Mid longitude - where is it??

[ollypenrice]

Hi all,

I am mulling over the instructions for the Takahashi mount which should be arriving here in just over a week. In order to use the famed polar alignment scope I need to know the mid longitude of the Central European Time Zone (GMT plus 1Hr.) . Incrediblly enough I have so far failed to find out where it is on the net. Any ideas, anyone?

Olly

[Paxo]

Found this in Wikipedia Olly, it might be a starting point for you.

Central European Time - Wikipedia, the free encyclopedia

Steve

[Demonperformer]

Probably not very helpful, but this site: CET – Central European Time lists the countries that use CET. Maybe it really is as simple as taking the furthest point east and the furthest point west and splitting the difference.

No I'm not convinced either, but it's the best I can come up with.

[Demonperformer]

OK, Paxo posted while I was doing a search. I like his answer better, which would make it 15E (mid way between 7-30 and 22-30)

[ollypenrice]

Cheers gents. The trouble is that the time zone is not defined along lines of longitude for political and practical reasons but maybe the mid point bewtween the lines is still the way to go. All very confusing. Thanks.

Olly

[Tantalus]

Found this after a long search Olly, Dunno if it'll help though but maybe a clue... Astronomy: Astronomical mid-night, degree longitude, longitude latitude

[FraserClarke]

How does that alignment scope work? mid-longitude seems like a funny requirement; as you say, time zones are only roughly related to physical longitude. Surely you'd be most accurate using your actual longitude wouldn't you?

Just interested in how the alignment scope is meant to work really

[ollypenrice]

Thanks Tantalus, that's a great link. Very good of you.

Teadwarf, you do need your longitude and that goes into the mount's alignment data, yes. But your offset within the time zone needs to be plugged into the scale on the polar finder reticule. I guess they can't do this via your longitude because not all time zones are goegraphically consistent.

Olly

[MartinB]

Just use GMT Olly. The polar scope has a scaled adjustment which you set for your longitude (a one time job).

[davew]

Hi Olly,

Great instructions aren't they ??

A very nice chap, Hartmut Bornemann, has written a small application called Polar Finder. This works for the EM200. There is another one knocking about that does other Tak mounts. It comes in useful if you ever travel with the mount. ( No thinking ). Send me a PM with your email address and I'll try to send it out to you. That's if you want it.

Dave.

If you do I'll have to do it later. Going out right now.