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HELP! RA and Dec???


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;) Totally confused! Can someone help me please?

I've just got a 60mm x 900mm refractor scope on an EQ mount and I can't find a simple explanation of how the dials work and how you use them to find an object, I've got the polar axis set to about 54degrees, and I understand that you have to line in up with Polaris to start a night's viewing. I beleive this is so when you do find an object you only have to turn the slow RA control to keep an object in view. What I'm totally baffled by is to set up on Polaris my dials are at 90deg and 12hrs, is this right or have I got something the wrong way round, also it takes me ages to turn the 'scope upside down and round and round to get it pointing anywhere near what I want to look at without the 'scope hitting the slow controls or hitting the mount. (I tried to find Andromeda the other night and I couldn't get the 'scope pointing anywhere near upwards to see it!) I'm sure that someone on here will be able to explain to me in dummy terms how it all works and what I'm doing wrong. I can't figure out how RA and Dec work and whether or not it's affected by the time as the Earth rotates, feel really stupid asking this but I'm really new to this and probably thinking it's a lot more difficult than it actually is! This is a link to the nearest version of my 'scope

Telescope-Service: Refractors - Achromats, APOchromats, ED Refractors

It does have a motor with it but I haven't put it on yet as want to figure this all out first, I got the 'scope 2nd hand and it was already all put together. Any advice will be really appreciated:D

Matt

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With this size scope you do not need to be too accuarte in pointing at Polaris. The oly dial you nee worry about is on the side of the EQ mount labelled 0 to 90 which related to your latitude. Try this link for explanation.

Here is a link to a great website showing the correct way to move the scope once polar aligned.

Hope this helps

Mike

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DEC = "Latitude" in the sky and is measured in degrees, RA = "longitude" in the sky and is measured in time and 1 hour = 15 degrees.

If you are accurately polar aligned then to find an object you set the correct DEC angle then swing the scope to the correct RA and this is where the fun begins. The RA of an object is measured from the "first point of aries" fine but as the sky "rotates" around us that "hour angle" moves in the sky and you have to work out how to use the RA setting circle for it to be accurate to use.

So for example to make it easier you could find a bright object eg Vega, get it in the centre of your scopes FOV and having looked up the DEC and RA of Vega set your circles accordingly, then if you wish to find something else you can swing the scope about so the pointers are at the new objects DEC and RA.......but if your polar alignment is off, and it will be to some extent, finding the object you wish to view may not be so easy.

Another way is to star hop using a star atlas or something like stellarium a free program that is very useful.

Hope that helps

Pete

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