like two rings of light with a dark center is that then in focus? which leads into third question if two people have completely different vision when focused on object do you then fine tune.I am completely new at all this as you can tell.

[jim d]

One more question.

After correctly aligning scope and slewing to an object does scope then keep tracking that object.When I go to Jupiter it does not track.Jupiter moves right across fairly quickly.But stars stay tracking.When I got to jupiter I used the hand controller to center a little better, but Jupiter moves out of field of vision fairly quickly,does that make a difference?

[rowan46]

you will enjoy your scope after a while but as you say there is a bit of a learning curve.

Q 2 focus if your stars are showing dark rings round them you're not quite in focus.

Q1 once the scope has been aligned it will track your targets, with some exceptions.

Q3 it will not track a planet or moon or sun unless you first go to it this is because they do not move across the sky in the same way as the stars. so to answer the question tell the mount to go to the planet , then it will track. Nb before anyone tells me about the stars moving across the sky. I know its the earths movement not the sky just didnt want to complicate things

[rowan46]

sorry forgot to answer the other focus question people focus according to their own eyesight so it's quite normal to be refocussing a scope when sharing, if they have different eyesight

[Nexus 6]

Hi jim,

Have you adjusted the rate button when you have, for instance, the Moon in the eyepiece. If you go to List on the handset and select Solar System when you pick any object that is available to slew to, ie Jupiter, once it is in the fov the scope will track it. Depending what power ep you are using will determine how fast you should set the slew rate.

Alan

[jim d]

Alan,

Thanks for info,one question though.Using Jupiter as an example after slewing to Jupiter and it is in fov should I then slow the slew rate or should I slow the rate before going to Jupiter.Iwould try this out but weather in my area has been cold and rainy. Jim

[Demonperformer]

My understanding is that you should use sideral rate unless viewing the moon (Lunar rate) or the Sun (solar rate)

[Nexus 6]

DP, your right of course, regarding setting Sidereal, Lunar or Sun depending on the object in question.

Jim, for your scope to track any solar system object you will have to do a 2 or 3 star alignment first. After that you can then use the List option on the handset to select Solar system and then the scope, once slewed, should hold it in the fov by tracking at the correct rate. The rate is dependant on what power eyepiece you are using, high power 7,8,9. Low power 4,5,6. You should have the rate set to 6 when you begin your 2/3 star alignment. Hope that helps.

Alan

[Capricorn]

Think that you will just have to accept that planets move slowly out of the field of view.

The stars all "rotate" at a fixed rate. However the planets rotate because of the earths rotation and because of their own orbital velocity.

As each planet has their own orbital rate then all planets appear to move at a different rate. So I would suspect there is no planetry rate. Also Mars moves in one direction, then slows and moves backward, slows again and starts to move the normal direction again. so at one date it may be moving L->R at another R->L. The limited computing power of a goto simply cannot handle everything.

Just recentre Jupiter before it moves too far, thats what the handset is for after all.

[brantuk]

Once you've worked out the tracking rate (using the good advice above) you should find it will track Jupiter for a good 2-3 hours before even going just slightly off center. But you'll be on other objects long before that lol

[Nexus 6]

Capricorn, agreed there is no planetry rate. I normally do have to tweak the object back into the fov to carry on with my observing. I think, if my experience is anything to go by, for a beginner Go -TO can sometimes be a bit of a pain. In reality it took me 6 months to get to grips with my old 6se. Had only just become aware of Stargazers Lounge and had not really used it that much. That was a mistake! I may have got to the bottom of things a bit sooner.

Alan

[Ags]

Nexus6 says: "the scope, once slewed, should hold it in the fov by tracking at the correct rate. The rate is dependant on what power eyepiece you are using, high power 7,8,9. Low power 4,5,6."

Erm, the tracking rate would definitely not be related to current magnification. Regardless of mag, the object is still moving across the sky at the same speed (higher magnification just makes it look faster) so the telescope tube would have to slew at the same rate regardless of the magnification.

If the scope can figure out where the planet is in the sky, then by implication it can track it. My experience of the NexStar is that, backlash issues aside, it keeps a planet in 0.3 degree FOV for 20-30 minutes when it is aligned well.

[Nexus 6]

Thats a fair point Ags. I thought I would try and keep the point or the question easy for Jim to understand. Simple to follow but not entirely correct.

Alan

[rowan46]

have just re read my post and I have to admit I was talking b*** I ve had too many late nights recently. If your scope will find it it should track it . Its only the moon and sun that needs the rate changed. my apologies I must stop posting at 4 in the morning

[jim d]

Still not sure what correct answer is,some of you say it will only be in fov for a short while and then you have to use hand controller and re center,others that once it is fov then will track and stay there for hours.I am confused:icon_scratch: Also I an using a 25 mm eye piece not sure what the 7,8,9 is.was told when scope was bought it will stay on and track objects.Celestron says same thing.Either or I dont care just want to know

[Helen]

If you properly set up and carefully align the scope (using 3 star align is best), do a goto and centre the object carefully again, then it will keep the object in the field of view for quite a long time (exactly how long will depend on your alignment accuracy, and perhaps balance).

I really like using my Nexstar because its easy to set up and tracks well.

Helen

[cgarry]

Still not sure what correct answer is,some of you say it will only be in fov for a short while and then you have to use hand controller and re center,others that once it is fov then will track and stay there for hours.I am confused:icon_scratch: Also I an using a 25 mm eye piece not sure what the 7,8,9 is.was told when scope was bought it will stay on and track objects.Celestron says same thing.Either or I dont care just want to know

Once aligned if you goto an object it should stay in a 25mm eye piece for hours. You do not need to worry about setting rates or anything else it will just track the object you have selected.

The only time I have found an object drift out of view is if the initial setup was not done properly (tripod not completely level, alignment stars not centred accurately or time/location not accurate).

As has already been said, ignore all that stuff about 7,8,9 - that makes no sense whatsoever.

Chris

[Ags]

The only time I have found an object drift out of view is if the initial setup was not done properly (tripod not completely level, alignment stars not centred accurately or time/location not accurate).

Chris

The other way an object can drift out once you have GOTOed to it, is because of backlash. This occurs if the goto is not 100% accurate and you have to correct the scope with the handset. If the scope has to reverse direction from your last slew in order to track the object, there is a slight delay before the gears kick in, causing the object to drift to the edge of view. Backlash (and how to avoid it) is explained in the NexStar manual, probably better than I have done.

[cgarry]

The other way an object can drift out once you have GOTOed to it, is because of backlash. This occurs if the goto is not 100% accurate and you have to correct the scope with the handset. If the scope has to reverse direction from your last slew in order to track the object, there is a slight delay before the gears kick in, causing the object to drift to the edge of view. Backlash (and how to avoid it) is explained in the NexStar manual, probably better than I have done.

Agreed, backlash can be an issue. However, with a 25mm eyepiece the object would have to drift a long way to get out of view.

[rowan46]

this site is useful http://www.nexstarsite.com/

[Nexus 6]

Seems some the help given in this thread has only managed to confuse the poster!

Jim, apologies for my part in that.

Alan:o