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Nexstar 8SE clock question

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#1 BuckW

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Posted 26 November 2012 - 06:01 PM

Hello all,
I am new to this so be gentle :help:
I have not been able to get a successful align yet and I think the problem is the clock setting. I set the clock initially and thought that was it but it appears the clock is not running when the scope is powered off ( I figured it would be like a laptop but maybe not so ). I did a custom site with our backyard lat/Lon per GPS and it saved all the settings but, later, the clock is still at the initial setting. I thought it was because I had no batteries in the base so I installed 8AA's but same thing seems to be the case.

One more quick question to display my ignorance - when I go to "View Time-Site" there is one line listed as LST and a time - initially I thought this was the Zulu time but it does not seem to fit - so .... ???

Thanks so much for your time.

#2 Tel

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Posted 26 November 2012 - 06:14 PM

Hi BuckW,

Firstly a very warm welcome to CN and to this forum ! :bow: :bow:

Quite simply, time entries are not retained by this 'scope.

In other words, you have to input your local time, related to your Time Zone, (the latter which incidentally the 'scope will retain), each time you set it up for an observing session.

Onto your second question, I would assume LST means Local Standard Time.

Hoping this helps,

Best regards,
Tel

#3 BuckW

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Posted 26 November 2012 - 06:27 PM

Thank you Tel --
I believe you have verified the conclusion I was slowly coming to - no real timeclock. I guess in this day and age I just assumed -

On the LST - the delta between what I set as local and the LST reading is like 4 to 5 hours - I'm sure there is a operator error going on here.

Anyhow, Thanks a lot for your response and time.

#4 Tel

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Posted 26 November 2012 - 06:42 PM

Sorry, BuckW: Wrong assumption ! I had to go to my manual to look up Celestron's definition of LST. It relates to Local Sidereal Time and is described as follows,

"LST is useful for knowing the Right Ascension of celestial objects which are located on the meridian at that time".

It's a feature I've never ever used !

Best regards,
Tel

#5 Midnight Dan

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Posted 26 November 2012 - 07:32 PM

no real timeclock.


In the normal sense of a realtime clock, you're correct. The clock does not keep ticking and remember what time it is between startups. But ... the clock DOES keep ticking during a session so it knows where things are at different times during the night.

But the only thing it remembers between startups is the time you set at the last startup. So at least it remembers the daylight savings time setting. And if you find you have to restart during the night for some reason, you won't have to set the date again - assuming you haven't transitioned through midnight.

-Dan

#6 Peter9

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Posted 27 November 2012 - 04:23 AM

Hi BuckW and welcome to the Nexstar forum.

Good to see you have at least got started with your 8se.

You've come to the right place to sort out any problems, like the one above, you may encounter.

Good luck and enjoy.

Regards. Peter.

#7 BuckW

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Posted 27 November 2012 - 10:33 AM

Thanks so much for your comments gentlefolks - as I understand it then - the computer retains certain parameters in memory ( Static RAM ?? ) unpowered but no clocking. So, at each setup/session I need to enter local time/date and any deltas to location - got it!!

Follow on question - I assume the GPS option would negate this need then ( I am old and have but one functional brain cell and it is limping so less to remember is better ). In looking around I find that CN16 is Celestron's option but I see two different part numbers - 93963 and 93968 - would either work?

#8 Midnight Dan

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Posted 27 November 2012 - 10:51 AM

Hi Buck:

Correct. The GPS will enter the time/date/location for you. But unless you take your scope long distances frequently, it seems like a lot to pay for that convenience since it really is only entering the time/date for you. Are you sure your single brain cell can't handle that? Mine seems to be able to! :grin:

-Dan

#9 BuckW

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Posted 27 November 2012 - 11:19 AM

:) Hi Dan,

Yeah, I probably will not go that route just yet - just seem to have a need to understand the problem and, hopefully, remember the solutions.

Can not tell you all how much your help is appreciated - I read the manuals and any related books I can find but answers just seem to allude me. I found forms like this populated by giving and understanding folks to be invaluable.

#10 Tel

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Posted 27 November 2012 - 12:07 PM

Hi BuckW,

If you haven't done so already, you may find that the thread above on this forum's main page window entitled "Links annd Best of the Celestron Nexstar Forum" is worth a visit, particularly the section subtitled "Useful Forum Threads" although I'm sure you'll find the others the others very helpful.

In full agreement with that Dan has already advised; certainly don't waste any money on GPS units. They are of very limited use and do nothing that you cannot do for yourself, once the simple task of entering time and date has been carried out a few times.

But should you feel it necessary to reco-ordinate the 'scope if you move it to a distant location, bear it firstly in mind that your existing co-ordinates will still serve at least within a 70 mile radius of your current "homebase". On the other hand, should you have to change them as a result of moving even further afield, then new, latitude/longitude co-ordinates are of course readily accessible and free of charge from the likes of "Google Earth" etc. !

Best regards,
Tel

#11 Skip

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Posted 27 November 2012 - 06:51 PM

Hi BuckW,

Welcome to our little corner of the CN universe!

Good advice from the guys here (as always!). If I am going to go somewhere more than 60 or 70 miles from home, I do exactly as Tel (hmpf - probably learned it from him!). I look up the new location on Google Earth, jot down the lat/long, and hit the road with my scope.

Have fun and hang here often. And again, welcome!

#12 Bob Griffiths

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Posted 27 November 2012 - 07:27 PM

I DO have a CN-16 GPS mounted on my 8i... I traveled with the scope during the work week the last 2 years before I retired and often set up hundreds of miles away from the place I set up the night before.. so entering the correct location was mad easy...in addition to that the 8i originally did not have Skyalign and you had to also point the scope North to begin your alignment and then level the OTA..(the GPS did both of these two things also....

Today I would not even think of buying a GS unit..total waste of good money... In fact I also have a CPC1100 which comes with a GPS ..IF that GPS suddenly died .I would not even consider fixing it...

BTW.. I run ALL my scopes on standard time year round.. never bother with Daylight Savings time..
I'm darn good at math and when the scope GPS tells me it 9 PM in the summer and my watch says its 10 Pm I can do the math and accept the GPS time... If I am using one of my scopes without a GPS I just enter the time one hour earlier then what my watch says in the summer...

Ad Dan noted these scope do keep elapsed time starting when you hit align on your first alignment star.. If you do not move the scope you can put it in hibernation (power it off) but when you wake it up you then have to enter the correct time and date again..

Bob G.

#13 BuckW

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Posted 29 November 2012 - 08:00 AM

Well gentlefolks - it all went exactly as you said!! Once I set up properly "GoTo" did just that and tracking held great! Saw Jupiter (somewhat washed out due to the full moon right next door ) and three moons - while we watched out popped a fourth!!! ( IO? ) Fantastic! Wife is now a convert - big plus! ( talking about better eyepieces and taking pictures - I see there is fun in the future ;-) )

One thing I noticed was a shift in the view as I focused - ran to the books and that seems normal for this design scope - but this is for another thread.


Once again - Thanks to you all!!!

#14 Midnight Dan

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Posted 29 November 2012 - 09:49 AM

Another happy customer! We can all now submit our forms to Celestron for kickbacks. :lol:

-Dan

#15 Arctic_Eddie

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Posted 29 November 2012 - 09:51 AM

Image shift is common as the focus mechanism is a push/pull device that is connected to only one side of the mirror. One thing that helps slightly is to make your final focus action in the CCW direction of the knob. This will push the mirror up the baffle tube against gravity and remove any mechanical slack in the system.

Running the focus carefully through it's full range(about 30 turns) a few times will help distribute the grease evenly and help the situation. You might do this about once a year.






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