Quote:
Originally Posted by barx1963
Loosening the base is something you do until you feel comfortable. If you loosen it too much it can swing around with any wind, so play around until it feels comfortable.
Manually moving a scope comes very easily after a while. The reversed image does take a little getting used to but after a while you just don't notice it any more. At high powers, you will find yourself moving the scope a bit. But if you think about it a standard 8" dob has a focal length of 1200mm. So a 10mm EP with a 50deg AFOV (apparent field) will give 1200/10 = 120x so 50deg/120 = 25' wide TFOV (true field) so an object moving through the sky at 15' per minute (which is how fast objects on the celestial equator move) will take 1.66 minutes to cross the field of the eyepiece. So you probably only give it a nudge every 20-30 seconds or so.
With a 25mm plossl, an object takes over 4 minutes to move across the field. I find the trick with high power is to work out which direction in the field the object is moving, and setup the view so the object moves through the centre of the field. That gives time for any vibrations in the scope to die down and for my eye to relax and start soaking in details.
Cheers
Malcolm
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Ok thanks, so If I am nudging it away or toward me, won't I have to move my seat and move away from the EP each time?
From the test set up I found my chair will not be high enough and I would be leaning slightly twisted to see into the EP,I was going to use a computer chair which if I put it on a pallett to gain height will probaly roll off.
Trying it down with straps, would be awkward if I decide to look in a new direction.
Guess I will have to experiment if the clouds ever go away!