Help please with Meade LX-90

[Nightjar]

I have a Meade 8" LX-90 classic ( no LNT) and I'm seeing something odd after alignment.

When I slew to Polaris or an object near the North Celestial Pole, the scope orientates itself upside down. It ends up pointing in the right direction, but the finderscope is now underneath and the eyepiece impossible to get to. Surely it can't be right ?

I'll tell you exactly what I'm doing in the hope that someone can spot what (if anything ) I'm doing wrong.

I set up the tripod with the wedge facing north, and level it .The Scope goes on, with the OTA parallel to the fork arms. Nudge the tripod until Polaris is in the FOV and adjust the wedge until it's centered.

Switch on, enter date, time, daylight savings = 'yes'. Check all settings :- Mount >Polar , Cord Wrap > On etc.

The I go through the '2 star' aligment procedure and get the 'alignment successful' message. Then when I GOTO any object it's in FOV.

Select Polaris then 'GOTO' and the scope slews itself into the awkward looking position I've described.

Any ideas anyone, or is this another of my scopes many quirks ?

Nightjar

[radioactive]

Is it possible that you have set the scope on the mount back to front at all ?

I don't know much at all about a wedge set-up but on an EQ mount it is possible to set the scope up 180% out of sync

Sorry that is all I can think of

[Nightjar]

I don't think there's a problem with the initial configuration - there's only one way up for the scope to fit on the wedge, and I've seen other SCT users set up in a similar way.

I'm thinking it must be one of the Autostar settings - but which ?

[Helen]

The scope can rotate 180 degrees on the base (ie the RA movement) while still being parallel to the fork arms. But if you've got it with the eyepiece facing up when you put the scope on the wedge I would have thought that would be OK. On the Celestron you have to start the alignment process with the scope at right angles to the forks and facing south, is there a similar thing for the LX?

Helen

[barkis]

With the scope facing North in the forks, both the OTA and the forks will be parallel. Loosen the declination knob, and raise the scope manually towards the zenith . It should only go so far passed, then stop, don't try to force it any further. The finder will be underneath.With the tube pointing North, and you standing behind it also looking North, the cable inputs on the mount should be on the right. Ron.

[barkis]

The home position in equatorial mode is pointing to the NCP, but that is for the LNT model, I don't know for the Classic. Have you selected polar mode in the Autostar menu?

[Nightjar]

Thanks for the replies so far everyone. Yes, I've got mount > polar selected. Sometimes my Autostar 'forgets' some of its settings, so I've got into a habit of checking them all during the alignment procedure. Another of its quirks.

Nightjar

[Paxo]

Nightjar,

I have a feeling that this is just one of the 'quirks' of the Meade fork mount. Having taken great care, and from what you have posted, you do the same, in setting up, when the mount slews to polaris, it turns to the correct RA and Dec (DEc should only be a fraction of a degree) then you adjust the wedge to centre polaris. I've ended up at some weird angles at times getting polaris in the viewfinder. You should be able to turn the diagonal though to a comfortable position once you polaris in the field of view.

Sorry I can't be more positive.

Steve..