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1st Telescope (Celestron Powerseeker 127EQ) Help

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Hi I got this telescope as a Christmas present. Although its my first one I've been interested in astronomy for some time.

It has a German equatorial mount and my query is regarding the 'lock knobs' on all three of the axes. I was wondering whether it should still be possible to move the telescope about a certain axis after tightening its lock knob. The knobs do seem to make it slightly more difficult to move but I was thinking that perhaps they shouldn't move at all, negating excessive force. So I'm not entirely sure the mount is doing what it should be although at the same time its difficult to believe that all three knobs are malfunctioning?!

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I read the instruction manual for your scope and the three locking knobs are for the polar axis (once set the locking knob should keep the angle set without moving), and two for the RA and DEC slow motion controls. These two knobs should be tightened to offer some resistance to movement but still let the slow motion adjusters to operate? The only adjustment that should be locked (no movement) is the polar axis adjustment (adjusted to your latitude in degrees or using the North Star. The manual is not too clear on the use of the other two locking knobs/screws except maybe in setting the zero degrees DEC and zero hrs RA. Perhaps others that have this scope will pop in and maybe clarify the solution to your problem.

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The altitude lock knob should not allow movement at all. If you use the altitude adjuster screw in "push" mode to set your altitude, this tends to be quite stable, because the weight of the telescope is effectively pushing against the adjuster screw.

Theoretically the Polar (aka Right Ascension) Axis and Declination axis locking knobs should lock the axis but, with this mount in practice they usually don't quite manage. However, they are sufficiently tight to allow the slow-motion controls to adjust the scope. You should get into the habit of slightly slackening off the Dec and Polar locks when you are slewing your scope to a target (if it is balanced, it shouldn't slip), then tightening them and using the slow-mo knobs for fine adjustment. If you are polar aligned, you will need just the Polar slow-mo to track the object. However, precise polar alignment is tricky with this mount, so you will still need to use the Dec slow-mo to compensate for misalignment.

Not that the Dec Sow-mo has a limited amount of travel so, if you are compensating primarily in the same direction, you will eventually run out of adjustment. If this happens, unwind it to the middle of its range of travel, realign the scope, and start again.

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Thank you both for the friendly and informative replies and also Mr Q for going to trouble of reading the 127EQ manual! That has clarified things a lot. Yes basically, the polar axis is the most difficult to move and in any case will return to exactly the same place (unless you actually adjust it the proper way of course). The Dec axis actually locks fairly well but not completely. The RA axis moves the easiest when 'locked' but it does still allow for movements about the other axes alone whilst maintaining its place reasonably well.

So it seems to be working properly which I'm glad of, will definitely be taking it out very soon and will no doubt be posting here again sometime!

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I'd be interested in hearing how this telescope works for you. I was just looking at it on amazon. My wife has a little trouble lugging the Z10 out for a view so I'm looking for something more portable for her to use when I'm not available to set up the "big" scope. At any rate it looks like a great first scope and the price is pretty attractive as well. Happy New Year and clear skies to you...



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