9 replies to this topic

[qwernet]

I have a Meade LX600 12" with fork mount setup. There is already a short dovetail which is for the starlock:

 

 

Is it possible to add one more dovetail plate to the OTA so I can attach another small refractor that shares the guiding?

 

Or is it possible to replace the original short dovetail with a longer one? I can see 4 screws on the other end of the OTA:

 

 

I am not sure whether I can take the screws off and install another dovetail bar on it.

[carolinaskies]

Yes you can replace the shorty with a full accessory bar down the center length. 

ADM, Losmandy, etc offer complete bars for these SCTs. 

How you cobble together Starlock and whatever else is up to your ingenuity.  

You could do a side 'saddle' mount to the dovetail or offset seperate mounting on the accessory plate.   

There are several plates Losmandy offers you might want to accessory plate that comes pre-drilled with multiple attachment options of accessories.  

Be aware you'll need to likely counter balance any additional weight.  

Edited by carolinaskies, 02 December 2019 - 01:06 PM.

[qwernet]

Yes you can replace the shorty with a full accessory bar down the center length. 

ADM, Losmandy, etc offer complete bars for these SCTs. 

How you cobble together Starlock and whatever else is up to your ingenuity.  

You could do a side 'saddle' mount to the dovetail or offset seperate mounting on the accessory plate.   

There are several plates Losmandy offers you might want to accessory plate that comes pre-drilled with multiple attachment options of accessories.  

Be aware you'll need to likely counter balance any additional weight.  

 

Thanks! I just tried to take out the screws on the other side of the OTA (near the counter-weight rail). The hole spacing is 4 inches so it looks like it should fit the DM12 dovetail plate. I just ordered the ADM plate and rings. Hopefully it works.

 

Another question is: if I decide to go with side-by-side setup and re-attach starlock to a new saddle, is it necessary to keep starlock exactly parallel with 0 rotation to the main OTA? Assume that: 1. If starlock OTA points to an FOV which is several degrees off the main OTA's FOV; 2. The starlock OTA has like a ~10 degree rotation comparing to its original setup. Can starlock still get the correct RA/DEC direction on its sensor and perform the correct guiding / auto drift aligment?

[carolinaskies]

You'll want to keep Starlock parallel to the polar axis(ends up being the long axis of the tube of course), and of course you'll recalibrate.  Consider Starlock is also used on the LX850 and can be placed in various positions as long as it remains parallel. 

[qwernet]

You'll want to keep Starlock parallel to the polar axis(ends up being the long axis of the tube of course), and of course you'll recalibrate.  Consider Starlock is also used on the LX850 and can be placed in various positions as long as it remains parallel. 

Maybe LX600 is different. I just got a reply from Meade customer service saying that starlock cannot be hanging at an angle or sideways.

[carolinaskies]

I should have phrased that differently.  Starlock needs to be parallel to the OTA long axis only.  On intial alignment of course it would be aligned with the Polar axis, but as you move to new targets it stays parallel to the OTA axis... sorry for the confusion.  

[OzAndrewJ]

Gday Paul

IIRC, you cannot rotate it either

ie it "assumes" the cameras X axis is also parallel to the DEC axle ( in an LX600 )

Need to dig through my notes, but i think people who tried mounting it at different angles

came a cropper

Andrew Johansen Melbourne Australia

[carolinaskies]

Gday Paul

IIRC, you cannot rotate it either

ie it "assumes" the cameras X axis is also parallel to the DEC axle ( in an LX600 )

Need to dig through my notes, but i think people who tried mounting it at different angles

came a cropper

Andrew Johansen Melbourne Australia

I don't know why the LX600 would be any different from the LX850 software. 

[OzAndrewJ]

Gday Paul

For the StarLock, i dont think it is

AFAIK, The orientation of the sensor is "deemed" to be aligned with Alt and Az grid if AltAz

and RA/DEC grid if polar.

Simple to test, mount a Starlock with its base at 90deg to current and see if it works

 

Andrew Johansen Melbourne Australia

[qwernet]

Gday Paul

For the StarLock, i dont think it is

AFAIK, The orientation of the sensor is "deemed" to be aligned with Alt and Az grid if AltAz

and RA/DEC grid if polar.

Simple to test, mount a Starlock with its base at 90deg to current and see if it works

 

Andrew Johansen Melbourne Australia

If the firmware is smart enough, it should be able to test the DEC direction on sensor (e.g. during init, quickly move DEC forward / backward and check the trailing on sensor). But according to the reply from Meade customer service, they don't do this and always assume that sensor's X is DEC axle. I am wondering how precisely the sensor's X aligns with DEC axle. Starlock OTA is attached to main OTA only using a saddle. It looks parallelism can't be guaranteed, and there's no way to check and adjust. For guiding, I think a slight angle between sensor's X and DEC axle doesn't matter, as it is a negative feedback system. But for training / auto drift alignment, it seems this slight angle should be taken into account.