Meade LX90 - How accurate are the ALT and AZ scales

[garethmob]

Just wondering if any one has used an LX 90 in the same way a wixey and base scale works on a dob?   if so how accurate is it?  

and how would i set it, do i need to zero everything on polaris or  0 x 0 pointing north?

Gareth

[Laurie61]

To use the setting circles you point the scope at a reference target star and then adjust setting circles to the appropriate position for that object, then you slew the scope to the desired location. In practice I would say the scale size on the lx scope is too small to do more than point the scope in the right general area. As the setting circles are not driven you need to perform the first stage to reset the setting circles at regular intervals.     

[ronin]

Meades are usually Level and pointing North so I presume that you zero in to that, although isn't zero in RA defined by pointing due South ??

So I would really expect 0,0 on the scales would be due South and level.

Equally the markers do not seem to be fixed or actually related to anything, the ones on the clutch rotate seperately to the tightening bit so almost any adjustment of the Dec clutch throws the zero position off. I have the impression they are there to make it look right and for appropriate decoration. Sometimes a circle of yellow ducks would be as much use.

On the ETX-70 there are no end stops, the thing will rotate infinitely so no real optimum initial position, as in equidistant between the end stops, as you are not going to run into an end stop ever.

[garethmob]

thanks both

as i use my power supply for the AT when imaging and the LX will only ever be for visual i thought if the setting circules could be used i could with help from the telrad get it all working and finding   with the ETX i know how "good" meade electronics are hence im not too worried about using manual mode