GOTO in Theory and Practice

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Tetenterre
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GOTO in Theory and Practice

Post by Tetenterre »

Inspired by a post in another thread:


Theory:
1. Select object from menu
2. Press ENTER
3. Press GOTO
4. Observe requested object

Practice:
1. Initialise mount with n-star alignment.
2. Select object from menu
3. Press ENTER
4. Press GOTO
5. Wait while the mount slowly drags the scope to somewhere near your target object.
6. Fiddle with slo-mo controls to get object centred.
7. Realise that it looks nothing like what it should and start again.
8. Start again and get exactly the same result as the first time.
9. Realise your knowledge of bright stars is depleted by your reliance on GOTO and has caused you to align on Castor instead of Pollux; start again.
10. As the mount stops mid-slew, realise that you forgot to put fresh batteries in the handset.
11. Fortunately, you have a battery pack. Plug that in and start again.
12. As the mount stops mid-slew, realise that you forgot to recharge the battery pack.
13. Go indoors and remove batteries from remote controls, radios and anything else that has the same size batteries as your handset.
14. Start again.
15. Eventually get the correct object centred.
16. Your success has caused you to get blasé, so you select M86 (+ repeat 4 & 5)
17. Mount puts you exactly in a blank space surrounded by several galaxies.
18. Realise your knowledge of visual fields is depleted by your reliance on GOTO and you haven't a clue which galaxy is which.
19. Go indoors to get star chart.
20. Even though you didn't put any lights on, you realise that your dark adaptation must have been damaged because you can no longer see the galaxies that surrounded your blank bit of sky.
21. As you gaze into the eyepiece waiting for your dark adaptation to return, a point of light drifts across your field of view. Slow-moving satellite?
22. As more points of light drift across the FoV, you realise that it is strangely silent: your mount has stopped tracking.
23. You realise that the cold has caused your batteries to drain quickly. Your mount is now entirely useless.
24. In great disappointment because it's such a fantastically clear (if cold) night, pack kit away and go to bed (again forgetting put your battery pack on charge).

Next Clear Night:
25. Still powerless. Nothing works. Put battery pack on charge.

Next Clear Night:
26. Spend 30 minutes carefully getting mount perfectly aligned, only for the clouds to roll in before you've had a chance to observe anything.

Next Clear Night:
27. Initialise mount with n-star alignment.
28. Select object from menu
29. Press ENTER
30. Press GOTO
31. Wait while the mount slowly drags the scope to somewhere near your target object.
32. Fiddle with slo-mo controls to get object centred.
33. Realise that it looks nothing like what it should and start again, this time selecting M42, because you remember where that is and know how to find it.
34. Wait while the mount slowly drags the scope to nowhere near your target object -- it is pointing vaguely north.
35. Realise that the reason it goes to apparently random wrong bits of sky is that you'd inadvertently switched it to 'southern hemisphere' mode.
36. Switch to 'northern hemisphere' mode and start again.
37. Wait while the mount slowly drags the scope to nowhere near your target object -- it is pointing at Virgo.
38. Realign mount and try again, this time selecting the Pleiades.
40. Wait while the mount slowly drags the scope to nowhere near your target object -- it is pointing just north of Leo.
41. Read the "Common Problems" page in the GOTO handbook; your problem is not described.
42. Search for the problem on Google.
43. An hour and a half later, you discover a similar problem when someone set the handset to the wrong timezone.
44. Realise that the previous battery-free time has caused the handset to default to Pacific Daylight Time.
45. Go outside, start again, selecting M42.
46. Handset reports "Object below Horizon".
47. Realise that everything on your observing list for the night has set; it's 2.30am and you have to get up for work in 4 1/2 hours.
48. Pack up your kit and go to bed (actually remembering to put battery pack on charge this time!)

Next Clear Night:
49. Use binoculars and the unopened copy of Turn Left at Orion that your in-laws thoughtlessly gave you just after you'd got the GOTO telescope.
50. You have become a contented astronomer!
Last edited by Tetenterre on Sun Jan 13, 2013 3:21 am, edited 1 time in total.
Best,
Steve
The Binocular Sky
Astronomers do it with Heavenly Bodies

Lots of binoculars, from 32mm to 100mm; 90mm Gregory-Maksutov, 406mm Dob
David Frydman
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Re: GOTO in Theory and Practice

Post by David Frydman »

I enjoyed that.

What about trying to use a GO TO from indoors through the window, that should be fun.

regards, David

I think the solution is to stop the Earth and the solar system turning in any direction, make the Earth flat, and start from there.
joe
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Re: GOTO in Theory and Practice

Post by joe »

51. Once all binocular objects are observed, begin drooling over 300mm newtonians/100mm apos in AN/S&T/S@N magazines.
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
Guy Fennimore
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Re: GOTO in Theory and Practice

Post by Guy Fennimore »

52. Check the list of suppliers who offer discounts to SPA members. You may be able to save enough to cover one or more years subscription to the SPA....
Brian
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Re: GOTO in Theory and Practice

Post by Brian »

Tetenterre wrote:Inspired by a post in another thread:

Practice:
1. Initialise mount with n-star alignment.
2. --------

Steve omits to point out that carrying out "item 1" can take as long and be as frustrating as the actual GoTo steps needed to find the target - especially for "newbees" :shock: :lol:

ATB,
Brian
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Wellingborough UK.

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Tetenterre
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Re: GOTO in Theory and Practice

Post by Tetenterre »

Brian wrote:
Tetenterre wrote:Inspired by a post in another thread:

Practice:
1. Initialise mount with n-star alignment.
2. --------

Steve omits to point out that carrying out "item 1" can take as long and be as frustrating as the actual GoTo steps needed to find the target - especially for "newbees" :shock: :lol:
Ah. You missed #26! :D
Best,
Steve
The Binocular Sky
Astronomers do it with Heavenly Bodies

Lots of binoculars, from 32mm to 100mm; 90mm Gregory-Maksutov, 406mm Dob
Brian
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Re: GOTO in Theory and Practice

Post by Brian »

"Ah. You missed #26! "

Yes, you're right :oops: But only 30 minutes?.............. :lol:

ATB,
Brian
52.3N 0.6W
Wellingborough UK.

254mm LX90 on Superwedge, WO ZS66SD, Helios 102mm f5 on EQ1, Hunter 11x80, Pentax 10x50
ASI120MC Toucam Pros 740k/840k/900nc mono, Pentax K110D
Ro-Ro roof shed
Tetenterre
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Re: GOTO in Theory and Practice

Post by Tetenterre »

Brian wrote: But only 30 minutes?.............. :lol:
It was a good night when everything went smoothly first time. :lol:
Best,
Steve
The Binocular Sky
Astronomers do it with Heavenly Bodies

Lots of binoculars, from 32mm to 100mm; 90mm Gregory-Maksutov, 406mm Dob
M54
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Re: GOTO in Theory and Practice

Post by M54 »

The catch is that visit a club or go along to a public star party and more then 80% of the scopes are goto's of one make or another.

I visited a couple of event when Stargazing Live was around and literally nearly everything was a goto. Perhaps it is time to realise that they are the standard now, in which case if they were the "problem" implied they would not be.

Time to move on.
Tetenterre
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Re: GOTO in Theory and Practice

Post by Tetenterre »

M54 wrote:The catch is that visit a club or go along to a public star party and more then 80% of the scopes are goto's of one make or another.
Curious. Must be a different demographic where you live. I was at public SGLive events on Tuesday and Wednesday.

Tuesday: One out of 6 had GOTO. Biggest queue was at a '60s vintage 70mm refractor that was giving superb views of Jupiter and the Moon.

Wednesday: Zero out of 8 had GOTO.
Best,
Steve
The Binocular Sky
Astronomers do it with Heavenly Bodies

Lots of binoculars, from 32mm to 100mm; 90mm Gregory-Maksutov, 406mm Dob
mike a feist
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Re: GOTO in Theory and Practice

Post by mike a feist »

Maybe it is an "age" thing. Younger people brought up on computers are, I imagine, more likely to GOTO. Older long-time observers who who learnt the old way would either not need GOTO or find then to be an additional nuisance. I am finding more and more older observers giving up observing under cold dark conditions,and this may indeed increase the %age of GOTO in use. Alernatives that I have come across recently include observing through the window (me...esp crepuscular astronomy near west and east horizons), solar observing (obviously daytime), recording meteors using security-type cameras (and checking the results in the daytime) and even an observer who fitted large sheets of clingfilm across the slit of his observatory, and daytime location of Venus etc. Personally I only get out under dark midnight skies for "special" events like eclipses, occultations or comets when not accessible from the window. maf
brian livesey
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Re: GOTO in Theory and Practice

Post by brian livesey »

BAADER "Turbofilm" ( solar film without the coating ), mounted on a simple wooden frame, would be a good indoor observing alternative to a glass window, except perhaps in windy conditions.
Good quality cling film is almost as good as Turbofilm ( and far cheaper! ) and can give diffraction limited results.
brian
Eclipse
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Re: GOTO in Theory and Practice

Post by Eclipse »

David Frydman wrote: make the Earth flat,

Isn´t it ??
Coronado PST with SME-40 double stack H@ filter
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