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Sigh, from a total amateur trying to learn / decode the language... for instance I found this on the web, I'm sure its correct (for its hemisphere or maybe both hemispheres) but I am trying to turn it into simple English and looking up basic astronomical terminology as you go (things like celestial equator, meridan, declination, illuminated reticle ocular) basic terms I have to learn and am now googling... to answer where I have marked ***
Declination Drift
This method of polar alignment allows you to get the most accurate alignment on the celestial pole and is required if you want to do long exposure deep-sky astro-photography through the telescope. The declination drift method requires that you monitor the drift of selected guide stars. The drift of each guide star tells you how far away the polar axis is pointing from the true celestial pole and in what direction.
* so far so good - sounds like what I need!
To perform the declination drift method you need to choose two bright stars. One should be near the eastern horizon and one due south near the meridian.
* * * Okay East I can see and near the horizon makes sense, one due South - but where is the meridan is that the South Celestial Pole - a picture would have been great!)
Both stars should be near the celestial equator (0° declination).
* * * Celestial equator - what is this term?
You will monitor the drift of each star one at a time and in declination only.
* * * What does in delination only mean?
While monitoring a star on the meridian, any misalignment in the east-west direction will be revealed.
* This makes some sense - a meridan (whatever this is shows East-west - my horizontal fine tuning controls)
While monitoring a star near the east/west horizon, any misalignment in the north-south direction will be revealed.
* * * North - South - is this my latitude setting?
As for hardware, you will need an illuminated reticle ocular to help you recognize any drift. For very close alignment, a Barlow lens is also recommended since it increases the magnification and reveals any drift faster.
* * * So is an illuminated reticle ocular an eye piece with markings to precisely show you how far from centre and in what direction (North, South, East, West) you are out?
When looking due south with the scope on the side of the mount, insert the diagonal so it points straight up.
* * * What diagonal - a 90 degree that inverst and flips the image or a 45 that doesn't?
Insert the cross hair ocular and align cross hairs to be parallel to declination and right ascension motion Use ±16x guide setting to check parallel alignment.
First choose your star near where the celestial equator and the meridian meet.
* * * In English please?
The star should be approximately ± 1/2 hour of the meridian and ±5° of the celestial equator. Center the star in the field of your telescope and monitor the drift in declination.
• If the star drifts south, the polar axis is too far east.
• If the star drifts north, the polar axis is too far west.
* * * Is this a Southern Hemisphere + 90 degree prism correction?
* * * I presume you are looking due East near the horizon not the SCP?, and looking only at the star's horizontal error to see if a star moves left towards North - so shift your mount West or right towards South - so shift your mount East - on your equatorial's horizontal East/West fine tuning?
Make the appropriate adjustments to the polar axis to eliminate any drift. One you have managed to eliminate all drift, move to the star near the east horizon. The star should be 20° above the horizon and ± 5° of the celestial equator.
* * * Opps is this the point East near the horizontal. Is that 20 degrees above the horizon and +/- 5 degrees of due East?
• If the star drifts south, the polar axis is too low
• If the star drifts north, the polar axis is too high.
* * * Again is this correct for the Southern hemisphere
Once again, make the appropriate adjustments to the polar axis to eliminate any drift. Unfortunately, the latter adjustments interact with adjustments ever so slightly. Therefore, repeat the process again to improve the accuracy checking both axes for minimal drift. Once the drift has been eliminated, the telescope is very accurately aligned. You will be able to do prime focus deep-sky astro-photography for long periods. NOTE: If the eastern horizon is blocked, you may choose a star near the western horizon however, you will have to reverse the polar high/low error directions. If using this method in the southern hemisphere, the procedure is the same as described above. However, the direction of drift is reversed.
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