iOptron CEM40 and saddle for side by side setup

[Juicy6]

Morning everyone!

The saddle on CEM40 has internal wiring for 12V and USB2. In order not to twist cables, there is a stop preventing it to turn more than one revolution. What is best way to attach my side-by-side setup scope? Am I supposed to unscrew saddle, turn it 90 degrees and tighten it or should I just define a new home position? Changing position of saddle will move mechanical stop to East or West I guess. Now it is at North, home,  position.

Christer, Sweden

[Buzzard75]

I wonder if it would be as easy as defining a new zero position. That tells the mount that your RA is straight up and down and your DEC is pointed toward the pole. It should (SHOULD) still know how far it can go in either direction before it hits the stops regardless of where that zero position is and move accordingly when moving to a target. I would try that before you tear it apart and try to adjust where the physical stops are. I would also recommend contacting iOptron before you attempt anything though.

The only other option may be to find a side by side saddle that has holes drilled in the crossbar dovetail that you can then mount to another dovetail.

[Rainer]

On 14/08/2019 at 00:21, Juicy6 said:

Morning everyone!

The saddle on CEM40 has internal wiring for 12V and USB2. In order not to twist cables, there is a stop preventing it to turn more than one revolution. What is best way to attach my side-by-side setup scope? Am I supposed to unscrew saddle, turn it 90 degrees and tighten it or should I just define a new home position? Changing position of saddle will move mechanical stop to East or West I guess. Now it is at North, home,  position.

Christer, Sweden

Hi,

Yes that is the solution to unscrew the saddle and rotate it 90 degrees. The stop touches the lower part of the dec head and not on the saddle.

The best is to unscrew the saddle and take a look where the stop is.

Rainer

Edited August 15, 2019 by Rainer

[Juicy6]

8 hours ago, Rainer said:

Yes that is the solution to unscrew the saddle and rotate it 90 degrees. The stop touches the lower part of the dec head and not on the saddle.

The best is to unscrew the saddle and take a look where the stop is.

Rainer

Great Rainer! I will try this out during weekend. Just unboxed the new CEM40 and this would be the simplest solution. Tech Service at TS in Germany where I bought it was not overly optimistic:

"this is good question. if you unscrew the saddle means you might modify the zero position. if you turn it 90° degrees it might not work. and if you don´t go for a dual saddle setup but for a classical one, telescope over telescope? The problem is the safety lock..I was having them in my past meade telescope and alway to be careful. also if you risk to to too close to the edge near the stop position, I don´t want you to risk to damage the mount. better to arrange the setup for me.."

I also asked iOptron Tech Support Team but no answer (yet).

Christer, Sweden

[Rainer]

11 hours ago, Juicy6 said:

"this is good question. if you unscrew the saddle means you might modify the zero position. if you turn it 90° degrees it might not work. and if you don´t go for a dual saddle setup but for a classical one, telescope over telescope? The problem is the safety lock..I was having them in my past meade telescope and alway to be careful. also if you risk to to too close to the edge near the stop position, I don´t want you to risk to damage the mount. better to arrange the setup for me.."

WOW 🤔

BTW you can not damage the ount as the steppers just make an awful grinding noise but nothing happens ... It is just not nice to hear them whining 🙂

I have two CEM 120EC2 mounts and have seen the CEM 60EC mount of a friend and they have this stops which act on the DEC head and not on the saddle.

Just tne sure to keep the DEC head pointing to the north and turn only the saddle by 90°, The footpreint of the 4 screws golding the saddle is square ...

My mounts have white arrows on the DEC head and those should point North. That is it. And so the Zero position is correct and you can slew to North and South about +-170°

 

Edited August 16, 2019 by Rainer

[Buzzard75]

I understand what you're saying now about removing the saddle. I misunderstood originally and thought you were talking about removing the DEC head and removing the stops. I'm still not convinced just removing it is going to accomplish what you're hoping it will. It appears the stop is just a set of two screws, one protruding up through the mount head and the other secured to the bottom of the saddle. I haven't checked to see if it is actually in the saddle or if there's something else under there. My guess is the saddle. Rotating it 90 degrees one way or the other is just going to move those two stops closer in one direction or the other. I think you're going to have to find a different solution.

Edited August 16, 2019 by Buzzard75

[Juicy6]

Just received answer from iOptron Tech Support:

"You have to remove the stopper and be careful not to over turning it. Yes, you need to remove and rotating the saddle 90 degree in order to make Zero Position Sensor works."

Christer, Sweden

[Rainer]

On 19/08/2019 at 02:53, Juicy6 said:

Just received answer from iOptron Tech Support:

"You have to remove the stopper and be careful not to over turning it. Yes, you need to remove and rotating the saddle 90 degree in order to make Zero Position Sensor works."

Christer, Sweden

This is an ambiguos answer. The CEM 40 has a built in search position sensor and so if you take out the stopper screw you can not use so you have to turn the saddle around for using the Zero Positio sensor.

Why do they give such stupid answers instead of just saying Turn the saddle by 90° ...

[Anne S]

I'm eventually going to do the same thing with my Cem60 once I've got used to it. I've asked Ian from Altairastro to show me how to do the Dec rotation when I'm at a Kelling Heath next month. I'll post details once I've seen how to do it. I'm worried about damaging the cables as I'll need to use the USB ports for the second telescope camera and filterwheel.

I imagine it'll be similar to your mount but I can ask him if there are any pitfalls if you like.

[Rainer]

1 hour ago, Anne S said:

I'm eventually going to do the same thing with my Cem60 once I've got used to it. I've asked Ian from Altairastro to show me how to do the Dec rotation when I'm at a Kelling Heath next month. I'll post details once I've seen how to do it. I'm worried about damaging the cables as I'll need to use the USB ports for the second telescope camera and filterwheel.

I imagine it'll be similar to your mount but I can ask him if there are any pitfalls if you like.

Hi,

There is absolutely no danger if you take off the saddle and turn it 90° or just ake it off for looking how it is set up.

The DEC head should have slots in order to accommodate the cables coming from the hollow DEC axis. As the mounts have the function Search zero position they have a built in sensor which reads the position of the DEC head and you can only have ONE Zero position.

The same was on my CEM 120EC2 mounts. Unscrew the 4 screws which hold the saddle plate and turn it 90 degrees and you have the double telescope set up possibility and you do not need to take off the stopper screw which acts on the DEC head and NOT on the saddle.

Again, I do not understand how iOptron does deliver such contradicting information being so easy to change it to a side by side arrangement.

[Rainer]

Hi,

Here it is how it works on a CEM 120EC2 or any CEM 120 model.

Look at the white arrow on the DEC Head which has to point North or South depending in which hemisphere you live. Very easy to find out just by unscrewing the saddle plate and looking underneath it.

Edited August 23, 2019 by Rainer

[Anne S]

1 hour ago, Rainer said:

Hi,

Here it is how it works on a CEM 120EC2 or any CEM 120 model.

Look at the white arrow on the DEC Head which has to point North or South depending in which hemisphere you live. Very easy to find out just by unscrewing the saddle plate and looking underneath it.

Thanks for posting those images. I see what you mean. One other thing, does it matter which way around you have the saddle?  I'd rather have the screws on the bottom, it'll be easier for me to tighten them. I've seen photos of them at the top.

[Juicy6]

12 hours ago, Rainer said:

Again, I do not understand how iOptron does deliver such contradicting information being so easy to change it to a side by side arrangement.

Me neither. After receiving this short strange reply i wrote the iOptron support back and suggested them to include this mod in the FAQ or Scope Manual:

"Thank you very much for reply. But I think I will wait with this until I have instructions with images to follow. I do not know if anything can go wrong. I think this should be described in the manual for your mounts. Here in Sweden there are many people using side-by-side setups for their gear.  The support at your German retailer Teleskop Service told me this mod is to be avoided. Also a few forum posters say this is not possible. Maybe presumtive buyers will choose another mount if it is not clearly stated that a side-by-side setup is possible."

This was 4 days ago. No reaction yet.  

Christer, Sweden

[Rainer]

12 hours ago, Juicy6 said:

Me neither. After receiving this short strange reply i wrote the iOptron support back and suggested them to include this mod in the FAQ or Scope Manual:

"Thank you very much for reply. But I think I will wait with this until I have instructions with images to follow. I do not know if anything can go wrong. I think this should be described in the manual for your mounts. Here in Sweden there are many people using side-by-side setups for their gear.  The support at your German retailer Teleskop Service told me this mod is to be avoided. Also a few forum posters say this is not possible. Maybe presumtive buyers will choose another mount if it is not clearly stated that a side-by-side setup is possible."

This was 4 days ago. No reaction yet.  

Christer, Sweden

Interesting how afraid people are to take off a simple saddle plate just because it has some cables attached to a Hub on the saddle.

I am even more astonished that iOptron themselves do not know how that works.

It does not matter where you want to put the tightening knobs of the saddle as well as it does not matter if you turn i Clockwise or Counterclockwise ...

I modified my whole DEC Head and Hub in order to get the cables from the hub symmetrically from inside both of my scopes.

 

 

[Juicy6]

12 hours ago, Rainer said:

Interesting how afraid people are to take off a simple saddle plate just because it has some cables attached to a Hub on the saddle.

I am even more astonished that iOptron themselves do not know how that works.

I am not afraid of modding things. I tried this and it is just a matter of turning the saddle where you want it. Very simple as you said. Nice work there on your own saddle setup, very nice! Agree with you about iOptron tech support AND their retailers.

Christer, Sweden

[Rainer]

8 hours ago, Juicy6 said:

I am not afraid of modding things. I tried this and it is just a matter of turning the saddle where you want it. Very simple as you said. Nice work there on your own saddle setup, very nice! Agree with you about iOptron tech support AND their retailers.

Christer, Sweden

Great, If you post an image of your set up now other people could see how it works 🙂

[UKAstroBill]

On this same issue I do not want to modify my CEM40 as I want to switch regularly between single  and dual operation. Is there a side by side kit that

(a) comes with a dovetail fitted to the cross bar at right angles, that dovetail pointing in the same direction as the two telescope mounts;

(b) the two mounts have brackets supporting both Losmandy and Vixen

(c) one side can be adapted to finder/guide shoe, preferably with directional adjustments?

Maybe I’m being lazy, but I just want to be able to swap between one and two with no fuss.

I’m pretty sure I could do it with ADM parts at huge cost, but what I’d like is an affordable complete kit that preserves all the orientations.

 

[conspicuity]

Interesting... and confusing.

My CEM40 arrived yesterday. As delivered the Dec head end-stop limits movement to roughly +/- 180deg either side of the centre position (indicated by the arrow on the saddle pointing up).

It makes no difference whether you adapt to side-by-side mounting by simply rotating the saddle 90deg or by unscrewing it and rotating it 90deg. The effect is the same; instead of +/-180deg you get 90deg one way and 270deg the other. This sounds potentially awkward when viewing objects below (or above, if you're in the southern hemisphere) the equator. 

Nothing is perfect, I guess. 

[Anne S]

I've a Cem60. I checked with Altair Astro. The fix is to remove the screw that prevents movement. You should unscrew the Dec saddle and rotate in 90 degrees. Just be careful of the internal wiring. I haven't done it yet as I'm still testing the telescopes that will be dual mounted. Just as well, I'm having an issue is the auto focuser bracket. It's moving sufficiently to upset autofocus.

Even my ieq30 pro had limited rotation but no wiring!

[conspicuity]

Thanks for that. I have just received a very quick response from iOptron with the same suggestion. I suppose it's obvious, but I have a reluctance to start removing bits less than 24 hours after delivery. Nevertheless, that's my next step.